10 International Conference on Urban Drainage

Transcription

10th International Conference on Urban
Drainage
Copenhagen, Denmark, August 21-26, 2005
Organised by:
Institute of Environment & Resources
Technical University of Denmark
Section of Environmental Engineering
Aalborg University
Edited by:
Eva Eriksson
Hülya Genç-Fuhrman
Jes Vollertsen
Anna Ledin
Thorkild Hvitved-Jacobsen
Peter Steen Mikkelsen
Abstract collection
Eriksson E., Genç-Fuhrman H., Vollertsen J., Ledin A., Hvitved-Jacobsen T. and Mikkelsen P.S. (Eds.)
(2005): 10th International Conference on Urban Drainage 21-26 August 2005, Copenhagen/Denmark,
Abstract collection, 68pp.
Published by:
Bygningstorvet, Building 115
DK-2800 Kgs. Lyngby
Phone: +45 4525 1610
Fax: +45 4593 2850
E-mail: [email protected]
http://www.er.dtu.dk/English/Publications.aspx
here you will find a search function in which you
can search for this Abstract collection
ISBN 87-89220-80-3
The copyright for any individual abstract rests with its author(s).
2
10th International Conference on Urban Drainage – Abstract collection
List of contents
Foreword
4
Acknowledgements
5
Abstracts - based on first authors last name
7
Abdallah
7
Ball
10
Caletkova
16
Davies
20
Egarr
22
Fach
23
García-Sala
24
Hamioud
28
Ishikawa
31
Jacobs
31
Kabelkova
32
Lamarre
36
Ma
38
Nakajima
44
O'Brien
45
Paoletti
46
Quiblier
49
Ráduly
49
Sakakibara
53
Tafuri
59
Uetsuka
62
Vaes
62
Wada
64
Xu
66
Zaizen
66
3
Foreword
The triennial International Conferences on Urban Drainage (ICUD) have long been recognized as highly prestigious events serving to
disseminate significant research results to the international urban drainage community. The 10th ICUD continues a tradition begun in
Southampton, 1978, and many parts of the world have hosted the conference since then:
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1978
1981
1984
1987
1990
1993
1996
1999
2002
2005
Southampton, United Kingdom
Champaign-Urbana, Illinois, United States of America
Gothenburg, Sweden
Lausanne, Switzerland
Osaka, Japan
Niagara Falls, Ontario, Canada
Hannover, Germany
Sydney, Australia
Portland, Oregon, United States of America
Copenhagen, Denmark
The 10th International Conference on Urban Drainage (10ICUD) held in Copenhagen, Denmark during 21-26 August 2005 is organised
by:
Institute of Environment & Resources,
Technical University of Denmark, and
Section of Environmental Engineering,
Aalborg University, Denmark
The Executive Committee for the conference consists of faculty members from the two organising universities:
•
Thorkild Hvitved-Jacobsen, Aalborg University
•
Anna Ledin, Technical University of Denmark
•
Peter Steen Mikkelsen, Technical University of Denmark (Chairman)
•
Jes Vollertsen, Aalborg University
The conferences are organised under the auspices of the IWA/IAHR Joint Committee on Urban Drainage, typically in collaborate with
other national or international associations. The 10th ICUD is organised in collaboration with:
Joint Committee on Urban Drainage (JCUD) of the International Water Association (IWA) and the
International Association of Hydraulic Engineering and Research (IAHR)
The Urban Water Resources Research Council (UWRRC) of the Environmental & Water Resources
Institute (EWRI) of the American Society of Civil Engineers (ASCE)
Danish Water Pollution Committee (DWPC) and The Society for Environmental Engineering
(IDAmiljø) - The Society of Danish Engineers (IDA)
Danish Water and Waste Water Association (DANVA)
The focus of the conferences was from the outset to combine hydraulics and water quality research to solve practical problems.
However, the past years have seen the conference subject undergo significant changes; both towards increased detail in process
understanding and towards understanding integrated aspects related to natural and technical sciences as well as social and
environmental issues and management.
The programme of the 10th ICUD is divided in 13 comprehensive themes:
Theme A
Theme B
Theme C
Theme D
Theme E
Theme F
Theme G
Theme H
Theme I
Theme J
Theme K
Theme L
Theme M
4
Data and models
Urban rainfall and hydrology
Urban drainage hydraulics
Receiving water impacts
Management and planning
Sewer processes and networks
Technology for CSO and stormwater treatment
Ponds, wetlands, infiltration basins
Small scale stormwater systems
Pollutant sources and transport
Urban water and society
CityNet, the network of European research projects on integrated urban water management
Miscellaneous, including Education and training and Special conditions in cold climate
The 10th ICUD also introduces the Poul Harremoës Award for Best Urban Drainage Paper by a Young Author. Vision and innovation
were the hallmarks of Prof. Poul Harremoës’ (1934 - 2003) career. In recognition of his contributions to advancing knowledge in
environmental sciences and engineering related to urban drainage, the Joint Committee on Urban Drainage, in cooperation with the
International Water Association, has established a triennial competition for the best paper written by a young author to be held in
conjunction with the Committee’s conferences on urban drainage. The award will be given for the presentation of novel and ideally,
provocative, ideas relating to developments in urban drainage.
The Abstract collection contains 376 short abstracts accepted for presentation at the conference and for which full preprints (drafts)
are available on the conference CD. The papers are organised on alphabetical listing of the primary author’s surname. The
conference programme is not included here but can be viewed on the conference website at http://10icud.er.dtu.dk, where a
comprehensive search facility is also available. The conference website also contains general information about the conference.
The accepted papers have been selected based on a two-stage peer review process. Abstracts were submitted in response to the first
and second Call for Abstracts during summer and autumn of 2004. These were reviewed and authors were requested to submit full
papers by 1 February 2005, taking into account the feedback that was provided from the review process. The submitted full papers
were reviewed and notification on paper (conditional) acceptance was given in April 2005. Notification of session type (platform
session, workshop or poster session) was given on 1 June 2005, and authors were allowed to resubmit revised versions of the
conditionally acceptance manuscripts during June 2005 to accommodate the criticism raised by the reviewers. The papers were
finally reviewed by the Executive Committee and edited during July 2005 before the Abstract collection and the CD was produced.
It is our hope that conference attendants will find this Abstract collection a useful resource during and after the conference, and we
encourage all authors to collaborate with us towards the common goal of publishing the content of the CD after the conference.
Kgs. Lyngby, August 2005
Peter Steen Mikkelsen
Chairman of the 10ICUD Executive Committee
Acknowledgements
An international scientific committee, consisting of members of the IWA/IAHR Joint Committee on Urban Drainage as well as other
international urban drainage experts has helped by advising the Executive Committee on scientific matters (suggesting reviewers,
main conference themes, and scientific programme) and by spreading the word about this conference around the world. The 10ICUD
Advisory Scientific Committee consists of:
Karsten Arnbjerg-Nielsen, Denmark
Richard Ashley, United Kingdom
Jean-Luc Bertrand-Krajewski, France
David Butler, United Kingdom
Thomas Einfalt, Germany
Govert Geldof, The Netherlands
Kapil Gupta, India
Peter Krebs, Germany
Joseph Hun-Wei Lee, Hong Kong
Per-Arne Malmqvist, Sweden
Ole Mark, Denmark
Jiri Marsalek, Canada
Rafaela de Saldanha Matos, Portugal
Jean-Marie Mouchel, France
Nilo Nascimento, Brazil
Van-Thanh-Van Nguyen, Canada
Jaroslav Pollert, Czech Republic
Wolfgang Rauch, Austria
John Sansalone, USA
Wolfgang Schilling, Norway
David Stephenson, Botswana
Eric Strecker, USA
Sveinung Sægrov, Norway
Maria Viklander, Sweden
Tony H. F. Wong, Australia
Mitsuyoshi Zaizen, Japan
To increase the quality of the detailed programme planning a number of reputable experts were involved in planning the programme
within each of the 13 defined themes (see the Foreword) and suggesting chairpersons for the sessions. Apart from members of the
Executive Committee these were: Thomas Einfalt (G), Govert Geldof (NL), Wolfgang Rauch (A), Gilles Rivard (CA), John Sansalone
(USA), Manfred Schuetze (G), Tony Wong (AU) and Mitsuyoshi Zaizen (JP).
Furthermore, the reviewers are acknowledged for their efforts in peer reviewing first the abstracts and later the papers submitted
for the conference. The comprehensive feedback to authors, which enabled them to improve their papers and submit revised
versions, is greatly appreciated. The reviewers are:
Suhaimi Abdul-Talib, Malaysia
Barry J. Adams, Canada
Stefan Ahlman, Sweden
Mathieu Ahyerre, France
Nadine Aires, France
Maria do Céu Almeida, Portugal
Karsten Arnbjerg-Nielsen, Denmark
Richard Ashley, United Kingdom
Linda Bagge, Denmark
James Ball, Australia
David Balmforth, United Kingdom
Ana Barbosa, Portugal
Jean Pascal Bardin, France
Sylvie Barraud, France
Krist V. Gernaey, Sweden
Joel Goldenfum. Brazil
Oliver Gretzschel, Germany
Guenter Gruber, AustriaS
Morten Grum, Denmark
Kapil Gupta, India
Asbjørn Haaning Nielsen, Denmark
David Hansen, Canada
Belinda Hatt. Australia
Mikkel Boye Hauger, Denmark
Mogens Henze, Denmark
Roumiana Hranova, Botswana
Bo N. Jacobsen, Denmark
Ketah Jansons, Australia
Botond Ráduly, Italy
Georges Raimbault, France
Wolfgang Rauch, Austria
Karin Reinosdotter, Sweden
Mike Revitt, United Kingdom
Jörg Rieckermann, Switzerland
Erik Ristenpart, Germany
Gilles Rivard, Canada
Larry Roesner, USA
Christine Rohrer, USA
Mandy Rutsch, Germany
Sveinung Sægrov, Norway
John Sansalone, USA
Kjeld Schaarup-Jensen, Denmark
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Christian Beck, France
Ton Beenen, The Netherlands
Jean-Luc Bertrand-Krajewski, France
David Blackwood, United Kingdom
Pawel Blaszczyk, Poland
Marco Borga, Italy
Hansjoerg Brombach, Germany
Rebekah Brown, Australia
Bilgin Buberoglu, Canada
Stewart Burn, Australia
David Butler, United Kingdom
Alberto Campisano, Italy
Adriana Cardoso, Portugal
Adrian Cashman, United Kingdom
Matthieu Chabanel, France
Bernard Chocat, France
Jens Hesselbjerg Christensen, Denmark
Francois Clemens, The Netherlands
Ian Clifforde, United Kingdom
Hubert Colas, Canada
Bob Crabtree, United Kingdom
Aidan Cronin, United Kingdom
John Davies, United Kingdom
Ana Deletic, Australia
Jean-Claude Deutsch, France
Francesco di Pierro, United Kingdom
Carsten Dierkes, Germany
Slobodan Djordjevic, United Kingdom
Thomas Einfalt, Germany
John Bryan Ellis, United Kingdom
Volker Erbe, Germany
Eva Eriksson, Denmark
Thomas Ertl, Austria
Dominique Faure, France
Dick Fenner, United Kingdom
Cathelijne Flamink, The Netherlands
Tim Fletcher, Australia
Lothar Fuchs, Germany
Shoichi Fujita, Japan
Johnny Gasperi, France
Jozsef Gayer, Hungary
Govert Geldof, The Netherlands
Hülya Genç-Fuhrman, Denmark
Jonas German, Sweden
Chris Jefferies, United Kingdom
Niels Aagaard Jensen, Denmark
Mogens Jensen, Denmark
Claude Joannis, France
Ian Joliffe, Australia
Jim Joyce, USA
Louis Julien, Canada
Jesper Kjølholt, Denmark
Hans Korving, The Netherlands
Peter Krebs, Germany
Ralf Kutzner, Germany
Jean Lacoursière, Sweden
Thomas Larm, Sweden
Frédérique Larrarte, France
Torben Larsen, Denmark
Yves Le Gat, France
Pascal Le Gauffre, France
Anna Ledin, Denmark
James Li, Canada
Hong Lin, USA
Erik Lindblom, Denmark
Dinfang Liu, USA
Christof Lubbers, The Netherlands
Christos Makropoulos, United Kingdom
Ole Mark, Denmark
Jiri Marsalek, Canada
Rafaela Matos, Portugal
José Manuel de Saldanha Matos, Portugal
Peter Steen Mikkelsen, Denmark
Jean-Marie Mouchel, France
Mauro Naghettini, Brazil
Alan Newman, United Kingdom
Phillimon Odirile, Botswana
Gary Oberts, USA
Christoph Ort, Switzerland
Manfred Ostrowski, Germany
Brett Phillips, Australia
William C. Pisano, USA
Robert Pitt, USA
Jaroslav Pollert, Czech Republic
Mônica Porto, Brazil
Chris Pratt, United Kingdom
Antoine Proton, France
Markus Quirmbach, Germany
Willi Schmid, Switzerland
Theo Schmitt, Germany
Manfred Schuetze, Germany
Will Shepherd, United Kingdom
Michael Munk Sørensen, Denmark
Sonia Sørensen, Denmark
Markus Starkl, Austria
David Stephenson, Botswana
Eric Strecker, USA
Gilbert Svensson, Sweden
Jean-Pierre Tabuchi, France
Simon Tait, United Kingdom
Naoya Tanaka, Japan
Bruno Tassin, France
Andre Taylor, Australia
Zheng Teng, USA
Daniel Thevenot, France
veinn T. Thorolfsson, Norway
Jean Philippe Torterotot, France
Mathias Uhl, Germany
Ben Urbonas, USA
Guido Vaes, Belgium
Esther van Beurden, The Netherlands
Bert van Duin, Canada
Peter Vanrolleghem, Belgium
Maria Viklander, Sweden
Jes Vollertsen, Denmark
Eduardo von Sperling, Brazil
Ed Watt, Canada
Sutat Weesakul. Thailand
Patrick Willems, Belgium
Will Williams, United Kingdom
Paul Wisner, Canada
Leif Wolf, Germany
Tony Wong, Australia
Ada Wossink, USA
Mitsuyoshi Zaizen, Japan
Evzen Zeman, Switzerland
Ping Zhou, USA
Ullrich Zimmerman, Germany
Mathieu Zug, France
George Zukovs, Canada
The Executive Committee is grateful to the capable conference secretary, Mia Clausen of MIACON Meeting and Conference Services,
whose persistent work made the practical arrangement successful, to the web-developer, Erik Nørby from PolyTec, whose
experience and skills helped to design and create a conference management system that helped to ease both the registration process
and the handling of papers. Birte Brejl from Institute of Environment & Resources at DTU is thanked for creating the graphics used in
the conference logo, and to Hugo Connery from the eCentre at the same institute is thanked for compiling the data for the
conference CD.
Finally, the Executive Committee wishes to acknowledge the effort of Eva Eriksson and Hülya Genç-Fuhrman, Institute of
Environment and Resources, Technical University of Denmark. Creating this Abstract collection and the conference CD with draft
papers (preprints) would not have been possible without their tireless quality controlling and editing of papers.
6
Abstracts
Combining and dividing flow through junction. M. Abdallah*+; R. Mose; J. Vazquez; M. Zoaeter
Presented by Maher Abdallah, Ecole nationale du génie de l´eau et de l´environn, France
The objective of the present work is to find numerically the water level and water discharge of the flow in a network of channels
containing junctions. A one-dimensional model is considered and completely described allowing a full comprehension of the modeling
of water flow through junction. In channels, the mathematical model used is the shallow water equations, the so-called Saint Venant
equations, while for junction, different models of equations based on momentum or energy conservation exist. In this paper, we
consider the explicit scheme of Roe to solve the Saint Venant equations, and four available models for combining junction and four
others for dividing junction to solve the water level at junction. The method of characteristics is used to couple the solution in
channel with that of junction. The comparison of the various junction models shows that the model of equality of water stages
provides results very different in term of water depth and discharge. The conclusion drawn from this paper is that, the use of the
equality of water stages model largely used in the classical hydraulic engineering codes is worrying and should be replaced by a
model based on momentum conservation.
Increase of river base flow by hydropower gate operation for mitigation of CSO impacts - potential and limitations. S.
Achleitner*+; W. Rauch
Presented by Stefan Achleitner, University of Innsbruck, Austria
Impacts of CSO spilling during storm weather is of special concern within small river or man made low flow stretches (e.g. caused by
hydropower operation). For the latter, this measure aims to increased the base flow temporal in order to mitigate negative (acute)
impacts from the CSO onto the river eco system. Goal is to provide sufficient dilution by operating upstream located retaining
structures such as hydropower intakes. Both - energy producers and municipalities - are required to cooperate. Thus, the measure
fits into a core aim of the Water Framework Directive of having basin wide approaches for improvements of ambient water quality.
The measure focuses on the mitigation of acute pollutants (here ammonia and copper) only, while mitigation of delayed or
accumulative impacts is not intended. A model based predictive control, utilizing rain forecast, was chosen for real time control
(RTC) of the hydropower operation. Uncertainties in the rain forecast are discussed and a specially developed operational algorithm
is presented and tested off-line with different semi-virtual catchments. The different scenarios were evaluated for possible
ecological limitations of the measure and the associated costs. In contrast, increased CSO volumes were found to be an inappropriate
alternative, leading to unrealistic high volumes and consequently costs.
CITY DRAIN © - A simulation software for integrated modeling of urban drainage systems. S. Achleitner*+; W. Rauch
Presented by Stefan Achleitner, University of Innsbruck, Austria
Over the last years design procedures of urban drainage systems are subject to a shift from end of pipe design criteria to ambient
water quality approaches. Emphasis is nowadays put on the improvement of the receiving water quality by an overall management of
river basins, which is a core element of the water framework directive (WFD) as well. For the application in practice software tools
are required that are capable of modelling urban drainage systems (including the receiving water) in an integrated way having
rainfall as the elementary input. For use in the daily engineering work such software tools are required to be simple in handling and
to provide a certain flexibility to be adjustable for different scenarios. CITY DRAIN is developed in a Matlab/Simulink © environment
for simulation of urban drainage systems. The different parts of an urban drainage system (catchment, sewer system, storage
devises, receiving water) are built in blocks representing dynamic subsystems with different underlying modelling approaches for
hydraulics and mass transport. These blocks can be freely arranged and connected to each other in order to describe an integrated
urban drainage system and the fluxes of water and matter. The underlying models in CITY DRAIN are kept simple on purpose, using
fixed discrete time steps for dynamic simulation. Still, the open structure of the software allows to add own blocks and/or modify
blocks, being necessary to model specific aspects or processes.
Experimental study of permeable reservoir pavements for surface runoff control at source. L. A. Acioli; A. L. L. da Silveira; J. A.
Goldenfum*+
Presented by Joel Goldenfum, IPH-UFRGS, Brazil
The uncontrolled expansion of the majority of the cities is generating many infrastructure problems and environmental impacts. The
usual drainage systems have proved to be inefficient and excessively expensive. Alternative solutions, trying to compensate
urbanisation and imperviousness effects are being researched, trying to favour source control. This paper presents an experimental
study, developed at IPH-UFRGS (Institute for Hydraulic Research of the Federal University of Rio Grande do Sul), in Porto Alegre,
Brazil, which seeks to monitor and analyse the behaviour of pervious pavements, when subjected to usual traffic conditions. A
parking lot of 280 m2 was built, allowing intensive and continuous monitoring of two different types of pervious pavements: (i)
asphalt; (ii) concrete garden blocks, filled with grass. Water quantity and quality data are collected in order to evaluate the
performance of permeable pavements and to appraise its feasibility in specific soil and weather conditions of the city of Porto
Alegre/Brazil. The preliminary results show a good performance of the permeable pavements: low values were observed both for
runoff and maximum storage in the reservoirs. Low infiltration rates were also observed, as consequence of the clay soil, as
expected from the previous soil characterisation tests, performed before the site construction.
A modelling tool for simulation of sources and fluxes in wastewater systems: Focus on stormwater source control. S. Ahlman*+;
H. Sieker; G. Svensson
Presented by Stefan Ahlman, Chalmers University of Technology, Sweden
A modelling tool called STORM/SEWSYS has been proposed that makes it possible to simulate different scenarios of stormwater
source control practices. Source control is an important method to reduce runoff volumes and peak flows, and at the same time
improving the stormwater quality. The modelling concepts of two previously developed models, STORM and SEWSYS, have been
combined and integrated to make it possible to use the new tool to simulate different stormwater source control practices. Various
structural measures such as detention and re-use, swales and soakaways, catch-basins, wetlands, ponds, porous paving, and nonstructural methods like public regulations or street sweeping are source control techniques that have been incorporated in the
modelling framework of the tool. The STORM/SEWSYS model provides simulation techniques to evaluate changes to the hydrological
cycle and hydrological risks in urban catchments. A detailed pollutant transport module where pollutants from different activities in
the urban area are separated in their respective origin; material corrosion, brake wear, tyre wear etc. is included in the model and
facilitates quality source control. This paper describes the new integrated sources and flux model STORM/SEWSYS and discusses the
new possibilities the modelling approach will bring forward.
7
Full scale testing of enhanced local treatment of CSOs enabling a cost-efficient implementation of the EU Water Framework
Directive. N.K. Andersen; P. Hallager; A. Laustsen, J.B. Nielsen; N.T.D Kristensen; P. Nordemann; W. Rauch; G.G. Nielsen; K.
Arnbjerg-Nielsen*+
Presented by Karsten Arnbjerg-Nielsen, COWI, Denmark
There is a definite need for full-scale applications on which to judge the efficiency of novel processes for local treatment of
combined sewer overflows (CSO). Three full-scale facilities are constructed to study typical types of CSO discharges: 1) Discharges
from small upstream catchments to small watercourses, 2) Discharges from larger catchments to larger surface water, and 3)
Discharges to marine coastal waters where bathing is permitted. The paper outlines the proposed technologies and discusses the
preliminary results of an on-going measurement program. The treatment efficiencies of the technologies are tested with equal focus
on both chemical and biological parameters because CSOs are also a human health issue.
Construction and testing of a CSO treating combined sewage to bathing water quality standards. N. K. Andersen*; C. Cronqvist; P.
Nielsen+; L. L. Mathiasen; A. Albrechtsen; L. Bentsen
Presented by Niels Kofod Andersen, Copenhagen Energy, Denmark
Traditional design of combined sewer overflows is known to have detrimental effects sometimes preventing surface waters from
having a good status. Implementation of the Water Framework Directive highlights the need to bridge the gab between discharge
permits and resulting water quality in surface waters from combined sewer discharges. New concepts must be developed and tested
in full scale. The poster discusses the design, construction and testing of a treatment plant specifically intended for combined
sewage. The outlet event mean concentrations are expected to be less than 500 E. coli /100 ml and less than 30 mg suspended
solids/l. The treatment plant consists of three steps of physical removal of solids as well as UV radiation. Each step has been tested
individually, but the processes have not been combined and tested in full scale with large variations in the load which is an inherent
feature when treating combined sewage. The plant will be ready for the bathing season of 2005. The performance of the plant will
be monitored closely throughout the bathing season as well as the improvement of the water quality in the surface water. The
results will be presented on the poster as well as on a technical tour.
Highway runoff characteristics in coastal areas – A case study in Aveiro, Portugal. P. A. Antunes*+; A. E. Barbosa
Presented by Pedro Antunes, Escola Superior de Tecnologia de Viseu, Portugal
In the framework of a study for the Portuguese Road Institute, the authors carried out a monitoring study of the IP5 highway, located
at the coast line. The TSS and the turbidity values measured in 40 runoff samples were relatively low, resulting from the low
potential of the drainage area and surroundings to contribute with solids. Heavy metals results (Fe, Zn, Cu, Pb, Cd and Ni) were in
accordance with other studies. It was confirmed the continuous decrease in Pb concentrations in stormwater. Analysis revealed high
levels of salinity (161 mg/l) and chlorides (51.3 mg/l) that are usually reported only for roads with de-icing salts application.
Searches in the literature revealed only one reference to marine aerosols as contributing to chloride presence in stormwater, and no
notice of increased pavement deterioration in coastal highways. Salinity present in coastal areas may provoke structural alterations
in the pavement that may be associated to a larger release of its constituents. The fact that black particles were observed both in
the runoff samples and at the IP5 drainage system may be indicators of such phenomena. The authors plan to carry on further field
and laboratory investigations, with the objective of better understanding these phenomena.
The social impacts of stormwater management techniques. S. Apostolaki+; C. Jefferies*; T. Wild
Presented by Stella Apostolaki, University of Abertay Dundee, United Kingdom (Great Britain)
This paper presents the results of research into the social impacts of stormwater management techniques applied within urban
environments. The main aim of the study was to compare public and professional attitudes of stormwater management practices
such as Sustainable Urban Drainage Systems (SUDS) and river management techniques. Any new and innovative technology used in
residential areas, besides being economically and environmentally acceptable, must also be accepted by the residents. There has
been considerable interest in the assessment of the public perception of SUDS in the UK by consultants, developers, the Environment
Agency of England and Wales as well as by the Scottish Environment Protection Agency (SEPA). This research was undertaken to
inform such interest and also to obtain a more holistic view of the perception by professionals of SUDS. A comparative study of the
perceptions of river management in three densely populated European cities facing similar storm water management problems was
carried out. The selected cities were Glasgow in Scotland – U. K., an area in west London, England - U.K., and part of Athens –
Greece. All sites were located within flood-prone suburban areas, and different river management techniques have been proposed or
adopted.
Occurrence and relative abundance of mosquitoes in stormwater retention facilities in North Carolina, USA. C.S. Apperson; W.
F. Hunt III*+; S. Kennedy; B.A. Harrison; W.G. Lord
Presented by William Hunt, North Carolina State University, United States of America
Throughout the 2004 mosquito season, 52 stormwater retention facilities were sampled to characterize the seasonal occurrence and
relative abundance of mosquito species in relation to the structural complexity and biological diversity of the facilities. The three
different types of facilities included standard wet ponds (n = 20), innovative ponds (n = 14), and wetland ponds (n = 18). All
retention structures were sampled at the beginning, middle and end of the mosquito season so that seasonal changes in mosquito
production could be characterized. Overall samplings, mosquitoes were collected from 34% of the retention structures. Fourteen
species representing 7 genera were collected, but only 5 species (Culex erraticus, Cx. territans, Anopheles quadrimaculatus, An.
punctipennis and Uranotaenia sapphirina) were commonly collected in all three types of stormwater management facilities. In
general, the seasonal prevalence and relative abundance of mosquito species did not vary among three types of retention structures.
A significant association (P < 0.01) between the presence of mosquito larvae or pupae and the absence of mosquitofish was found for
innovative and wetland stormwater retention facilities but not for standard retention facilities (P > 0.05).
Head loss at three-way circular drop manhole and its reduction by improvement in base shape. S. Arao*+; T. Kusuda
Presented by Shinji Arao, CTI Engineering Co., Ltd., Japan
In this study, firstly, head loss at a three-way circular manhole with drops among the main upstream pipe, the lateral pipe, and the
downstream pipe was examined. Experimental results indicate that the head loss due to the level difference between the lateral and
downstream pipes in a three-way circular drop manhole is rather small under surcharge flow. Secondly, reduction in head loss at a
three-way circular manhole with several new manhole bases was studied under surcharge flow. The head loss at the manhole with a
flat cover plate above full benching fairly decreases as the ratio of flow rates in the lateral and upstream pipes increases under
surcharge flow. Finally, a new formula for energy loss coefficient was proposed which is a function of structural and hydraulic
elements, such as manhole size, pipe size, drop between upstream and downstream pipes, connecting angle of the pipes, and water
depth in the manhole. The calculated energy loss at a two-way circular drop manhole by the proposed new formula falls within an
error of ±30% of the measured ones except for some structural conditions on manhole and connecting pipes.
8
Significant climate change of extreme rainfall in Denmark. K. Arnbjerg-Nielsen*+
During the last years practitioners of urban drainage has complained that they felt that surcharging occurred more frequently.
Therefore a study was initiated focussing on the variations in extreme rainfall during the last two decades. In Denmark a total of 41
rain gauges with a high resolution in time and volume have an observation period close to 20 years. The rainfall observed at these
gauges was selected for this study. Three variables were analyzed for statistically significant trends during the observation period:
Maximum average 10 minute intensity, maximum average 6 hour intensity and the total volume of individual rain events. For the 10
minute maximum intensity there is a statistically significant trend towards more extreme and more frequently occurring rain storm.
The trend is pronounced in the eastern part of the country and below statistically significant levels in the western part of the
country. For the 6 hour maximum intensity and total volume of events the trends are less pronounced. The findings are confirmed by
comparison to physically based climate models and studies based on large regions.
How to divide hydrographs into the original sources of runoff. K. Arnbjerg-Nielsen+; A. B. Hasling; N.B. Johansen; C. R. Petersen;
H. S. Andersen; M. Grum; F. Agerskov; J. Thyme; S. Nielsen; T. H. Nielsen; H. M. Petersen; J. Nørremark; B. N. Jacobsen*
Today, many sewer systems are monitored closely with on-line data with high resolution in time. This information is used to plan and
optimize the management of the system by checking pump performance, counting the number and size of combined sewer overflows
etcetera. Sometimes the data is also used to calibrate hydrodynamic models of the sewer system. However, the information can also
be used to study long-term changes in the performance of the sewer system and to identify sources of water not belonging to the
sewer system. The paper discusses what types of runoff can be assessed based on different types of measurements, ranging from
pumping stations with daily readings of pumping time to several years of accurate flow measurements distributed throughout the
sewer system. The sources are divided into four identifiable sources: sewage, slow infiltration, paved runoff, and fast infiltration.
The objective is to identify these sources based on time series of one flow gauge and on rain information. The pros and cons of four
approaches are discussed and the methods are applied to a case study. With care, the simple spreadsheet calculation approach
yields similar results as the more comprehensive methods. However, the result is to some extend based on judgment and skilled
interpretation of the actual processes taking place. The more comprehensive methods do also provide more information by means of
model parameters useful for the interpretation.
Experimental analysis of first foul flush in an industrial area. S. Artina; A. Bolognesi*+; T. Liserra; M. Maglionico; G. Salmoiraghi
Presented by Andrea Bolognesi, Università di Bologna, Italy
This paper is about a monitoring campaign carried out in a commercial-industrial site near Bologna, Italy. The experimental
catchment is part of a goods warehouse area, run over every day by several trucks. The watershed area is about 1.15 ha, almost
completely impervious, including a parking area and a charge-discharge zone for trucks and also a small part of the warehouse
building roofs. Storm water is collected by a small drainage system into a first foul flush tank, whose effective volume is about 36
m3. In order to study both hydraulic and water quality aspects, the site has been equipped with several instruments, like an
automatic sampler, a rainfall gauge, a submerged level sensor and a turbidity meter. Rainfall data, tank water level and turbidity
have been recorded continuously for 8 months; during that period 57 rainfall events (> 1 mm) have taken place (total rainfall of 451
mm). For 5 of those events, water samples were collected and analyzed to know chemical concentrations (SST, COD, metals and
hydrocarbons) and ecotoxic inhibition (Vibrio fischeri). Laboratory results have been compared to turbidity and hydrological values
recorded, in order to find possible relationships between punctual and continuous data.
Comparison between simulation tools on a small urban storm sewer network. S. Artina; A. Bolognesi; T. Liserra*+; M. Maglionico
Presented by Tonino Liserra, DISTART-CI Università di Bologna, Italy
The purpose of this article is to test the behaviour of two commercial models for the simulation of sewer systems (InfoWorks,
developed by Wallingford Ltd and Mouse, developed by DHI), basing on the experimental data sampled in a 1.15 ha watershed
located near Bologna, northern Italy. The experimental catchment is part of a truck transit and parking area, completely asphalt
paved and drained into a first flush tank. Hydrologic and water quality data collected for almost 8 months inside the tank, have been
necessary to calibrate the models through a trial and error procedure, for both quantity and quality aspects. A sensitivity analysis for
the most relevant quali-quantitative parameters has also been performed.
Prolonged deposition of heavy metals in infiltration facilities and its possible threat to groundwater contamination. R.K. Aryal+;
M. Murakami; H. Furumai; F. Nakajima*; H.K.P.K. Jinadasa
Presented by Rupak Aryal, University of Tokyo, Japan
Field investigation of the infiltration facilities, built two decades ago in Tokyo, was carried out and sediment samples were collected
from 12 infiltration inlets of three different locations. Heavy metals contents in the inlet sediment, road dusts and soils samples
were analyzed and compared. The particle size distribution analysis showed its variation with depth as well as from inlet to inlet.
The nature of organic substance present in sediment found changed with particle sizes as well as with depth. The heavy metals
content in the sediment samples ranged from 6~143 (Cr), 1~84 (Ni), 49~331 (Cu), 210~2186 (Zn) and 2~332 (Pb) µg/g. The heavy
metal content ranges were similar to the road dust, which indicated road dust as a possible source for sediment for the infiltration
inlets. The lower heavy metals content in many sediment samples than the soil indicated possible release/desorption of heavy
metals under newly created environment such as anaerobic environment. Among the heavy metals there was relatively good
relationship between Cu and Zn indicating the existence of their common sources.
Critical studies for predicting groundwater quality in Hyderabad urban area by integrating remote sensing and GIS. S. S. Asadi*+;
P. Vuppala; M. A. Reddy
Presented by Sivasankar Asadi, Jawaharlal Nehru Technological University, India
Ground water quality in Hyderabad has special significance and needs great attention of all concerned since it is the major alternate
source of domestic, industrial and drinking water supply. The present study is carried out to monitor the ground water quality with
respect to the land use change and to map such quality using Remote sensing and GIS techniques for a part of Hyderabad metropolis.
Thematic maps like base map, drainage and road network maps were prepared using SOI toposheets on 1:50,000 scale using AutoCAD
and ARC/INFO software. Land use/land cover map of the study area is prepared from the linearly enhanced fused data of IRS-ID PAN
and LISS-III imagery using visual interpretation technique. The ground water samples were analyzed physico-chemically for the
generation of attribute database. Based on the results of the analysis, maps showing spatial distribution of major water quality
parameters are prepared using curve fitting method in Arc View v3.1GIS software. Water Quality Index (WQI) in the study area was
determined to find out the suitability of water for drinking purpose. The results showed a high concentration of nitrates, hardness,
alkalinity and TDS in few areas of Zone-V which could be due to the present landform, dumping sites, seepage of waste and effluents
and also the weathering of mineral bearing rocks and leaching. The overall view of the water quality index of the present study zone
showed a satisfactory result with most of the study area with < 50 standard rating of water quality index except in places like
Yousufguda, Erragadda, Shaikpet and Hakimpet. Appropriate methods for improving the water quality in these areas have been
suggested.
9
Infiltration of a copper roof runoff through artificial barriers. K. Athanasiadis*+; B. Helmreich; P. A. Wilderer
Presented by Konstantinos Athanasiadis, Technical University of Munich, Germany
On-site infiltration of a copper roof runoff may contribute to deterioration of the ground and ground water. To avoid such a negative
effect the performance of two different technical systems, equipped with four different barrier materials, regarding copper
elimination was examined in a field study. During the period March 2004 to January 2005, sixteen rain events were examined. Copper
concentrations between 200 and 11,000 µg/l in the roof runoff during a rain event were observed. The cover material of the roof and
the drainage system were responsible for the high concentrations of copper in the roof runoff. It was evident that roof aspects facing
towards the wind direction were receiving higher rainfall, thus were establishing higher copper runoff rates. The retention facilities
have reached a performance up to 97 % regarding copper elimination.
Priority pollutants in urban runoff (on an example of Minsk city). A. Aucharova*+; V. Khomich
Presented by Alena Aucharova, Ins. for Problems of Natural Res. Use & Ecology, Belarus
An exploratory study of urban runoff contamination was undertaken at different functional zones (areas with different land use) in
Minsk, Belarus. Four seasonal field surveys describing two periods of storm runoff forming (winter-spring and summer-fall) were
realized. Water samples were collected from roadways (streets), shopping plaza, pavements, etc. The chemical composition of
runoff was determined for such water quality constituents as suspended solids, pH, main ions, heavy metals and oil products. In both
of the periods the samples of stormwater runoff from streets and pavements are contaminated most of all. Urban runoff contains
high concentrations of suspended solids (261.5–4277.8 mg/L) and has high solute content (140.1–8208.7 mg/L). The maximum
content of pollutants is revealed in water samples for a winter-spring period. During this period stormwater runoff contains a lot of
chlorides (805.1–5659.4 mg/L), natrium (610.0–3580.0 mg/L) and nitrites (0.2–1.4 mg/L), as a result of application of deicing agents
in a winter period (mixture of salt and sand). Oil products are one of priority pollutants of urban runoff from transport and
residential zones (11.7–42.5 mg/L). Concentrations of such heavy metals as zinc and copper reach 0.095–0.375 and 0.008–0.09 mg/L.
Turbidity monitoring in sewage. M. Aumond; C. Joannis*+
Presented by Claude Joannis, Laboratoire Central des Ponts & cCaussées, France
While standard pollution parameters such as SS or COD are widely used today, they can only be monitored by means of sampling
followed by laboratory analysis, which then becomes very costly if a high sampling rate is required. Some analysis set-ups are able to
perform a kind of continuous monitoring, yet both capital investment and operating costs remain high. When it comes to monitoring
pollutant concentration in sewage, the turbidity parameter is worth considering. Although its “translation” into standard parameters
is not entirely accurate, turbidity can still be used as a pollutant indicator on its own and provides for continuous monitoring at low
cost. In this paper, we will study on a specific site how continuous turbidity monitoring may be achieved in practical terms through
use of an adapted real-time filtering scheme; we will also present an initial data analysis, focusing on the behaviour of turbidity
during dry weather.
Australian rainfall & runoff - Guiding Australian practice into the 21st century. J. E. Ball*+; B. C. Phillips+
Presented by James Ball, UNSW, Australia
Since 1958 when Australian Rainfall and Runoff was first released it has remained one of the most influential and widely used
guidelines published by Engineers Australia. The current edition, initially published in 1987 and in a split book form in 1998, has
received widespread Australian and international acclaim. The issues of environment sustainability and water conservation are
increasingly requiring the application of updated or new engineering hydrology techniques. Consequently a new updated and revised
edition of Australian Rainfall and Runoff is under preparation. The evolution of Australian Rainfall & Runoff is overviewed and the
current on-going review is discussed. The inclusion of new information on the hydrology of rainfall and runoff for water quality
investigations in both urban and rural areas, the use of catchment simulation techniques, the integration of hydrologic and hydraulic
models, and hydrological aspects of integrated water management within urban areas is overviewed. It is concluded that the current
review of Australian Rainfall & Runoff demonstrates the commitment the NCWE and the many authors to maintaining it as the preeminent guideline for hydrology and hydraulics in Australia into the 21st century. It also provides a model for other countries who
are preparing national guidelines for hydrological and hydraulic practices.
A modelling tool for assessing flood risk. D.J. Balmforth*; P. Dibben+
Presented by Peter Dibben, MWH, United Kingdom (Great Britain)
Managing urban flooding remains one of the key challenges for the operators of sewerage systems in the developed world. In the UK
it has been an important area of investment over the last five-year asset management period, and will be even higher on the agenda
for the next five. Although modern software tools are extremely sophisticated in estimating the probability of sewer surcharging and
surface flooding, the science of assessing individual property flood risk is still in its infancy. The authors have developed a flood risk
tool to identify the consequential effects of sewer system overloading in terms of individual property flood risk. This is postprocessing software using the output from conventional modelling software. The tool recognises two separate causes of property
flooding: backing up flow through connecting drains when sewers are surcharged, and the conveyance of flood flows over the
surface. The severity of each is combined with return period to give a flood risk score for each property within a catchment. The tool
has been trialled by UK water companies as a proactive way of managing flood risk and has been shown to offer significant
advantages over traditional methods of urban flood management.
Development of an On-site Stormwater Management Information System for the Emscher Drainage Basin. S. Bandermann*+; B.
Spengler
Presented by Stephan Bandermann, Ing. Ges. Prof. Dr. Sieker mbH, Germany
In the urban area of the Emscher drainage basin with 19 participating communities, the sewer system will change completely within
the next 15 years. One part of the change will be the area-wide application of on-site stormwater systems. This requires different
master planning compared to earlier conventional planning. The on-site measures will be implemented gradually and will last for the
next 15 years. One main aspect is the development of an On-site Stormwater Management System. For this different tools were
developed and a concept is being elaborated upon. Major parts of the internet based On-site Stormwater Information System will be
the preparation of maps available for the concernd communities. Another aspect is a collection of GIS-based analyse tools for
updating maps and their database. Part of it will be a decision tree, a GIS-based flexible expert system, which can automatically
update maps that will be presented on the World Wide Web so the participating communities can get easy access to new planning
developments.
Bottom shear stress in unsteady sewer flow. V. Bareš*+; J. Jirák; J. Pollert
Presented by Vojtech Bares, Czech Technical University in Prague, Czech Republic
The properties of unsteady open-channel turbulent flow were theoretically and experimentally investigated in a circular cross
section channel with fixed sediment deposits. Velocity and turbulence distribution data were obtained using an Ultrasonic Velocity
Profiler (UVP). Different uniform flow conditions and triangular-shaped hydrographs were analysed. The hydrograph analysis revealed
a dynamic wave behaviour, where the time lags of mean cross section velocity, friction velocity, discharge and flow depth were all
evident. The bottom shear stress dynamic behaviour was estimated using four different approaches. Measurements of the velocity
10 10th International Conference on Urban Drainage – Abstract collection
distribution in the inner region of the turbulent layer and of the Reynolds stress distribution in the turbulent flow provided the
analysed data sets of the bottom shear stress. Furthermore, based on the Saint Venant equation, the bottom shear stress time
behaviour was studied using both the kinematic and the dynamic flow principles. The dynamic values of the bottom shear stress were
compared with those for the steady flow conditions. It is evident, that bottom shear stress varies along the generated flood
hydrograph and its variation is the function of the flow unsteadiness. Moreover, the kinematic flow principle is not an adequate type
of approximation for presented flow conditions.
Fuzzy-logic assessment and ageing forecast of sewers. R. Baur*+; R.T. Alvarez; A. Lipkow
Presented by Rolf Baur, TU Dresden, Germany
A fuzzy logic based approach is presented for the condition grading of defect sewers. Different failure types are not aggregated, but
analyzed separately and in detail. The deterioration process is simulated by a time continuous Markov chain approach for two ageing
paths: with respect to rehabilitation priorities, and with respect to the intrinsic or substantial value of the sewer pipe. For the short
term forecast, the probability of entering a certain condition grade is calculated, whereas for the purpose of a long term
rehabilitation strategy, the probability of the resistance time of a pipe within a particular condition grade is considered. The
condition forecast is beneficial for setting up inspection plans, scheduling rehabilitation work, and calculating future investment
needs for rehabilitation. Compared to other models the presented approach distinguishes between the long term and the short term
forecast. The detailed analysis of inspection data, before it is aggregated to condition grades enhances the forecast result, and
improves significantly the practical relevance of ageing models for the rehabilitation management of sewer networks.
Nutrient removal from stormwater detention ponds in subtropical Australia: pulling apart the 'black box'. M.L. Bayley*; M.
Greenway+; P.C. Pollard
Presented by Margaret Greenway, Griffith University, Australia
Many councils and management authorities within Australia are beginning to take steps to ameliorate downstream ecosystem affects
of stormwater by creating treatment systems within individual catchments and sub-catchments. Commonly, detention ponds and
wetlands are used in subtropical Australia as a means of both storing and treating stormwater before in reaches downstream
receiving waters. The ability of detention ponds to store and treat stormwater is well document, but past research lacks the insight
into how detention ponds treat the stormwater. This research paper investigates questions of how, where and why inorganic
nutrients are removed in stormwater detention ponds. Phytoplankton and Bacterioplankton were found to remove a significant
amount of inorganic nutrients from the water column within the studied detention basin, with large bacterioplankton productivity
indicating a huge internal nutrient source. While the stormwater detention pond studied showed considerable amount of treatment
during a monitored flood event, it also showed a considerable amount of ‘un traced’ inorganic nutrient sources and sinks. These un
traced sources and sinks essentially cloud the true removal potential (or performance) of detention ponds, making it difficult to
assess the true inorganic nutrient removal ability of stormwater detention ponds.
Pervious pavement research in Spain: Hydrocarbon degrading microorganisms. J. R. Bayón*+; D. Castro; X. Moreno-Ventas; S.J.
Coupe; A.P. Newman
Presented by Joseba Rodríguez Bayón, Universidad de Cantabria, Spain
Pervious pavements have made an important contribution to stormwater quality improvements in sustainable urban drainage
systems, particularly as part of a treatment train approach. In Spain however this approach has hardly been addressed. This paper
outlines the emerging research in a collaboration between UK and Spanish Universities aimed at establishing a research
infrastructure to allow the study of pervious pavements to be carried out taking into account local conditions in the northwest of
Spain. Parallel with the development of locally-appropriate porous pavement structures a biological study dealing with the
hydrocarbon degrading efficiency is taking place. Experiments are reported utilising different locally available surfaces and sub-base
materials in which microorganisms are introduced from a variety of contaminated sites to act as an inoculum. In addition to effluent
analysis aimed at measuring the degree of hydrocarbon retention/degradation, experiments will be reported on the physical
characteristic of the different materials used. This research addresses the influence, not only of the different surface and sub-base
materials but also of the different types of geosynthetics used. It is intended that this research will establish criteria for the further
development of a design for hydrocarbon-degrading pervious pavement structures in Spain.
Colloidal speciation of heavy metals in runoff and interstitial waters of a retention/infiltration pond. B. Bechét*+; B. Durin; M.
Legret; P. Le Cloirec
Presented by Beatrice Bechet, Laboratoire Central des Ponts et Chaussees, France
The thickness of non saturated zone and physico-chemical conditions are important parameters to assess the impact of infiltration
ponds on water resources with respect to heavy metals transfer. As changes in physico-chemical parameters of solutions have a
strong impact on the mobility of colloidal phases in sediments and soils, the colloidal facilitated transfer of heavy metals has to be
investigated. Therefore, this study focuses on the characterization of runoff, surface and interstitial waters in a
retention/infiltration pond collecting runoff waters of a bridge near Nantes. Physico-chemical parameters and chemical analyses
were performed on the waters during about one year. The separation of dissolved and colloidal fractions was carried out by filtration
and ultrafiltration for one sample of surface and interstitial waters. Until now, the runoff waters were only filtered at 0.45 µm. The
comparison of physico-chemical data shows that the minor variations of runoff water parameters are mitigated in basin and in soils
but strong variations impact the composition of interstitial waters. High concentrations of zinc, copper and still of lead are measured
in runoff. Lead and cadmium seem to be associated to colloidal and particulate fractions while zinc, copper, nickel and chromium
are distributed in all fractions.
A coupled sewer system and WWTP modelling approach to minimise annual discharge: a case study. C. Beck*+; K. Le Roy; A.-G.
Sadowski
Presented by Christian Beck, ENGEES, France, Metropolitan
Urban rainy weather effluents, in spite of dilution effects, could represent a major cause of pollution for receiving water when
directly rejected at CSO’s or inducing wastewater treatment plant malfunction, conducting to immediate or cumulative impacts. In
this study, we reconsider the operating mode of an activated sludge wastewater treatment plant (WWTP) and the dimensioning of its
storm basin, seeking to minimise total rejected flows at annual scale, while maximising rainy weather flows through these two
works. The total annual flow rejected by these two works constituted the principal criterion to discriminate various scenarios.
A stormwater management information system for the catchment area of the river Emscher. M. Becker+; G. Geretshauser*; B.
Spengler; H. Sieker
Presented by Michael Becker, Emschergenossenschaft, Germany
In order, in the course of remediating the Emscher river system, to reinforce the ecological potential and the municipal landscaping
benefits of the new bodies of water and to limit the costs for technical stormwater management measures, great importance has
been attached to coping with stormwater via surface seepage. The potential of such measures depends on many different factors of
influence. Consequently it makes sense to prepare a systematic classification for checking and evaluating the use of decentral
stormwater management systems. When sufficient data is available, geographical information systems can support the planning of
11
stormwater management measures. In the past, there has been a lack of across-the-board data and evaluations as well as of
information on the peripheral conditions and factors resulting from the structure of individual built-up areas. This gap will be closed
with the stormwater management information system. The data pool that has been built up contains statements on all the peripheral
conditions and factors relevant for deciding on the type and potential of close-to-nature stormwater management methods. The
stormwater management information system makes it possible for concepts covering complete catchment areas to be developed and
their effectiveness to be evaluated via one single system.
International urban drainage research database. T. Beenen*; G. Vaes; R. Bouteligier+; R.G. Veldkamp
Presented by Raf Bouteligier, K.U.Leuven - Hydraulics Laboratory, Belgium
The RIONED Foundation (www.riool.net) is the national not-for-profit knowledge centre on sewer systems and urban drainage in The
Netherlands. RIONED contracted the University of Leuven and the Delft University of Technology to develop a database on the
published results of research projects in the field of urban drainage. The database must give insight in the state of the art of the
research in this field, the centres of knowledge on specific themes and must open up the literature to support desk studies. RIONED
aims at avoiding double research and better accessibility of literature and centres of specific knowledge. The database will be
accessible through the Internet and should be updated regularly to ensure the actuality of the database. To be able to use the
database for programming research ongoing research projects should be added too. Therefore a plea is made for the development of
a structure for collaboration of knowledge centres. Within this structure the database can be extended and kept up-to-date.
Organisations interested to join the development of such a structure should give notice on the RIONED website www.riool.net by
following the ‘English’-link.
SPIRIT: Towards an interactive tool for predictive asset management of sewer systems. A.S. Beenen*+; H. Vis; P. J. Van Gestel; A.
Rabenort
Presented by Ton Beenen, RIONED, Netherlands
SPIRIT is an interactive tool for predictive asset management. SPIRIT is a software plug-in for sewer management packages that
uploads the actual state and environmental factors to a central databaseon the Internet. SPRIT downloads the prediction of the
sewer condition in 5 respectively 10 years from the uploaded actual state. This interactivity improves the model by a self learning
proces and results in a typical win-win situation. The RIONED Foundation is the national not-for-profit knowledge centre on sewer
systems and urban drainage in The Netherlands. RIONED contracted Covalent ITS and Delta Pi to develop a roadmap towards an
interactive tool for predictive asset management of sewer systems. Predictive asset management can become the next step towards
costs- and risks- optimized planning of Operation and Maintenance (O&M) measures in sewer systems. Therefore, expert judgement
and statistics have been combined to predict the probabilistic development of the condition of the sewer systems. The predictive
asset management tool can become self learning as an interactive website extends the underlying database on a give and take basis.
This paper describes the project called SPIRIT (Dutch acronym for software plug-in for interactive prediction of sewer condition) and
recent results obtained.
On an application of extended Kalman filtering to activated sludge processes: A benchmark study. F. Benazzi*+; U. Jeppsson; R.
Katebi
Presented by Farid Benazzi, University of Strathclyde, United Kingdom (Great Britain)
The growing demand for performance improvements of urban wastewater system operation coupled with the lack of instrumentation
in most wastewater treatment plants motivates the need for non-linear observers to be used as virtual sensors for estimation and
control of effluent quality. This paper is focused on the development of a general procedure for on-line monitoring of activated
sludge processes, using an extended Kalman filter (EKF) approach. The Activated Sludge Model no.1 (ASM1) is selected to describe
the biological processes in the reactor. On-line measurements are corrupted by additive white noise and unknown inputs are
modelled using fast Fourier transform (FFT) and spectrum analyses. The given procedure aims at reducing the original ASM1 model to
an observable and identifiable model, which can be used for joint non-linear state and parameter estimations. Simulation results are
presented to demonstrate the effectiveness of the proposed methods and show that on-line monitoring of SND and XND
concentrations is achieved when dynamic input data are used to characterize the influent wastewater for the model.
Assessment of WWTP design and upgrade options: balancing costs and risks of standards' exceedance. L. Benedetti*+; D. Bixio, P.
A. Vanrolleghem
Presented by Lorenzo Benedetti, Ghent University, Belgium
Numerical models can be used to evaluate design and upgrade scenarios of urban wastewater systems on the basis of their ecological
consequences. The objective of this paper is to illustrate a systematic procedure of system design/upgrade. This procedure consists
of the following steps: 1) data collection and data reconstruction, 2) model building and calibration, 3) evaluation of scenarios, 4)
uncertainty assessment. In contrast to conventional practice, this approach allows to choose the most appropriate trade-off between
cost of measures and risk of non-compliance with regulatory limits. An example of its application dealing with the assessment of
WWTP design and upgrade options is provided. Results show that by reducing the tank volumes compared to conventional design
procedures, costs can be reduced sensibly while the risk of not meeting legislative requirements are only slightly increased.
Removal of heavy metals and PAH in highway detention ponds. T.R. Bentzen+; T. Larsen*; S. Thorndahl; M.R. Rasmussen
Presented by Thomas Ruby Bentzen, Aalborg Universitet, Denmark
The paper presents some of the first results from a study of the removal of pollutants in highway detention ponds in Denmark. The
objective of the study is to set up a procedure for long-term modelling of discharges of pollutants to the environment from the many
Danish highway detention ponds, which has been designed according to standard design criteria for several decades. The study will
focus on heavy metals (Cd, Cr, Cu, Pb and Zn) and polyaromatic hydrocarbons (PAH). The long-term simulation of input of flow and
pollution to the ponds will be a hindcast based on time series of historical rainfalls. The modelling will take place in a special version
of the MIKE URBAN. The modelling is calibrated and validated on measurements from selected highway catchments. The removal of
pollutants in the ponds is studied by measurements and CFD modelling using the MIKE 21 and MIKE 3 numerical models.
Long term monitoring of sewer sediment accumulation and flushing experiments in a man-entry sewer. J. Bertrand-Krajewski*+;
J. P. Bardin; C. Gibello
Presented by Jean-Luc Bertrand-Krajewski, INSA de Lyon, France
The paper presents continuous field experiments carried out during 4 years in a man-entry egg-shape combined sewer in Lyon,
France in order to contribute to the knowledge and the modelling of: i) sediment accumulation and ii) sediment removal by means of
a Hydrass flushing gate. The 250 µm sediments are mainly mineral, and their physical and chemical characteristics appear as rather
stable in time and space. Long-term sediment monitoring reveals: i) a regular asymptotic increase of both the sediment mass and the
slope of its longitudinal profile, ii) a clear correlation between local sediment profile irregularities and sewer ancillaries but without
significant influence on the global and long term general accumulation. Simple sediment accumulation modelling shows: i) a good
suitability of a three parameters conceptual model to reproduce asymptotic sediment volume accumulation, and ii) a good suitability
of the Velikanov model to reproduce sediment profiles. Both models reproduce observations with an acceptable margin of
uncertainty for operational management purposes but are very sensitive to input data and parameter values. The Hydrass flushing
gate is efficient and it appeared that the mass of sediments moves downstream linearly with the number of flushes.
Towards a better knowledge and management of infiltration and exfiltration in sewer systems: the APUSS project. J. L.
Bertrand-Krajewski*+; M. A. Cardosa; B. Ellis; T. Frehmann; M. Giulianelli; W. Gujer; P. Krebs; Z. Pliska; J. Pollert; K. Pryl
Sewer systems constitute a very significant patrimony in European cities. Their structural quality and functional efficiency are key
parameters to guarantee the transfer of domestic and trade wastewater to treatment plants without infiltration nor exfiltration.
Infiltration of groundwater is particularly detrimental to treatment plant efficiency, while exfiltration of wastewater can lead to
groundwater contamination. During the period 2001-2004, the European research project APUSS (Assessing infiltration and
exfiltration on the Performance of Urban Sewer Systems) was devoted to sewer infiltration and exfiltration questions. It was
structured on three main Work Areas dealing respectively with i) the development of new measurement methods based on tracer
experiments and accounting for detailed uncertainty analyses, ii) the implementation of models and software tools to integrate
structural and experimental data and to facilitate data display, operational management and decision making process and iii) the
integration of economic and operational questions by means of costs estimation, economic valuation, performance indicators and
multi-criteria methods applied to investment/rehabilitation strategies. This overview paper describes synthetically the objectives,
methods and main achievements for each Work Area. References to both antecedent and companion papers are given for results and
more detailed information.
Exfiltration from sewers - Is it a serious problem?. D. Blackwood*+; D. J. Gilmour; J. B. Ellis; D. M. Revitt; A. Stainess
Presented by David Blackwood, University of Abertay Dundee, United Kingdom (Great Britain)
This paper contends that estimates of exfiltration leakage from sewers, and the problems arising from it may be too high due to an
underestimation of the “self-repairing” action of sewage and sewage sediments in raw sewage. Two aspects of a continuing
programme of research are reported; (i) the measurement of exfiltration rates from a range of defects in a sewer pipe with pipe
bedding effects simulated by a dry gravel trench surround to the pipe, and (ii) an assessment of the persistence of pathogens in the
gravel and soil beneath the test rig pipe, using coliforms as a biological indicator. The results show that the introduction of a gravel
surround resulted in more rapid and effective sealing across the entire range of defects tested compared to previously performed
experiments with the defects discharging to air. Complete sealing eventually occurred on every run for a 10 mm x 10 mm defect
situated at the invert of the sewer and the lowest recorded levels in each experiment for a 10 mm wide radial defect were of the
order 10-3 to 10-4 l s-1. These results have been scaled-up to estimate leakage rates in lengths of sewers and sub-catchments and
levels significantly lower than previously estimated are indicated. Additionally, the pilot experiment to investigate the fate of
biological contaminants in the exfiltrate suggests rapid reduction in microorganisms levels beneath the sewer pipe.
Loss models - an evaluation of the probability of antecedent rainfall prior to significant rainfall events in Sydney, Australia. J.
Blaikie; J. E. Ball*+
A common approach for the assessment of flood risk associated with a proposed development in a flood-prone area is the utilisation
of a catchment modelling system. Numerous alternative hydrologic and hydraulic process models have been proposed for inclusion in
these systems of process models. In a similar vein, a number of alternative rainfall models for the description of the spatial and
temporal variation of rainfall have been proposed. Previous studies such as those by Walsh et al. (1991) and Hill et al. (1996) have
shown the importance of the loss model, or the model by which water is removed from rainfall to produce potential surface runoff.
While previous studies have indicated the importance of loss models in the estimation of a design flood flow with a pre-defined
annual exceedance probability, little information has been developed to assist modellers with the task of converting rainfall of a
given annual exceedance probability into flow with the same exceedance probability through the application of catchment modelling
systems. Furthermore, even less information has been presented on the magnitude of likely antecedent conditions and the variation
of these conditions with the desired annual exceedance probability. Presented in this proposed paper will be an analysis of rainfall
across Sydney with the aim of developing the most likely antecedent conditions prior to a rainfall event of a defined annual
exceedance probability. It will be shown that these conditionsvary across the Sydney
region and that a single design value is unlikely to be appropriate.
Framework for water and flood risk management in the City of Bradford. J. Blanksby*; A. Saul; R. Ashley; A. Cashman; T. Poole;
D. Melling
Presented by Richard Ashley, University of Sheffield, United Kingdom (Great Britain)
Fluvial and pluvial flooding in recent years within Bradford has resulted in the establishment of an independent enquiry into flood
management by the District Council. The enquiry has identified a number of issues that must be addressed if the Council and the
other key stakeholders are to act effectively to reduce the impact of flooding. The Council is working alongside researchers and
other partners in research projects to improve flood risk management and to investigate the impact of climate change on urban
storm drainage. Two EU funded Interreg projects in which the Council is a partner are providing data inputs and case study sites for
the research. A strategic approach to urban flood risk management is being developed and this is compatible with proposals set out
in a recent Government consultation document (Defra, 2004). The formulation of the strategic approach and the case studies have
helped to identify end user requirements for the research outputs. It has also helped to identify the institutional barriers within an
integrated framework. It will be necessary for the government and other national stakeholders who develop policy and control
funding to take appropriate action if an effective integrated approach is to be adopted.
Linking imperviousness coefficient to urbanism features through Geographical Information Systems. P. Bordin*+; M. Mayeux; O.
Bonin; J. C. Deutsch
Presented by Patricia Bordin, IGN, France
One of the major problems in the modeling of stormwater runoff is the determination of the rainfall excess. For very long time urban
hydrologists have used the concept of run-off coefficient which gives an order of magnitude of run-off losses. In dense urban areas,
the imperviousness area is used to approximate this run-off coefficient. There are two advantages to this approach: the ability to
have a measured value independent from the rain event, and the ability to make a link with the characteristics of urbanism. Many
researchers have tried to establish relations between the imperviousness coefficient and parameters such as: type of roofs for the
buildings, kind of road systems (streets, pavements, places etc.), kind of public spaces (waste ground, green spaces, playground
etc.). Empirical relations have been established, but in the best cases they were just valid for the sites where they have been
implemented. New kinds of GIS have been developed in France which enable to search general relationship between imperviousness
coefficient and urban parameters, in order to better calculate this coefficient for present urbanization and to predict its value for
future urbanization.
Wastewater and storm water drainage systems in Kolkata a special note on current happennings. S. Bose*+
Presented by Shivashish Bose, Jadavpur University, India
13
Situated between the tidal river Hugli on the west, the overflowing swamps on the east, and having tidal creeks surrounding, Kolkata
suffered chronically from drainage congestion and water logging, especially during monsoon period with large run-off. The city
proper has a combined sewer disposal system laid in west to east direction as per natural slope of the basin, and the drainage is
disposed through channels and canals to river Kulti, which carries the discharge to Bay of Bengal. The added areas lack proper
central sewerage collection system by the municipality and sewage management is done by septic tank, surface drain, conduits laid
underground and deposited to the canals and local ponds resulting in pollution and health hazards. Works have been done following
reports of World Health Organization, Central and State Government Organizations. However, the results have not been totally
satisfactory due to many factors on the face of tremendous force of unprecedented urbanization. Recently, increasing awareness
about environment, pollution and sustainability has generated some actions taken up for better drainage solution in an integrated
manner. The municipality and local government are introducing measures which are anticipated to minimise the adverse impacts on
environment.
The Flemish CSO monitoring network revisited. R. Bouteligier*+; G. Vaes; J. Berlamont
Presented by Raf Bouteligier, K.U.Leuven - Hydraulics Laboratory, Belgium
In 1998 a combined sewer overflow (CSO) monitoring network was established by the Water division of the Administration of
Environment, Nature, Land and Water Management AMINAL (Ministry of Flanders, Department of Environment & Infrastructure). At
the end of the measuring campaign 19 CSOs were being monitored. As a result data for five consecutive years are available at a
number of CSO locations. This paper presents the results of a research project carried out by the Hydraulics Laboratory of the
University of Leuven (K.U.Leuven) in which the monitoring data that were collected throughout the years were evaluated. Analysis of
the measured data reveals that, for the larger part of the monitored CSOs, it often not suffices to merely measure the water level in
the CSO chamber during overflow events. Also measurements of, or data about, the throughflow at the CSO and the water level in
the receiving watercourse are needed in order to thoroughly evaluate the functioning of the CSO in terms of average spill frequency,
spill flow rate and spill volume. Long term simulations indicate that, due to the annual rainfall variability, a CSO has to be monitored
for several years in order to obtain a reliable, average CSO spill frequency.
Modular sewer quality simulation. J.B. Boxall*+; W.J. Shepherd; A.J. Saul; D.S. Hanson
Presented by Joby Boxall, Pennine Water Group, University of Sheffield, United Kingdom (Great Britain)
The prediction of sewer flow quality in combined sewer systems under storm conditions is becoming increasingly important to the
international water industry as there is a need to minimise environmental impact and to meet ever increasingly stringent regulatory
requirements. Software to simulate the behaviour of combined sewers under storm conditions is now available and has been
successfully applied to a variety of catchments. However, in many cases there are known limitations in the application and use of
such models, particularly with respect to the simulation of quality performance. These limitations relate primarily to the complexity
of the processes, systems and the time required to investigate the impact of design options. There is therefore scope to develop
new, simplified approaches that are able to simulate sewer flow quality at times of storm. Such models are required to reduce
computational times, while being efficient and equally as accurate as the conventional models. The development of such a modelling
tool is presented in this paper, together with results of preliminary testing undertaken on a 285 ha catchment in the North of
England. Results show favourable comparison between measured and simulated data.
Stormwater particles and their sampling using passive devices. I. M. Brodie*+
Presented by Ian Brodie, University of Southern Queensland, Australia
Total Suspended Solids (TSS) is commonly used as a measure of particle concentration in stormwater. The breakdown of TSS into
subgroups based on particle size is an important step in describing stormwater characteristics. A simple classification system is
proposed that divides solids into four size ranges; Very Fine (VFPs, <8µm), Fine (FPs, 8-63µm), Medium (MPs, 63-500µm) and Coarse
Particles (CPs, >500µm). The use of passive samplers to obtain unbiased, flow-weighted samples of non-Coarse particles was
investigated. Two alternative passive samplers referred to as a flow splitter and an orifice and weir device were designed,
constructed and tested. The flow splitter outperformed the orifice and weir device in terms of sampling accuracy. Based on
hydraulic testing up to 5 L/s, the flow splitter was able to accurately (±2% error) obtain a constant sample volume: flow volume ratio
compared to a ±15% error for the orifice and weir. Based on sediment testing, the performance of the flow splitter in obtaining VFP
and FP samples was similar to that of high frequency grab sampling. Samples collected by the flow splitter matched theoretical
concentrations of particles less than 63µm to within ±2% error. All sampling methods significantly underestimated the concentration
of particles greater than 63µm (MPs) and more research is needed in this area. Overall, the flow splitter is considered to have
significant potential for determining the Event Mean Concentration of stormwater particles.
A new overflow measurement device. H. Brombach*+; G. Weiss
Presented by Hansjoerg Brombach, UFT Umwelt- und Fluid-Technik GmbH, Germany
A new broad-crested type of a wing-shaped overflow weir was developed and calibrated to meet the needs of monitoring combined
sewer overflows in urban drainage systems. The main problem with existing sharp-crested weirs are hysteresis and inaccuracy at low
overflow heads. The airfoil type weir shows a very broad measurement range from Qmin/Qmax of about 1/10,000. Rating curves
calibrated in the hydraulic laboratory with and without upstream scumboards are introduced. The weir profile is bent from polished
stainless-steel sheet metal and is corrosion-proof. This new device fits best to the needs of CSO-control.
Feasibility of roof water harveseting in a cold climate. M. Brown*; N. Lo; M. B. Liebman; L. J. D. Roach+; R. B. Staples
Presented by Leanne Dallmer Roach, STORM Consulting, Australia
Faced with mounting security of supply issues, the water supply authority in an Australian snowplay resort is trialling roof water
harvesting to reduce mains water demand. A trial was established to harvest roof water from a building in Perisher Valley, New South
Wales with both a roof and ground collection system. While the trial is ongoing, results from June 2004 to January 2005 show that
the ground and roof collection systems collected approximately 100kL and 81kL respectively. Analysis of water quality analysis also
indicated that with no treatment, the collected water complied with Australian Drinking Water Guideline requirements, though it did
have some bacterial contamination. The results provide encouragement that roof water harvesting is a viable and sustainable
alternative to reducing mains water demand in alpine/cold climates.
Implementation impediments to institutionalising the practice of sustainable urban water management. R.R. Brown*; L. Sharp,
R.M. Ashley+
Presented by Richard Ashley, University of Sheffield, United Kingdom (Great Britain)
It is now well accepted that there are significant challenges to realizing the wide-spread and self-sustaining implementation of
sustainable urban water management. It is argued that these challenges are entrenched within the broader socio-political
framework, yet often unsuccessfully addressed within the more narrow scope of improving technical knowledge and design capacity.
This hypothesis is investigated through a comparative analysis of three independent research projects investigating different
dimensions of the water cycle including stormwater management in Australia, and sanitary waste management and implementation
of innovative technologies in the UK. The analysis reveals significant and common socio-political impediments to improved practice.
It was evident that the administrative regime, including implementing professionals and institutions, appears to be largely driven by
an implicit expectation that there is a technical solution to solve water management issues. This is in contrast to addressing the
issues through broader strategies such as political leadership, institutional reform and social change. It is recognised that this
technocratic culture is inadvertently underpinned by the need to demonstrate implementation success within short-term political
cycles that conflict with both urban renewal and ecological cycles. Addressing this dilemma demands dedicated socio-technical
research programs to enable the much needed shift towards a more sustainable regime.
Facilitating local organisational development for advancing sustainable urban water futures. R. R. Brown*+
Presented by Rebekah Brown, Monash University, Australia
This paper presents the local institutional and organisational development insights from a five-year ongoing interdisciplinary research
project focussed on advancing the implementation of sustainable urban water management. While it is broadly acknowledged that
the inertia associated with administrative systems is possibly the most significant obstacle to advancing sustainable urban water
management, contemporary research still largely prioritises investigations at the technological level. This research is explicitly
concerned with critically informing the design of methodologies for mobilising and overcoming the administrative inertia of
traditional urban water management practice. The results of 14 in-depth case studies of local government organisations across
Metropolitan Sydney primarily reveals that the political institutionalisation of environmental concern, and commitment to local
leadership and organisational learning are key corporate attributes for enabling sustainable management. A typology of five
organisational development phases has been proposed as both a heuristic and capacity benchmarking tool for individual
practitioners, and local and state government program designers for improving the level of local implementation of sustainable urban
water management activity. While this investigation has focussed on local government, these findings do provide guideposts for
assessing the development needs of future capacity building programs across a range of different institutional contexts.
The effect of combined wet weather sewage quality on the biological treatment process. Case study of Lodz. A. Brzezinska; M.
Zawilski*+
Presented by Marek Zawilski, Technical University of Lodz, Poland
In the paper, quality of combined sewerage inflow in the aspect of biological treatment was analysed. Proportion of quality
parameters and fractions of COD and TKN as well as alkalinity in the inflow to the Group Wastewater Treatment Plant in Lodz were
determined. The research revealed a distinct increase of inert fractions during wet weather caused by an increasing portion of
contaminants attached to suspended solids. Modelling of the biological process made it possible to investigate the effect of the raw
wastewater quality variations on the effluent quality. This effect turned out to be significant when average effluent parameters like
COD and total nitrogen are concerned.
A Canadian experience – InfraGuide. B. M. Buberoglu*+
Presented by Bilgin Buberoglu, National research Council Canada, Canada
The National Guide to Sustainable Municipal Infrastructure (InfraGuide) is a unique Canadian information resource for infrastructure
project decision makers. It is funded mainly by Infrastructure Canada and managed jointly by Federation of Canadian Municipalities
and National Research Council Canada. Other stakeholders augment the available funds for the project by their in-kind contributions
through volunteers taking active parts in InfraGuide activities. InfraGuide has 5 Technical Committees currently each working on one
of the following municipal infrastructure areas or activities; municipal roads and sidewalks, potable water, storm and wastewater,
environmental protocols, and decision-making and investment planning. InfraGuide published to date over 50 Best Practice
documents in total, covering these five domains. Published three documents pertaining to urban drainage issues cover most of the
treatment train concept for urban drainage. The “Stormwater Management Planning” sets the stage for an integrated stormwater
management planning approach, which considers stormwater as a resource to be protected. “Source and On-Site Controls for
Municipal Drainage Systems” introduces the rationale of stormwater management programs. “Conveyance and End-of-Pipe Measures
for Stormwater Control” sets its objectives as both prevention and mitigation of stormwater run-off quantity and quality impacts and
explains a variety of methods and mechanisms to be applied.
Development patterns of Nineteenth Century water and wastewater infrastructure in the United States. S.J. Burian*+; F.G.
Edwards; T.N. McPherson
Presented by Steven Burian, University of Utah, United States of America
This paper highlights the development of water supply and wastewater collection infrastructure in the United States (US) during the
nineteenth century, focusing on the interrelationship between the two systems. The factors that influenced the development
patterns are briefly presented and the legacy of the systems developed in the past on current and future urban water and
wastewater managers is discussed. Numerous factors may be identified that guided past water and wastewater infrastructure
decisions and contributed to the creation of the foundation of most modern water and wastewater infrastructure systems in major
US cities. The factors this paper presents include population dynamics, water/wastewater paradigm and infrastructure technology
status, status of scientific understanding, socioeconomic, institutional, climate, and physical setting. Past water and wastewater
infrastructure choices have in many cases created the heart of modern systems and thus have influenced current environmental
problems (e.g., combined sewer systems) and operation and management issues and will likely do so for the foreseeable future.
Sewer rehabilitation planning – priority and cost planning using GIS. R. Burkhard*+; S. G. Lakehal
Presented by Roland Burkhard, ERZ, Switzerland
Rehabilitation priority and cost planning are an important and integral part of urban drainage master planning in Switzerland.
Although Entsorgung + Recycling Zürich (ERZ), the sewer-age utility of the city of Zürich, has considerable financial means available
for the rehabilita-tion of its sewers, it has so far not established a continuous leading role in triggering rehabilitation projects among
the city’s utilities departments, which results in a suboptimal qualitative improvement of the sewer network. This was due to
organisational as well as technical rea-sons. It was thus decided in late 2003 to develop a decision support tool for rehabilitation and
cost planning, which visualises the most urgent rehabilitation needs. A lot of data necessary for rehabilitation and cost planning is
readily available on different databases and servers, but was so far never linked to provide a semi-automatic tool that combined all
the information. This paper describes the basics and the methods for the design of a rehabilitation- and cost-planning prototype.
A Decision Support System for Urban Groundwater Resource Sustainability. S. Burn*+; D. DeSilva; M. Ambrose; S. Meddings; C.
Diaper; R. Correll; R. Miller; L. Wolf
Presented by Stewart Burn, CSIRO, Australia
This paper discusses the development of a computer based software tool to generate groundwater contaminant data; that can be
utilised in the sustainable management of water resources; in urban areas reliant on groundwater. The tool incorporates several
models, including a model for simulation of the integrated urban water system within an urban area to estimate contaminant loads,
a model that estimates the extent of leakage from sewer pipelines and two unsaturated transport models which trace the
attenuation of contaminants and movement of water through the soil to the aquifer. The output from the tool is data suitable for use
in commercially available groundwater flow models to allow prediction of contaminant flows within the aquifer, as well as sufficient
data to allow socio-economic analysis of different scenarios. The urban water system tool allows water services to be represented in
a flexible manner and provides the ability to represent and investigate the implications of a wide range of conventional and
15
emergent techniques for providing water supply, stormwater and wastewater services. This allows the users to process predefined
scenarios, and provide options to the end-user to develop best practice response to the scenario based on the scenarios potential for
groundwater contamination. For example modifying customer preferences, groundwater treatment or introducing system
improvements that minimise contamination.
Treatment of CSO water using floating plant beds. L. Buts*+; C. Thoeye; G. De Gueldre
Presented by Ludwig Buts, Aquafin NV, Belgium
A pilot installation treating a combined sewer overflow (CSO) at Bornem, Flanders is built. The construction comprises a presettler
and a plug flow treatment zone with floating vegetation elements. The installation is aimed to treat efficiently a so-called two-year
overflow event of 2,309 m³ volume and 0.17 m³/s peak flow. During the past three years a number of overflow events were
registered. Initially the system performed well, with an observed COD-removal efficiency of 68% and an SS-removal efficiency of 95%.
Even nutrient removal took place with values of 37% and 61% for N and P respectively. There was also a becoming “natural”
(presence of plankton and day/night respiration regimes) of the water. Over the years a decrease in performance was noticeable.
During some events more was discharged then brought into the system. This was especially the case for N. It has to be noted though
that the most stringent standards for the discharge of treated wastewater in Flanders were almost never exceeded. Overall the
current discharge of the overflow treatment is a significant improvement, but maintenance is necessary to keep the system
performing well. The applicability of the evaluated system is mainly the treatment of CSO’s causing significant ecological damage.
Identification of ecological flow for benthos community in urban stream. J. Caletkova; D. Kominkova*; J. Nábelková+
Presented by Jana Nabelkova, Czech Technical University in Prague, Czech Republic
The adoption of the Directive 2000/60/EC leads to definition of ecological flow in watercourses which enable organisms or their life
stages fixed on water good life conditions. Significant problems are connected with small urban streams impacted by outlets from
storm sewer systems. The system of watercourses and their flood plain in urban area lost their natural capability to retain big
amount of water and slow down run off. Frequent outflows from sewer and flow variation in the creek put a high demand not only on
the watercourse but also on the aquatic biota. One possibility, how to include biological, hydraulic and morphological parameters in
the complex assessment of the watercourse is IFIM - Instream Flow Incremental Methodology, which defines ecologically acceptable
flows in the watercourse and propose their optimal exploitation. Important instrument of IFIM methodology is the computational tool
Physical HAbitat SIMulation system (PHABSIM) used particularly for the modeling and prognoses of changes in a physical habitat
depending on flow variation with regard to macrozoobenthos species and their life stage. This paper presents range of ecological
flows and suitable microhabitat parameters for macrozoobenthos community in small urban creeks affected by urban drainage.
Experimental analysis of the Hydrass flushing gate and laboratory validation of flush propagation modelling. A. Campisano; E.
Creaco*+; C. Modica
Presented by Enrico Creaco, Università di Catania, Italy
Periodical cleansing operations result necessary inside sewer systems in order to reduce the hydraulic and environmental problems
due to the accumulation of deposits on the bottom of channels. For this objective, new effective hydraulic devices based on the
scouring effects of flushing waves have been recently set-up and adopted in many sewer systems. In this paper, the results of an
experimental and numerical investigation on the hydraulic operation of the Hydrass flushing gate are reported. The experimental
analysis has been carried out using a laboratory channel and a reduced scale model of the gate, in order to characterise the flushing
waves generated by the device. The numerical analysis has been performed using a mathematical model specifically developed for
the simulation of flushing waves inside sewer channels. The comparison of numerical results and experimental data has allowed to
evaluate the applicability under unsteady flow conditions of the outflow relations determined for the Hydrass gate in a previous
investigation under steady flow conditions.
A dimensionless approach for determining the scouring performances of flushing waves in sewer channels. A. Campisano+; E.
Creaco*; C. Modica
Presented by Alberto Campisano, University of Catania, Italy
In the management of sewer systems great attention has recently been addressed to the problems determined by the accumulation
of sediments on the bottom of the channels. The hydraulic flushing devices have proved to be a cost-effective solution for the
channel cleansing and therefore they have been adopted in several sewer networks. This paper reports the results of a numerical
investigation on the scouring performances of flushing waves. For the investigation, a numerical model based on the De Saint VenantExner equations in dimensionless form has been adopted and validated using data derived from laboratory experiments. Then,
simulations have been carried out considering different values of the dimensionless parameters involved in the analysis, in order to
derive indications on the design, set-up and positioning of flushing devices in sewer channels.
Issues concerning the management of greywater in the non-sewered, sub-economic settlements of the Western Cape, South
Africa. K. J. Carden; N.P. Armitage*+; O. Sichone; K. Winter; U.K. Rivett
Presented by Neil Armitage, University of Cape Town, South Africa
The Water Research Commission of South Africa (WRC) has identified greywater as a key area of research in South Africa owing to
the fact that service delivery in sub-economic areas largely consists of on-site dry sanitation with communal water points where
greywater has the potential to create a host of environmental and health problems. It is vitally important therefore that greywater is
properly managed, both to eliminate inappropriate disposal, as well as possibly providing benefits to some communities through
controlled reuse. This particular project aims to understand future challenges with respect to greywater management and includes a
major socio-anthropological component because the key to successful management appears to lie with the attitudes of communities
towards the greywater problem. A comprehensive study has therefore commenced with surveys of sub-economic settlements in the
Western Cape and some preliminary findings have been made. There are two main outputs envisaged for the project; one at a macro
level oriented towards Government, and one at a micro level, aimed at the communities themselves. The Government needs
information regarding typical greywater generation rates for the sub-economic areas and the likely impact of changes in the service
levels associated with water and sanitation services. Communities, municipal planners and policy makers need guidance in the
strategic management and possible reuse of greywater so as to reduce any negative impacts.
Characterization of transitional waters in the context of the WFD - Case studies of Portuguese estuaries. M. Cardoso da Silva*+;
V. Flôxo
Presented by Margarida Cardoso da Silva, LNEC, Portugal
In the European Union (EU) a first demanding Directive, associated with wastewater drainage and disposal was the 91/271/CEE
concerning Urban Wastewater Treatment that imposes particular requirements when the receiving water bodies are estuaries.
Further requirements were introduced by the Directive establishing a framework for Community action in the field of water policy
(2000/60/EC) the Water Framework Directive (WFD). For the implementation of the EU legislation it is of key importance to develop
a comprehensive methodology for the characterization of the pressures on water bodies and of their status. The method to compute
the normalised indicators from the observations is described and tested, requiring the definition of assessment criteria and of an
algorithm to transform the observed values, integrated in time and in space, into dimensionless values and, later, in the normalized
indicators. The test was performed in three Portuguese estuaries, Tejo, Sado and Guadiana, with different characteristic and
pressures. The issues of oxygenation and eutrophication were selected. Although the available data was not collected for the
application of the methodology, it was still possible to define environmental quality classes for each system.
Technical performance assessment of Inflow effects: experimental urban sewer system in Portugal. M.A. Cardoso*; M.C.
Almeida+; C. David
Presented by Maria do Céu Almeida, LNEC-DHA-NES, Portugal
In separate domestic sewer systems the excess of wastewater volumes in wastewater treatment plants can be due to infiltration into
the sewer system from the groundwater, or due to storm water inflows coming from cross connections of storm drains, connected
impervious areas and leaking manholes covers. In general, the effects of inflow/infiltration (I/I) are relatively obvious but usually
there is no objective information on its quantification, origin and economic impact. The location and detection of cross connections
in selected areas together with the technical performance assessment of the system can support the establishment of intervention
priorities. If done extensively, without selection of the most affected areas, this procedure can be time consuming and expensive,
especially for large sewer systems without clear benefits. However, if integrated in the planning of O&M interventions it can be a
means of updating system information and correcting the malfunctions of the sewer system and improve its performance. In this
paper a study on I/I in an experimental urban catchment of 4.5 ha, near Lisbon, in Portugal is presented. The main objectives of the
work were to evaluate and quantify I/I effects on the system performance and to identify the number and location of cross
connections as a first step to define a broader methodology.
Performance indicators for rehabilitation end-users field testing results. M.A. Cardoso*+; R. Matos, I. Pinheiro, M.C. Almeida
Presented by Adriana Cardoso, LNEC, Portugal
CARE-S - Computer Aided Rehabilitation of Sewer Networks is a project funded by the 5th EU Framework Programme. The project
goal is to establish a rational framework for decision-making support on sewer network rehabilitation. CARE-S aims to develop an
integrated and systematic methodology for rehabilitation. The final aim is to contribute to improve the structural and functional
reliability of the sewer networks. The main deliverable will be a Decision Support System (CARE-S prototype) to assist municipal
engineers to establish and maintain effective management of their sewer networks: rehabilitate the right sewer at the right time by
using the right rehabilitation technique at a minimum total cost, before serious failures occur (pro-active approach). The
construction of a control panel of performance indicators (PIs) for rehabilitation is a component of the project aiming at: defining an
appropriate set of rehabilitation performance indicators, developing a software for easier PI assessment and field-testing with
project end-users and defining a sub-set of “predictable” PIs for strategic long term rehabilitation planning. This paper presents the
main features of the software for PI assessment as well as the results of the field-testing, by the end-users involved in the project.
Assessing the impact of infiltration and exfiltration in sewer systems using performance indicators: case studies of the APUSS
project. M.A. Cardoso*+; V. Prigiobbe; M. Giulianelli; E. Baer; J. De Bénédittis; S.T. Coelho
Presented by Adriana Cardoso, LNEC, Portugal
The structural quality and functional efficiency of sewer systems are key parameters to guarantee the transfer of domestic,
commercial and industrial wastewater to treatment plants without infiltration nor exfiltration. Infiltration of groundwater is
particularly detrimental to treatment plant efficiency, while exfiltration of wastewater can lead to groundwater contamination. The
APUSS project associating universities, SMEs and municipalities in 7 European countries, developed new methods and techniques to
assess and quantify infiltration and exfiltration (I/E) in sewer systems. This paper describes the establishment of a set of
performance indicators (PI) developed to assess the impact of I/E on sewer systems and their application to three project case
studies, in Italy and France, focusing on sewer systems characteristics, I/E measurements campaigns and PI application results. The
methodology for PI definition consists in the selection and development of a sewer network property or state variable, which is
expressive of aspects being scrutinized (I/E); the PI values are then calculated; finally, a classification of the PI values is made in
relation to good or bad performance. The use of PI allows a standardized and objective comparison of the performance of sewer
systems and constitutes a means to technically support the establishment of priorities for rehabilitation and/or construction
investments taking into account I/E impacts.
Can we put the PUBLIC back into UTILITIES. A. Cashman*+
Presented by Adrian Cashman, Pennine Water Group, University of Sheffield, United Kingdom (Great Britain)
Since the later half of the 1990’s there has been a growing concern to define the role and rights of the public vis-à-vis access to and
provision of water services. Implicated in this debate has been the question of the nature and extent of stakeholder involvement and
public participation. The purpose of this paper is to explore the relationship between civil society and industry with respect to the
management of water resources and services in the light of the re-representation of water as an economic good. In doing so it
reconfigured the relationship between those that provided the service, its oversight and those that received the service, locating the
relationships in the market and manifest through market relationships. However, there appears to be increasing importance
attributed to participation but it is uncertain how far and in what forms public participation and civil society might reach into policy,
management and practices. The paper examines some emerging examples of public participation and stakeholder involvement from
Europe before considering the implications for water service providers.
Removal of bacterial indicators of fecal contamination in urban stormwater using a natural riparian buffer. M. Casteel*+; G.
Bartow; S. R. Taylor; P. Sweetland
Presented by Michael Casteel, San Francisco Public Utilities Commission, United States of America
Little information is available on the ability of naturally-occurring riparian buffers to remove waterborne microbes from urban
stormwater runoff. In the present study, bacterial indicators of fecal contamination were quantified in stormwater before and after
intentional diversion to a natural riparian buffer (RB) adjacent to a lake located in the City of San Francisco, California. Analysis of
lake water showed that levels of Escherichia coli and total coliforms increased significantly during storm events, indicating the
presence of nonpoint sources of fecal contamination in the area surrounding the lake. When 0.44 million L (5,700 L/min) of
stormwater was intentionally diverted and discharged to the RB, lake levels of E. coli, enterococci, and total coliforms were about 23 log10 (99-99.9%) lower than levels in stormwater. The RB was less effective in reducing bacterial levels during some major storms
(>4 cm precipitation in <48 h) with higher inputs (several million L), but large amounts of uncontrolled surface runoff had been
observed entering the RB and Lake Merced during those events. These results suggest that the RB evaluated in this study worked
effectively to reduce the numbers of bacteria in stormwater from entering a body of water in an urban setting.
Design and RTC of tanks for the control of pollution due to CSOs. C.A. Cenacci; M. Maglionico*+
Presented by Marco Maglionico, Bologna University, Italy
One of the most effectiveness solution for the control of pollution in river caused by combined sewer overflows (CSOs) is to introduce
storages in sewer system in order to retain a part of the storm waters. This paper refers about the analysis of quali-quantitative
control of emissions from overflows by means of tanks designed using historical rainfall series and genetic algorithms. The tanks are
also equipped with mobile gates, real time controlled with a fuzzy logic approach. The work can be summarized in three phases. The
first, consisted of defining the problem and, in particular, the set of rules applied to the control. In the second the system was
17
subjected to a historical rainfall series and assessed by means of an appropriate objective function. A genetic algorithm was used to
define the most appropriate management logic and the minimum volume to assign to the tanks. In the third phase, of validation, the
optimized model was checked on the basis of another historical rainfall series. This work is characterized by a real time control
based, not only on water level, but also on pollutants concentration. The results lead to tanks with a mean volume of about 30
m3/haimp for the virtual sewer network analyzed.
The GIS-based decision support system for urban flooding emergency response. A. S. Chen*+; M. H. Hsu; C. J. Huang; W. Y. Lien
Presented by Albert Chen, National Sci.&Tech. Center for Disaster Reduction, Taiwan, Province of China
The study develops a GIS-based decision support system for emergency responses during floods. The system collects the near-realtime rainfall observation records to determine the flood-prone areas. The information increases the responding time for emergency
managers to take adapted measures. The residents in the high inundation potential areas are warned and evacuated to shelters
before disasters. The application strengthens the preparedness for mitigating the damages caused by floods.The study develops a
GIS-based decision support system for emergency response during floods. The system collects the near-real-time rainfall observation
records to determine the flood-prone areas. The information increases the response time for emergency managers to take adaptive
measures. The residents in areas of high flood potential areas are warned and evacuated to shelters before disasters occur. The
application strengthens the preparation for mitigating the damage caused by floods.
Effective utilization of sewage facilities and unutilized energy in cold regions. Y. Chiba*+
Presented by Yasuto Chiba, Tokyo engineering consultant co.,ltd, Japan
To improve the living environment and water quality of public bodies of water, and to reduce public works expenditures in cold
regions, a snow removal project is proposed. In this project, snow is melted by utilizing the already-installed sewage facilities, and
the facilities designated by the “combined sewer system improvement plan," using the heat that wastewater contains. Possible
effects which can be expected by accelerating snow melting, such as alleviating the severe living conditions in winter and
revitalizing the hollowed urban area, are also discussed. The quantitative evaluations of the findings of the experiments conducted
in Sakata and other cities show advantageous effects, including a reduction of suspended solids (SS) in effluents flowing into public
bodies of water, lower municipal costs for snow removal, and reduced snow removal workload. These results attest to the
effectiveness of utilizing the sewage system to improve urban environments during the snow season.
A field observatory in urban drainage: the OTHU project – a five year experience. B. Chocat*+; L. Bacot; S. Barraud; P. Breil; F.
Malard; J.C. Varnier; T. Winiarski
Presented by Bernard Chocat, INSA, France
OTHU is an on-site observatory that aims to study the different processes encountered all along the urban water cycle associated
with urban drainage. The OTHU project is also a research organisation comprising fifteen research laboratories working in a wide
range of complementary fields including geography, climatology, hydrology, soil mechanic, soil science, hydraulic, chemistry,
biology, social sciences, and economy. The research project is based on data acquisition from 5 sites where continuous monitoring of
climatic parameters, water flows and pollution is carried out in different compartments from the catchment, to the receiving water
bodies. The observatory has been operated for 5 years and many data are now available. This paper describes the observatory itself
and gives some examples of research results and findings.
To prevent floods in Bangkok: An operational radar and RTC application - Rainfall forecasting. S. Chumchean*+; T. Einfalt; P.
Vibulsirikul; O. Mark
Presented by Siriluk Chumchean, Mahanakorn University of Technology, Thailand
Bangkok is known as one of the cities with a high flooding risk because of several reasons. These include: the city’s rapid
urbanization, the Chao Praya river inflow from the north of Thailand, an inadequate drainage capacity, backwater from the tidal
effects of the Gulf of Thailand, and increase of groundwater consumption causing more land subsidence and sub-sequent reduced
drainage capacity. Bangkok Municipal Administration has called for a flood forecasting system integrating information from rain
gauges, hydrometric stations, radar measurements, satellite measurements and numerical weather prediction results. In this
framework, a system based on MIKE FLOODWATCH in connection with SCOUT rainfall processing software has been implemented. The
performance criteria for the flood forecast system are set to be an accuray of 60% on the forecasted accumulated rain with a 3 hour
horizon and a prediction of the water levels within a 5 cm accuracy. Rainfall forecast is an important part of the flood forecasting.
The flood forecasting system will only be successful in providing vital early warning if rainfall forecast inputs are sufficiently
accurate and definitive. This paper presents a procedure to improve the radar rainfall estimation system so that it is capable of
quantitative rainfall estimation and to develop an end-to-end rainfall forecasting system in Bangkok. The SCOUT rainfall forecasting
software was used for forecasting rainfall over the period 1 to 3 hours ahead. The average rainfall forecast accuracy of the 3-hour
forecast lead time of the 14 studied events was found to be 72% according to the selected criterion. Catchment or areal aggregation
was generated automatically from the model and displayed as time series. This quantitative output could thus be directly input to
the flood forecasting model.
Hydrological and hydraulic studies to analyse the main drainage system of the valley of Mexico. H. L. Cisneros-Iturbe*+; R.
Domínguez-Mora
Presented by H. Leonardo Cisneros-Iturbe, Instituto de Ingeniería. UNAM, Mexico
The present work deals with the mathematical simulations of the main drainage system of Mexico City, which serves an urban area of
20 million people on a surface of about 2500 km2. This system is composed by retention dams, surface channels, deep and semi-deep
tunnels, pumping stations and retention lakes. Due to the aquifer’s overexploitation and, its consequents, soil sink problems, the
surface drainage channels have significantly diminished their conducting capacity. This has result in a surcharged operation mode of
the deep tunnels in order to drain the increased volumes of water to those established in their original design. A set of proposed
modifications to the system was studied using the available data (rain statistics, urban wastewater volumes, etc.) and applying the
MOUSE model that simulates the flood routing. This model was fed with incoming hydrographs obtained with a hydrological model
VASOS built out for the valley of Mexico. The simulation results were validated using actual flow and elevation measurements.
Filtration for metals removal from stormwater. S. Clark*; P. Johnson+; R. Pitt; S. Gill; M. Pratap
Presented by Pauline Johnson, The University of Alabama, United States of America
Filtration as a method of stormwater treatment was investigated in a 3-year study. Equilibrium and kinetic studies of metals’ capture
were performed initially on twelve media. The three best performing media: peat-sand mix, compost, and zeolite were then
selected for in-depth study. Upflow filters did not clog as easily as downflow, and longer-term performance was better in the upflow
column. Metals were retained on the filters during anaerobiosis. Metal retention by the filters was not different from what was
observed in oxygenated environments. Tests also indicated that the heavy metals of concern remain strongly bound to the
particulates during long exposures at the extreme pH conditions likely to occur in receiving water sediments. Several media were
tested in a pilot-scale device using water from a detention pond that drains a medium-density residential area. In this series of tests,
the metals concentrations in the influent were extremely low (near the detection limit of the analysis). When the influent metals
concentration was higher, such as shortly after a rain storm, the filters proved effective at removing influent concentrations down to
a level of approximately 10 – 15 µg/L. Removals to concentrations lower than that were not possible on a consistent basis.
Wet-weather pollution from commonly-used building materials. S. Clark*+; M. M. Lalor; R. Pitt; R. Field
Presented by Shirley Clark, Penn State Harrisburg, United States of America
Development in sensitive watersheds continues to pose environmental problems for receiving waters. One contributor to the longterm pollution of sensitive waterways is building and construction materials. However, the long-term effect of many building
materials on the environment has not been quantified. Prior testing of these materials in the laboratory has indicated that the
potential for release (primarily nutrients, lighter hydrocarbons, pesticides, and metals) is significant. Additional testing for metals’
release from aged roofing panels also has shown that the potential for pollutant release still exists after 60 years of exposure to the
environment. The data that is missing from a complete evaluation of specific building materials is behavior over the lifespan of the
material, including the critical period of initial exposure. This paper provides an overview of the limited literature available on the
subject, results from laboratory testing of common building materials and aged roofing panels, and an overview of the next phase of
needed research. Ongoing work at campuses in two rainfall/climate zones in the U.S. have been designed fill in the data gap.
10 years experience of integrated wastewater management & planning in the United Kingdom. I.T. Clifforde*+; R.W. Crabtree
Presented by Ian Clifforde, Black & Veatch Consulting, United Kingdom (Great Britain)
Historically, there have been numerous environmental problems in the UK associated with combined sewer overflow (CSO) and other
wet weather discharges from urban wastewater systems. There were estimated to be around 25,000 CSOs in England and Wales at
the beginning of the 1990s and some 8,000 were believed to be causing pollution problems. A national research programme was
undertaken by the water industry between 1980 and 1994 to address the planning needs for the wet weather performance of urban
wastewater systems. This research culminated in the publication of the Urban Pollution Management (UPM) Manual in 1994. This has
been accepted in the UK as best practice for the investigation of urban wastewater system performance and the development of
cost-effective solutions to environmental requirements for the last 10 years. After decades of relative inactivity prior to privatization
of the UK water industry, CSO improvement has progressively gained in priority. Hence, by 2005 the majority of unsatisfactory CSOs
have been improved. The paper considers how UPM was used to help achieve the requirements of environmental legislation and
public expectation over the latter stages of this period. The paper also looks ahead to developments that may occur in this field in
the years ahead.
Pollutants in highway runoff. B. Crabtree*+; F. Moy; M. Whitehead
Presented by Bob Crabtree, WRc plc, United Kingdom (Great Britain)
In response to rainfall, highway surface runoff discharges may contain pollutants that have accumulated on the carriageway,
particularly following periods of dry weather. In the UK the Highways Agency, in association with the Environment Agency,
commissioned a 5-year study in 1997 to collect data to improve the understanding of contaminants in highway runoff and the
treatment efficiency of drainage systems. The study involved the instrumentation and monitoring of non-urban highway surface
water drainage and the receiving water at 6 sites for a minimum of 1 year. Highway runoff and receiving water samples were
analysed for up to 40 determinands. The results have been used to identify ranges of pollutant concentrations in highway runoff;
relationships between runoff concentrations/loads and both highway and environmental factors; drainage system treatment
efficiencies; and, impacts on receiving waters. The greatest observed pollution removal efficiency was produced by a combination of
a bypass oil separator and surface flow wetland-wet pond. The paper describes the methods used for runoff monitoring and the
results from the initial study at 6 sites, focusing on the efficiency of a number of drainage system types and drainage features.
Assessment of treatment efficiency indicates that there is a wide range of pollution removal efficiencies for the individual and
combinations of treatment devices at the monitored sites.
The effectiveness of selected microbial and chemical indicators to detect sewer leakage impacts on urban groundwater quality.
A. Cronin*+; J. Rueedi; B. Morris
Presented by Aidan Cronin, University of Surrey, United Kingdom (Great Britain)
Sewer and stormwater pipe leakage can lead to the degradation of urban groundwater quality. This groundwater may be
subsequently used for public water supply and so the resulting water treatment and public health consequences can be serious. To
understand the impact of sewer exfiltration on groundwater quality, suitable indicators need to be sampled and analysed for. This
study examined potential sewer-derived inorganic and microbial parameters in the UK city of Doncaster. Sulphite reducing clostridia,
faecal streptococci and boron were all detected in groundwater with reductions compared with sewer values ranging from 1 to 6
orders of magnitude for the former two to 1 to 2 orders of magnitude decrease for boron. The correlation between these two
different indicator types suggests that groundwater quality is being adversely affected by sewer leakage in the study area. The
employment of several and varied indicators can better demonstrate the effect than use of single parameters.
"Dealing with our own sewage" - A community decision making process for developing sewage management strategies. P.
Cuming; E. Bragg; G. Mashiah*+; D. Morrison; J. Spencer
Presented by Greg Mashiah, Clarence Valley Council, Australia
‘Dealing With Our Own Sewage’ (DWOOS) is an innovative model for community participation and decision-making created and
refined through the process of developing sewage management strategies in New South Wales, Australia. The DWOOS process
comprises three key components: Community Consultative Committee and Participation Process; Communication Strategy and
Skilling Processes including Creative Media, Consultants Brief for Investigation of Management Options and Consultant's Report; and
Options Evaluation Kit and Decision-Making Process. The power and ongoing success of this process lies in the fact that it deals with
community and interpersonal issues, in conjunction with the specific technical issues concerning sewage management per se. It is
based on cooperatively identifying and dealing with environmental, social, economic and technical issues in a comprehensive and
integrated manner. Although the DWOOS model was developed to deal with sewage management issues, it has far wider application
for resource and major service infrastructure projects.
The influence of extensive vegetated roofs on runoff water pollution loads. J. Czemiel Berndtsson*+; L. Bengtsson
Presented by Justyna Czemiel Berndtsson, Lund University, Sweden
The influence of extensive sedum-moss vegetated roofs on runoff water pollution loads was studied for four full scale installations
located in southern Sweden. The aim of the study was to ascertain whether the vegetated roof behaves as a sink or a source of
pollutants on annual basis. The pollution loads from vegetated roofs was also compared with the pollution loads from two nonvegetated roofs located in the study areas. The annual pollution loads were calculated based on the measured water quality and the
volumes of annual precipitation and the annual roof runoff. Concentrations were measured during four precipitation events in
November-December 2003. The following metals and nutrients were investigated: Cd, Cr, Cu, Fe, K, Mn, Pb, Zn, NO3-N, Tot-N, PO4P, and Tot-P. The results show that, on the annual basis when total loads are considered, vegetated roofs behave as sink of nitrogen
and source of potassium and phosphorus, the last with the exception of the oldest vegetated roof. The influence of vegetated roofs
on annual heavy metals loads in runoff is less significant.
19
Developing and expanding the research community for SUDS. J. Davies*+; R. Wade; C. Jefferies; C. J. Pratt
Presented by John Davies, Coventry University, United Kingdom (Great Britain)
This paper covers the creation and experience to date of the UK-based Engineering and Physical Sciences Research Council (EPSRC)
research network for sustainable urban drainage systems, ‘SUDSnet’. The paper traces the evolution of UK research in SUDS and the
development of the community of researchers and practitioners that has supported it. The network provides a focus for a
geographically dispersed and rapidly expanding research community within the UK. It encourages cooperation between researchers
and practitioners who can provide vital feedback from their own experiences. This cooperation adds value to current research work
and informs best practice and understanding amongst industry partners. Within the UK, implementation of SUDS on the ground has
been at a faster pace in Scotland than in England and Wales and therefore there has been some separation in the development of the
research communities. SUDSnet is based in two established research centres, one in Scotland at the University of Abertay Dundee,
and one in England at Coventry University. The paper describes the aims of SUDSnet and achievements so far.
Transitions to more sustainable concepts of urban water management and water supply. R.E. de Graaf+; F.H.M. van de Ven*
Presented by Rutger De Graaf, Delft University of Technology, Netherlands
The sustainability of the existing urban water management systems in the Netherlands can be improved significantly. This paper
deals with investigating the feasibility of other concepts for drainage and water supply, in order to achieve more sustainable urban
water systems in the future. To start with, a number of features of the urban water system and water supply, which can be regarded
as unsustainable, will be evaluated. Secondly, the feasibility of a potential future water system concept, ’the closed city’, is
discussed. The closed city uses local rainfall as the only source of water; no external water supply is needed for such a city. By
means of a ‘connected reservoir model’ water availability is evaluated for various climatic situations. Water quality is discussed,
using pollution sources, balance principles and requirements of the water system as starting points to reach the Maximum Allowable
Risk standards for oxygen concentration. Finally, guidelines for the design of ‘closed cities’ are presented, illustrating (1) the
consequences of the new concept and (2) the transitions required to implement such a new concept.
On the effect of spatial variances of historical rainfall time series to CSO performance evaluation. S. De Toffol*+; Y. De Simon
Bürstrom; W. Rauch
Presented by Sara De Toffol, University of Innsbruck, Austria
Historical, high-resolution rain series are the backbone of modern combined sewer overflow (CSO) structure design. These rain series
are the input to the computational estimation of the performance of the measures with respect to CSO pollution abatement.
However, only at few locations those historical precipitation measurements are available. Frequently rain series have to be used
from gauging stations at a significant distance. In order to judge on and to compensate for this influence an estimate between rain
characteristics and CSO performance indicators would be useful. In this paper such correlations have been sought for a collection of
37 rain series covering large areas of Europe. It was found that the mean annual rain volume can explain most of the variances for
the performance indicators Number of overflows and CSO volume. For explaining the spatial differences in the efficiency of the CSO
structure another rain characteristic, i.e. the maximum event with a return period of one year, is to be used.
Living Infrastructure - The Integration of Natural Drainage in the Urban Environment. P. Dedyo*+; P. Staeheli; T. von Schrader; K.
Gwylim
Presented by Paul Dedyo, SvR Design Company, United States of America
Cities across the United States are reversing the historical trend toward urban sprawl by encouraging more densely developed,
mixed-use communities. These efforts provide protection for rural and natural areas, but strain existing urban infrastructure. As a
result of denser developments and the resulting increase of impervious roofs and pavements under traditional construction practices,
jurisdictions must increase their storm drainage capacities, which is a costly solution. Many are looking to sustainable approaches
using natural systems to help slow the stormwater flows while providing a means of cleaning the water. These natural systems can
provide a more flexible infrastructure of conveyance and treatment while adding an aesthetic to the community. Sustainable
approaches however, often involve unconventional designs requiring variances to current standards. As a result, project proponents
have the added responsibility of convincing the permitting agency that the design will meet the intent of Code requirements. It has
taken dedication from sustainable design pioneers at the local level to push through the first projects. As more projects incorporate
sustainable technologies, there will be more opportunities to educate the public and monitor their long-term performance and
benefits. In time there will be a familiarity with these innovative sustainable design components of today to become our codes and
standards of tomorrow.
Capturing extreme rainfall events in Kerayong catchment. M.N.M. Desa*+; M. Akhmal H.; A.W. Kamsiah
Presented by Mohamed Nor Mohamed Desa, Humid Tropics Centre Kuala Lumpur, Malaysia
This paper will discuss the extreme event of recorded rainfall in the Kerayong river catchment which has been categorised as suburban catchment with rapid growth rate due to urbanisation process. From the two years data collected in the catchment, the
analysis will determine the number of storm events, distribution of rainfall in the catchment and the highest rainfall at 1,3 and 5minutes interval for better understanding and input to flood forecasting and flood mitigation procedure in the future for similar
catchment characteristics.
Behavior of the activated storage-volume of flushing waves on cleaning performance. J. Dettmar*+; P. Staufer
Presented by Joachim Dettmar, RWTH Aachen (ISA), Germany
Deposits build up in sewer networks during both dry-weather and storm-water events. Especially in combined sewers, the sediment
materials cause various undesirable effects. Flushing devices are able to remove deposits in sewers by generating flushing waves. To
optimize the flushing with so called Storage-Volume-Activated-Devices (SVAD) numerical studies were carried out. The objective was
to investigate the behaviour of the activated storage-volume of flushing waves on cleaning performance.
From single-objective to multiple-objective multiple-rainfall events automatic calibration of urban storm water runoff models
using genetic algorithms. F. di Pierro*+; S.-T. Khu; D. Savic
Presented by Francesco di Pierro, University of Exeter, United Kingdom (Great Britain)
The calibration of storm water runoff models is a complex task. Early attempts focused on the choice of a performance criterion
function that could capture all the facets of the problem into a Single-Objective framework. Subsequently, the awareness that a
good calibration must necessarily take into account conflicting objectives led to the adoption of more sophisticated Multi-Objective
approaches. Only recently, the focus has shifted towards effective ways of exploiting the mounting information provided by the
availability of many set of concurrent rainfall and flow measurements. This paper revisits through a case study the transition just
elucidated: the calibration of a SWMM model applied to a catchment in Singapore is tackled through a Single-Objective, a MultiObjective and a Multi-Objective Multiple-Event (MOME) paradigm respectively. A new approach to support the latter is presented
herein. It consists in formulating the problem of model calibration as a Multi-Objective problem with m x r objective functions,
where m and r are the number of performance criteria and rainfall events respectively, that must be optimized simultaneously.
Results suggest that the new MOME framework performs significantly better than the others tested on the case study presented.
Development and investigation of a pollution control pit for treatment of stormwater from metal roofs and traffic areas. C.
Dierkes*+; P. Göbel; M. Lohmann; W.G. Coldewey
Presented by Carsten Dierkes, HydroCon GmbH, Germany
Source control by on-site retention and infiltration of stormwater is a sustainable and proven alternative to classical drainage
methods. Unfortunately sedimentary particles and pollutants from drained surfaces cause clogging and endanger soil and
groundwater during long-term operation of infiltration devices. German water authorities recommend the use of infiltration devices
such as swales or swale-trench-systems. Direct infiltration by underground facilities such as pipes, trenches or sinks without pretreatment of runoff is generally not permitted. Problems occur with runoff from metal roofs, traffic areas and industrial sites.
However, due to site limitations, underground systems are often the only feasible option. To overcome this situation, a pollution
control pit was developed with a hydrodynamic separator and a multi-stage filter made of coated porous concrete. The system treats
runoff at source and protects soil, groundwater and receiving waterways. Typically, more than 90 % of the pollutants such as
sedimentary particles, hydrocarbons and heavy metals can be removed. Filters have been developed to treat even higher polluted
stormwater loads from metal roofs and industrial sites. The treatment process is based on sedimentation, filtration, adsorption and
chemical precipitation. Sediments are trapped in a special chamber within the pit and can be removed easily. Other pollutants are
captured in the concrete filter upstream of the sediment separator chamber. Filters can be easily replaced.
Pollution retention of different permeable pavements with reservoir structure at high hydraulic loads. C. Dierkes*+; M.
Lohmann; M. Becker; U. Raasch
Presented by Carsten Dierkes, HydroCon GmbH, Germany
Permeable pavements for sustainable stormwater management and source control are have been furthered and investigated in
Germany for many years. In particular the runoff from streets and parking areas with low traffic densities can be permitted to
infiltrate with the aid of concrete pavers with wide joints. But runoff from traffic areas contains pollutants such as heavy metals and
hydrocarbons that can endanger the soil and groundwater. Furthermore solids in stormwater runoff bring about clogging. Since
clogging is a well known problem, it is not clear how long permeable pavements provide sufficient infiltration capacity and which
factors must be considered at planning and construction if a long service life of the systems is to be ensured. Investigations on the
hydraulic behaviour and the pollutant transport were carried out on a car park of a sports facility. Parts of the traditional pavement
of the car park were reconstructed with trenches covered with permeable pavers. The ratio of impermeable to permeable area is
16:1. The infiltration capacities of the pavers after three years of operation and the water quality along the path from rainwater and
runoff to seepage water and groundwater were observed. Additional laboratory rigs were charged with an artificial runoff to
determine the pollution retention capacities of different substrates. It is concluded that the system is not satisfactory in respect of
its hydraulic behaviour but that it works very efficiently in respect of pollution retention.
A critical appraisal of retention pond sizing criteria for water quality treatment. G. Dimova; B. W. Ballard*+; R. Kellagher
Presented by Bridget Woods Ballard, HR Wallingford, United Kingdom (Great Britain)
This paper presents a critical appraisal of sizing criteria for permanent retention pond volumes in the UK, together with
recommendations for a more holistic approach that considers both climatic influences and natural environmental processes. High
frequency rainfall events are generally significantly smaller than the design pond volume (Vt) and thus, for most storms, the
proportion of turnover of the permanent pool will be less than 1. It will therefore be the quality of the permanent pool rather than
the influent that will tend to determine the quality of effluent discharged to receiving waters. The extent of natural physical and
biological processes occurring in the pond are likely to be dependent on the residence time of the water. Water quality of a
treatment train of small, vegetated ponds has been studied at a site in the UK. This study indicates that effluent nutrient
concentrations can show negative relationships with residence time. The water quality shows good correlation with an index of
antecedent wetness and it is suggested that this parameter may be a key influence on the performance of ponds with respect to
nutrient removal. Antecedent wetness and residence time vary significantly with both season and geographical location.
Optimizing Montana’s model to permit urban drainage in humid tropical environment: the case of Abidjan (Côte d’Ivoire). K.
Dongo*+; M. Diamandé; G. Cissé; M. Tanner; J. Biémi
Presented by Kouassi Dongo, University of Cocody / CSRS, Côte D'ivoire (Ivory Coast)
In sub-Saharan Africa, the "hygienic" model used in urban drainage is faced with constraints in humid tropical environment, subjected
to a high level of climatic variability. In Côte d’Ivoire adapting Montana's rain model is not satisfactory for certain time slots (Peuch
and Gonni, 1984) whereas this model includes the Caquot's rate-of-flow model used in urban drainage. This work aims at optimizing
and designing models which best simulate tropical downpours and help in calculations relating to urban drainage in Abidjan and
elsewhere. The methodology based on a probabilistic and stochastic approach used rainfall data covering the period from 1958 to
2000, from the Abidjan Airport Weather Station. The various statistical processing, sustained by Kolmogorov and Cramer fit tests
showed that the rainfall distribution in Abidjan area is in line with Gumbel’s law (10-30mn rainfall) and that of Galton (45-240mn
rainfall). Including the data in mathematical conversion formulas made it possible to optimize the Montana's parameters and to
design a new model which best simulates downpours in Abidjan. In addition, analysis of the Nicholson index reveals a drop in rainfall
in Abidjan with a cyclical evolution (17-year period), alternating dry, normal and wet periods. Waiting for its application to judge its
value, this new model is relevant since it overlaps two very satisfactory models.
The development of a methodology to manage the proactive maintenance of sewerage assets within the context of
serviceability. H. Duncan*+; S. Arthur
Presented by Helen Duncan, Heriot-Watt University, United Kingdom (Great Britain)
In sewerage asset management, there has been a concerted move away from primarily assessing system capacity, to focus on
“serviceability” as a key performance indicator. In the UK, water regulators recognise that the prime concern of customers is
avoiding flooding of their property, as environmental improvements can often be intangible. However, regulators insist that
environmental factors are also given attention. Based on these considerations, it is evident that sewerage providers will increasingly
consider undertaking proactive maintenance on sub-critical and non-critical assets in order to reduce the risk of reduced levels of
serviceability to customers. This paper documents the development of “Failure Mode Effect and Criticality Analysis” (FMECA) as a
tool to manage capital maintenance expenditure within the context of “serviceability” to customers, the public and the
environment. The FMECA model has been applied alongside Infoworks-CS to determine critical points in a small Edinburgh (UK)
coastal catchment. It also discusses how these results are linked to customer complaints held in a GIS database and how the FMECA
approach was able to recommend which assets should be proactively maintained to minimise the risk of serviceability loss. For the
catchment considered, key serviceability performance indicators were found to be CSO spills, flooding in residential areas, flooding
in commercial zones and disruption to traffic.
21
Confined water sensitive urban design (WSUD) stormwater filtration/infiltration systems for Australian conditions. A. Dunphy*+;
S. Beecham; C. Jones; A. Collins; M. Liebman; J. Wells; P. Michael
Presented by Alison Dunphy, University of Technology, Sydney, Australia
This paper describes a project that investigates confined stormwater infiltration/filtration systems and their ability to reduce and
retain pollutants present within stormwater runoff. These highly innovative Water Sensitive Urban Design (WSUD) systems are
located in three locations to the north and south of Sydney, Australia. They are positioned at different geographic locations and face
different subsoil conditions, pollutant loadings and other constraints. The systems contain specially designed porous concrete pipes.
Stormwater exfiltrates through the permeable walls of the pipe into the surrounding substrate media material. This provides
primary, secondary and tertiary treatment of the stormwater. The systems are positioned underground and are designed to ensure
that the integrity of surrounding soil, vegetation, groundwater and receiving water is not negatively impacted. The focus of this
paper is the results obtained from the analysis of stormwater samples collected from the inlet and outlet of the systems. The results
indicate significant reductions in the concentration of pollutants present in the stormwater that passes through the system. Some of
the findings include: approximately 45% reduction in nutrient concentrations, while zinc concentrations have been lowered by
approximately 90% and Faecal Coliform levels have been reduced by approximately 95%. The monitoring work is ongoing and further
sample collections are required to further validate the findings.
Use of computational fluid dynamics to assess the disinfection performance of a combined sewer overflow treatment chamber.
D. Egarr*+; M. G. Faram; I. Guymer; T. O’Doherty; N. Syred
Presented by Darrell Egarr, Cardiff University, United Kingdom (Great Britain)
The fluid residence time characterisation of a 3.4m diameter Hydrodynamic Vortex Separator (HDVS) has been carried out over a
range of flowrates. Computational Fluid Dynamic (CFD) modelling has also been undertaken for the same conditions and validated
against the experimental results, for which reasonable correspondence has been found. Using the results from the CFD modelling and
batch inactivation results from the disinfection of secondary treated wastewater, it is shown that the theoretical performance of a
HDVS as a contact vessel for disinfection can be predicted.
A hydrologists' guide to radar use in various applications. T. Einfalt*+
Presented by Thomas Einfalt, einfalt&hydrotec GbR, Germany
This paper is giving guidance on how to answer the question when and where to use which kind of radar data for a given hydrological
application. In order to approach this goal, several corner stones are developed to provide guidance for hydrologists. Examples for a
successful use of radar data are given. Reasons for the still quite limited routine use of radar data are explained and ways to improve
this situation are shown.
Experimental results of a high rate pilot-scale retention treatment basin for the control of combined sewer owerflow in
Windsor, Canada. A. S. El-Gendy+; V. Roussinova; J.G. Li; N. Biswas*
Presented by Ahmed El-Gendy, Ain-Shams University, Egypt
Pilot plant experiments were carried out to examine the performance of a retention treatment basin (RTB) with chemical
coagulation in the treatment of combined sewer overflow (CSO) for the City of Windsor, Ontario, Canada. The pilot plant was
operated at surface overflow rates (SOR) up to 57 m/h. This study demonstrated that the use of polymer coagulation significantly
improved settling characteristics of solids, and allowed the SOR in the RTB to be increased significantly. The effluent quality met the
new Ministry of Environment Ontario (MOE) Procedure F-5-5 in terms of BOD and SS removal. The flushing box was adequate in
removing the retained Floatables and solids from the RTB.
The DayWater decision support approach to the selection of sustainable drainage systems: A multi-criteria methodology for BMP
decision makers. J. B. Ellis*+; J. C. Deutsch; M. Legret; C.Martin; D. M. Revitt; L. Scholes; H. Seiker; U. Zimmerman
Presented by John Bryan Ellis, Middlesex University, United Kingdom (Great Britain)
The decision-making process for the selection of Best Management Practice (BMP) systems for stormwater runoff management
involves a variety of stakeholders within public and private sectors holding differing powers and opinions regarding the significance
they attribute to differing criteria. The paper describes a web-based multi-criteria analysis (MCA) approach being developed within
the EU 5th Framework DayWater project (www.daywater.org) to support stakeholder negotiation and the development of mutually
acceptable sustainable solutions to the problem of control and treatment of urban surface water drainage. The MCA matrix
methodology is outlined and some of the advantages and limitations of the procedure and its application are discussed.
Mitigation measures towards morphological alterations of rivers: The receiving water as part of the integrated wastewater
system. C. Engelhard*+; S. Achleitner; I. Lek; W. Rauch
Presented by Carolina Engelhard, University of Innsbruck, Austria
Measures in the rivers, their potential to mitigate morphological alterations caused by overflow events of urban drainage structures
and their cost-effectiveness have been investigated. The receiving water is seen as part of the urban wastewater system since
integrated management of the system has to consider measures in the receiving water as an option for improvement of the system.
In this study the measures were evaluated using the software tool REBEKA. It has been found that increase of combined sewer
overflow storage volume is less cost-effective than the investigated in-stream measures. Bed paving with coarse material is an
effective and cheap method to reduce erosion problems. Reduction of slope required the smallest relative changes but has to be
transferred into applicable methods like ‘increase of meandering’. The effectiveness of the methods for reduction of slope as well as
of the measure ‘channel widening’ strongly depends on the dimension of the erosion problem- their applicability is limited for huge
impacts. Evaluation of measures in different sub systems of the wastewater system with simulation tools can reveal interesting
alternatives. Measures in the receiving water can be cost-effective and enhance the ecological quality which is an important aspect
in the implementation of the European Water Framework Directive.
Selection of stormwater priority pollutants. E. Eriksson*+; A. Baun; P. S. Mikkelsen; A. Ledin
Presented by Eva Eriksson, Technical University of Denmark, Denmark
The quality of stormwater mainly depends on the types of surfaces the stormwater encounter (roads, parking lots, roofs etc.). All
types of constituents may cause problems during decentralised treatment, re/use, or detention of stormwater. The objective of the
presented work was to propose a list of selected stormwater priority pollutants (SSPP), which can be used for assessing pollutant
sources & fluxes, the behaviour, fate and toxicity of pollutants during passage through best management practices (BMPs) and the
environmental risk associated with their subsequent dispersal in the environment. The methodology used in this study; Chemical
Hazard Identification and Assessment Tool (CHIAT) aims at selecting the most relevant SSPP and contains five steps; Source
characterisation, Recipient, receptor and criteria identification, Hazard and problem identification, Hazard assessment and Expert
judgement. The SSPP-list identified consists of water quality parameters (BOD, COD, SS, nitrogen, pH and phosphorus); metals
(cadmium, chromium (as chromate), copper, nickel, lead, platinum and zinc); PAHs (naphthalene, pyrene and benzo[a]pyrene);
herbicides (pendimethalin, phenmedipham, glyphosate and terbutylazine); and xenobiotic organic compounds (XOCs) (nonylphenol
ethoxylates, nonylphenol, pentachlorophenol, di(2-ethylhexyl)phthalate, PCB-28 and methyl tert-butyl ether) representing persistent
and ubiquitous compounds as well as compounds deriving from specific anthropogenic sources.
CSO detention tanks in Barcelona: Real time control design and operation. I. Escaler; A. Gil+; R. Guasch*; J. M. Verdejo
Presented by Alicia Gil, CLABSA, Spain
The environmental concern in the sewerage field has led Barcelona to build and operate its first CSO (combined sewer overflow)
detention tank. It has been built in the zone of Forum de les Cultures 2004 and its main objective is the environmental protection of
the new area seafront. This tank will be part of the Remote Control System of Barcelona’s sewer network so its regulation strategy
has been designed. This paper presents the design process of the regulation strategy that operates on the mobile elements of the
tank such as gates and pumping stations. This regulation strategy must be coordinated with the waste water treatment plant (WWTP)
which is the final destination of the water stored in the tank. Special parameters have been taken into account: water permanence
time indicator, redox and DO (Dissolved Oxygen) measurements, which tell about the quality of the water kept in the tank. Taulat
CSO detention tank Automatic Local Regulation demonstrates that integral management of the sewer system, waste water treatment
plant and receiving waters helps to improve bath water quality in the tank’s actuation zone.
Modelling sorption of 3 heavy metals by porous pavements. S. Fach*+; W. F. Geiger
Presented by Stefan Fach, University of Essen, Germany
Due to the implementation of sustainable water management (systems) in Germany more and more infiltration facilities have been
built in the last few years. As the infiltration of rainwater reduces the hydraulic stress and pollution of rivers and lakes by combined
sewer overflows when heavy rainfall occurs, the infiltration of rainwater has been excluded from compulsory sewage disposal by law
in several Federal States. Particularly in the Emscher catchment area – a densely populated area in North Rhine Westphalia – there is
often not enough space for topsoil infiltration facilities and in addition to this, the distance between groundwater table and surface
is often not sufficient for subsoil infiltration facilities. Therefore, the use of permeable pavements as an infiltration measure for
areas with little or no traffic can be an appropriate solution. The infiltration of urban runoff always implies a seepage of substances
into the soil and groundwater at specific entry points. In order to prevent a “shifting of the pollutant problem” from the wastewater
plant and from the receiving water to the soil and groundwater, the long term effect of infiltration was modelled for 50 years of
operation time. The modelling was done for the relevant heavy metals in surface runoffs zinc, copper and lead.
Innovative approaches to urban stormwater management. M.G. Faram*+; R. Y. G. Andoh; C.A. Williams
Presented by Michael Faram, Hydro International, United Kingdom (Great Britain)
‘Engineered’ or ‘hard’ structure based SuDS (Sustainable (Urban) Drainage Systems) have become popular in recent years, presenting
further options to the drainage engineer beyond some of the more conventional approaches. However, as with any approach, correct
design practice must be applied if systems are to be effective and maintainable. Robust management of sediments is a prerequisite
for the successful operation of any drainage system. If not adequately managed, sediments will accumulate in undesirable locations,
making maintenance difficult, and will pass on to receiving watercourses, presenting a pollution threat. The paper considers best
practice in the design and linking together of ‘hard’ SuDS components, specifically storage systems and sediment interceptors. It is
concluded, based on the outputs of recent studies, that an optimal system will incorporate a storage chamber with designed-in
sediment transfer facilities, feeding onward to well-designed flow control and sediment capture facilities.
Using a simple model to predict the behaviour of pollutant loads. M. Francey*+; H.P. Duncan; A. Deletic; T.D. Fletcher
Presented by Matt Francey, Melbourne Water, Australia
This paper presents a simple method for predicting event loads and the behaviour within events of total suspended solids (TSS), total
phosphorus (TP) and total nitrogen (TN) from urban catchments. Four Australian catchments with a variety of sizes and land uses are
examined; three in temperate Melbourne and one in sub-tropical Brisbane. The two-parameter model typically explains 70- 90% of
the variation in event loads at a site, satisfactorily predicts the loading rates within events and is relatively easy to calibrate.
Rainfall intensity over short timesteps is considered to be the main driver of pollutant mobilisation.
Statistical methods towards more efficient infiltration measurements. T. Franz*+; P. Krebs
Presented by Torsten Franz, Dresden University of Technology, Germany
A comprehensive knowledge about the infiltration situation in a catchment is required for operation and maintenance. Due to the
high expenditures an optimisation of necessary measurement campaigns is essential. Methods based on multivariate statistics were
developed to improve the information yield of measurements by identifying appropriate gauge locations. The methods have a high
degree of freedom against data needs. They were successfully tested on real and artificial data. For suitable catchments it is
estimated, that the optimisation potential amounts up to 30 % accuracy improvement compared to non-optimised gauge
distributions. Beside this, a correlation between independent reach parameters and dependent infiltration rates could be identified,
which is not dominated by the groundwater head.
Prediction of sediment transport and filling rates of invert traps in combined sewers. A. Fraser+; A. Schellart; R. Ashley*; S. Tait
Presented by Alasdair Fraser, Ewan Group plc, United Kingdom (Great Britain)
A sediment transport prediction model and an invert trap performance model for combined sewers were linked. The modelling of the
sediment transport was achieved by combining modified existing models of sewer sediment transport, erosion, and deposition. The
invert trap performance model simulated sediment trapping efficiency for traps of a given geometry, for a range of sediment
characteristics at given flow conditions. Two case studies are reported in this paper, one in an existing sewer system in Dundee (UK)
and one for a newly designed sewer in Zurich (Switzerland). The sediment trapping efficiency model developed for Dundee combines
Computational Fluid Dynamics, field observations and existing sediment transport theory. The trapping model developed for Zurich
combines Computational Fluid Dynamics and the results from a physical scale model.
Plant-covered retention soil filters (RSF) Fulda Fellenweg for advanced CSO treatment - a ten year field report. F. Frechen+; W.
Schier*; J. Felmeden
Presented by Franz-Bernd Frechen, University Kassel, Germany
Massive improvement of municipal wastewater treatment during the last 20 years has reduced the pollution load of our water bodies
significantly. At the same time, pollution load resulting from combined sewer overflows (CSO) increased which made appropriate
countermeasures necessary. Up to now, this is usually done by introducing combined wastewater basins in accordance to the German
ATV Standard A128 (ATV, 1992), which deals with design and construction of this type of installations. However, the effect of these
installations is limited, according to their specific size, and especially the reduction of nutrient compounds is not sufficient, as these
installations may include sedimentation as a first treatment process which does not affect the soluble substances at all. The only
technology that is capable of reducing settable compounds as well as soluble compounds is the plant covered retention soil filter
(RSF). First RSFs were built in Germany about 10 years ago at a few sites to treat storm water overflows from combined sewer
systems in order to meet advanced standards. This paper describes one of the first German RSF plants in Fulda (Federal State of
Hessia) and discusses the results of an operation period lasting for more than ten years.
Design and construction of plant-covered retention soil filters (RSF). F. Frechen+; W. Schier*; J. Felmeden
Presented by Franz-Bernd Frechen, University Kassel, Germany
23
Massive improvement of municipal wastewater treatment during the last 20 years has reduced the pollution load of our water bodies
significantly. At the same time, pollution load resulting from combined sewer overflows (CSO) increased which made appropriate
countermeasures necessary. Up to now, this is usually done by introducing combined wastewater basins including sedimentation as a
first treatment process which does not affect the soluble substances at all. The only technology that is capable of reducing settable
compounds as well as soluble compounds is the plant covered retention soil filter (RSF). First full scale RSFs were built in Germany in
the early 90ties within the scope of pilot projects. Today the pollution load caused by CSO becomes predominant in Germany and
therefore RSF technology covering mechanical and biological CSO treatment gets more and more attractive. Thus, appropriate
guidelines have to be elaborated or already existing guidelines have to be updated. The latter is one of the goals of a research
project carried out by the Department of Environmental and Sanitary Engineering (DESE) of the University of Kassel covering building
and operation of three new RSF in the Federal State of Hessia. Upon completion of the RSF building phase this paper summarises the
most important features from the construction site, which easily can be mishandled.
Modelling urban stormwater impact mitigation by using BMPs and storage tanks. G. Freni*+; G. Mannina; G. Viviani
Presented by Gabriele Freni, Università di Palermo, Italy
The continuous growth of urban areas and the increasing public awareness about environmental impact of stormwater raised high
interest on quality impact on the receiving water bodies. Indeed, in the last decades, large efforts have been provided for improving
urban drainage systems in order to mitigate environmental impacts. In the present paper, a simplified modelling approach has been
developed in order to evaluate the mitigation efficiency of different BMP schemes including infiltration and storage facilities and
both considering possible distributed controls and centralised structures. The main goals of the research are the simulation of BMP
efficiency in different operational conditions considering performance reduction due to clogging phenomena and the comparison
between different mitigation measures schemes. For this reason long term simulation has been used in order to take into account
also the effect of sediments in BMP hydraulic capacity reduction. The developed simplified models have been calibrated and applied
to the Parco d’Orlèans experimental catchment (Palermo – Italy). The analysis results allowed for some interesting consideration
about BMP design criteria and the possibility of adopting different BMP techniques in mixed mitigation schemes.
Centralised urban wastewater reuse: What is the public attitude?. E. Friedler*+; O. Lahav
Presented by Eran Friedler, Technion, Israel
Public support is crucial for successful implementation of wastewater reuse projects. This paper analyses the findings of a
questionnaire-type survey (256 participants) conducted to determine the attitude of Israeli urban public towards possible urban
reuse options. The paper summarises the support / objection to 13 reuse options and the correlation between support and
environmental awareness and perceptions. Results show that high proportion of the participants supported options perceived as lowcontact, such as irrigation of public parks (96%), sidewalk landscaping (95%) and use in the construction industry (94%), while highercontact reuse options found lesser support (e.g. commercial launderettes, 60%). No correlation was found between biographical
characteristics and support (education, gender, income, age). Based on the results, public campaigns in Israel should focus on
disseminating information regarding wastewater treatment technologies, discuss health related issues, highlight the positive
economic impact of water reuse and generate a positive public opinion, as these tend to influence individuals to support reuse
projects.
Experience with the implementation of a real-time control strategy for the sewer system of the Vienna city. L. Fuchs*+; T.
Beeneken; G. Pfannenhauser; A. Steinwender
Presented by Lothar Fuchs, Institute for technical and scientific Hydrology, Germany
The development and implementation of a real-time control strategy for the sewer system of the Vienna city was scheduled for
completion in 2004, but the implementation of the first phase was finished in early 2005. The 4.5 years project comprises all
planning and implemen-tation phases. A measuring system including 25 rainfall, 40 flow and 20 water level measurements was implemented to serve for model calibration and real-time control purposes. The detailed network of approx. 53,000 pipes was reduced
to a coarse network of approx. 2,600 pipes. The land use data were derived from aerial photographs. Rainfall runoff simulations
were used to examine the system behavior and to develop the rule base. In a simulated real-time control the rule base was
improved, while further improvements will be done on-line with a self-learning sys-tem. A forecasting model using rainfall radar data
will additionally influence the control deci-sions. The simulated results for the first phase of implementation, demonstrating the
benefits of RTC for the Vienna sewer system are explained. The comparison between measured and simulated real-time control are
not presented in the paper but in the oral presentation. The ex-perience gained from implementation is discussed.
Assessment of uncertainties in the modelling of CSOs. J. C. García-Salas*+; B. Chocat
Presented by Juan Carlos García-Salas, Instituto Mexicano de Tecnología del Agua, Mexico
Engineers generally use simulation tools such as SWMM, MOUSE, HYDROWORKS to simulate the operation of sewer systems. Equations
that are used by these models to represent the hydraulics of sewer systems are well known as well as their performance. Thus the
assessment of the performance needs to suppose that the user is an expert who is able to describe each facility in the most accurate
way according to the model. In Western Europe, important parts of sewer systems are old and combined structures. Such structures
very often include very complicated special structures, especially within CSO facilities. Experience shows that the performance
limits of the models do not rely on the accuracy of the equations, but on the ability of the modeller to properly describe these
special structures. The objective of this research is to assess the part of errors and uncertainties which originates from modellers’
inconsistencies in the description of special structure. Even if the results are obtained with specific software (CANOE), results can
easily be generalised to other models, since the equations used (Barré de Saint Venant) are almost the same.
Spatial variability of PAH load of urban wet weather pollution in combined sewers. J. Gasperi*; R. Moilleron+; G. Chebbo
Presented by Regis Moilleron, CEREVE, France
The OPUR research programme created in Paris an experimental on-site observatory of urban pollutant loads in combined sewer
systems in order to characterise the dry and wet weather flows, at different spatial scales. This article presents the first results on
the spatial variability of the PAH load during wet weather flow (WWF). At the scale of a rain event, investigations revealed that (i)
PAH concentrations were relatively homogenous whatever the spatial scale and were greater than those of the dry weather flow
(DWF); (ii) PAH distributions between dissolved and particulate phases were constant and (iii) PAH fingerprints exhibited a similar
pattern for all catchments. Moreover, an evaluation of the contribution of DWF, runoff and erosion of sewer deposits to WWF load
was established. At the scale of the Marais catchment, the contributions were evaluated at 14, 8 and 78%, respectively. For all the
catchments, runoff contribution was found quite constant and evaluated at about 10%, according to the calculation hypothesis. The
DWF contribution was greater for bigger catchments (>900 ha) when compared to the Marais catchment (42 ha). On the contrary, the
sewer erosion contribution was lower for larger catchment, but still remains an important source of pollution.
On the road to a new stormwater planning approach: from Model A to Model B. G. D. Geldof*+; P. Stahre
Presented by Govert Geldof, Tauw, Netherlands
Traditional models for planning urban water systems are to great extent based on technical and economic considerations (Model A).
This approach is adequate for planning isolated and well-defined water systems. With the introduction of the concept of
sustainability, the water systems interact with societal processes in the urban environment. We are then not any more dealing with
an isolated water system but with a complex adaptive system. For such systems the traditional planning models are not good enough.
A more integrated planning approach is needed (Model B). An important characteristic of this new approach is that the complexity of
the planning process is not combated but made manageable. As a result, during the process different space scales are handled
parallel, time plays a more important role and more actors are involved. It is an open process. Also more values of water are taken
into account. Different techniques for sustainable stormwater drainage are described. Based on experiences in the city of Malmö in
Sweden a practical approach for integrated planning of these types of drainage systems has evolved (Model B). As a result multiple
use of stormwater facilities has today been general practice in Malmö. The outcome of some sustainable stormwater projects is
presented.
Interactive implementation. G. D. Geldof*+
In the last decades it has become clear that improving the quality of the urban environment asks for an integrated approach and
stormwater source control. However, practice shows stubborn behaviour. Water managers did start to produce integrated water
plans, but only a few measures in these plans are really implemented. This paper uses complexity science building bricks to handle
above mentioned problem. Instead of the traditional serial approach a parallel approach is introduced. This is called Interactive
Implementation. Interactive Implementation shows the characteristics of a learning process, where people act parallel and learn
from each other’s mistakes. Practice and science are interwoven. Parts of the vision are constructed, even when the financing of the
whole vision is not fully organised. Most of the public and political support reveals itself as an emergent property. Spatial integration
takes place on a large scale (the vision) and integration of water, traffic, recreation, education and culture takes place in smallscale practical projects. In new urban areas to be developed, the traditional serial approach most of the time suffices. However, in
existing urban areas the process of Interactive Implementation has to be applied. The paper illustrates how Interactive
Implementation can be put into practice.
Development of filters for secondary treatment of stormwater. H. Genç-Fuhrman*+; P. S. Mikkelsen; A. Ledin
Presented by Hülya Genç-Fuhrman, Technical University of Denmark, Denmark
This study combines a literature survey and laboratory experiments, with a long-term goal of developing an effective technology for
the secondary treatment of stormwater. In the review part, several sorbents which will act as filtration materials in the secondary
treatment step are investigated to help in the decision of which to test experimentally. The laboratory part of the study included
batch tests using several sorbents for simultaneous removal of heavy metals (As, Cd, Cr, Cu, Ni and Zn) at the initial pH of 6.5. The
results presented here are restricted to Zn, and indicate that Zn removal efficiency varies with the initial heavy metal
concentrations. The affinity of the sorbents towards Zn is: fly ash (FA) = bauxsol coated sand (BCS) > alumina > spinel (MgAl2O4) >
granulated activated carbon (GAC) > activated bauxsol coated sand (ABCS) > bark = natural zeolite (NZ) > iron oxide coated sand
(IOCS) > sand. Of these, Danish discharge value of 110 µg/L can be met for the initial Zn concentrations as high as 13.5 mg/L by using
alumina, FA or BCS. It is suggested that high surface area and porosity of alumina and negatively charged surfaces of FA and BCS may
have favored the removal. Sand and IOCS have the least Zn removal efficiencies, and although the results were somewhat expected
for sand, the relatively low performance of IOCS was not expected; and it is postulated that this may be due to the experimental
conditions (i.e. the near neutral pH, relatively low sorbent dosage and the presence of competing cations).
Integrated stormwater strategies to reduce impact on receiving waters. J. German*+; M. Vikström; G. Svensson; L.-G. Gustafsson
Presented by Jonas German, CIT Urban Water, Sweden
The aim of this study was to evaluate the influence of the city of Örebro, where it is no com-bined sewers, on pollution load to the
receiving water the river Svartån. GIS and hydrologic modelling was used to achieve this. The subcatchments in the city that
accounted for the highest discharges of pollutants was identified and measures to reduce the load from these subcatchments was
proposed. It was shown that stormwater was the most important source of heavy metals to Svartån, but the influence of stormwater
on the nutrient load was negligible. Further, one stormwater discharge was identified that accounted for about 1/4 of total pollution load from storm-water on Svartån. Even if this subcatchment yielded the highest amount of pollutants, the highest
concentrations was found from small homogeneous catch-ments. It was concluded that studies like this could be a valuable tool in
the stormwater management.
Phenomenological modeling of wastewater treatment plant influent disturbance scenarios. K. V. Gernaey*+; C. Rosen; L.
Benedetti; U. Jeppsson
Presented by Krist V. Gernaey, Lund University, Sweden
Deterministic wastewater treatment plant (WWTP) models are useful for simulation-based evaluation of design, upgrade and control
alternatives on WWTP performance. However, due to high requirements of measurement campaigns in terms of time and economic
resources, many simulation studies suffer from the limited availability of long influent flow rate and concentration time series
representing realistic influent disturbance scenarios. In this paper, a phenomenological modeling approach for generation of WWTP
influent disturbance scenarios is proposed, with focus on the generation of dynamic WWTP influent flow rate scenarios. Model block
principles are presented, and are illustrated with simulation results and full-scale plant data. The comparison with real data shows
satisfactory agreement with model results.
Sediment characteristics and its impacts to water column in Han-river, Seoul, Korea. K.-I. Gil; J. Kang; J. Yoon; G. Cho; L.-H.
Kim*+
Presented by Lee-Hyung Kim, Kongju National University, Korea, Republic of
Various pollutants may be adsorbed to the sediments accumulated on the bottom of rivers or lakes. These sediments may accumulate
over long periods and can act as new pollutant sources to the overlying water many years after the water quality has improved. It is
the reason that these sediments are classified as one of nonpoint source pollution. Nonpoint source pollution remains a major cause
of water degradation in Han-river, Seoul, Korea. Recently, the ministry of Environment, Korea, developed the program of total
maximum daily load for Han-river to protect the water bodies from possible pollutants. The Han-river, the largest river in Korea, is
the primary drinking water source for the 20 million people that live in Seoul metropolitan areas. The sediments in the river are
highly polluted due to inputs from upstream tributaries as well as partially treated municipal wastewaters. To characterize
concentrations of the sediments, the disturbed and undisturbed sediment samples were periodically collected at 8 points during 8
months. It was analyzed for pH, water content, total solids, ignition loss, TKN, TP and TCOD. This paper will summarize the
characteristics of sediments with time and locations, and the effects of dredging on concentration changes in sediment.
Stakeholder involvement in wastewater treatment design. D.J. Gilmour*+; D.J. Blackwood; K. Picken
Presented by Daniel Gilmour, University of Abertay Dundee, United Kingdom (Great Britain)
The design option appraisal stage of new water industry capital investment projects involve greater levels of complexity than those
generally encountered in other stages of the design process. It is at this stage that the issues related to sustainable development will
be introduced, as decisions are multi-stakeholder and therefore decision criteria that reflect the views of a wide range of
stakeholders with a range of different viewpoints need to be incorporated. This paper describes a case study which maps information
25
flows, identifies decision criteria and evaluates the extent of stakeholder involvement in the design stage of a major UK wastewater
system project. A mapping technique was developed to document and represent the flow of information during the decision making
process. An in-depth study of the information flows enabled the researchers to establish the extent to which sustainability criteria
were actually used. This was compared with recognised sustainability criteria identified in previous research involving the authors to
allow an assessment of the effectiveness of stakeholder representation. Recommendations are given regarding ways of improving
stakeholder involvement in water industry asset investment decisions.
Quality of stormwater runoff from paved surfaces of two production sites. I. Gnecco*+; C. Berretta; L.G. Lanza; P. La Barbera
Presented by Ilaria Gnecco, University of Genova, Italy
In order to investigate stormwater pollutant loads associated with different anthropic activities and the related pollutant build-up
and wash-off processes, two pilot sites have been equipped in the Liguria Region (Italy) for monitoring first flush water quality in a
gas station and an auto dismantler facility. TSS, COD, HCtot and heavy metals in dissolved form (Zn, Pb, Cu, Ni, Cd, Cr) have been
analyzed during the monitoring campaign (started in February 2004). Stormwater flow and quality data collected in both production
sites confirm that EMC values are significantly higher than those observed in urban site. In the auto dismantler site, the EMC values
for TSS, COD and HC largely exceed the standard values (EC 91/271). Contrary to urban surface runoff, scarce correlation between
TSS and COD concentrations is observed in runoff from both production sites. The occurrence and nature of the pollutant load
connected to first flush flows is discussed by inspection of the M(V)-curves that are provided for all monitored water quality
parameters. Significant first flush phenomenon is evidenced for TSS and HC, while such a clear behavior doesn’t emerge for heavy
metals. Hydrologic and climatic characteristics (ADWP, rainfall intensity/depth) appear to scarcely affect the build-up and wash-off
processes.
An operational modelling tool for sewer networks management. F. Gogien*+; G. Manic; M. Zug
Presented by Frederic Gogien, Veolia environnement, France
Managing sewerage systems is a highly complex task due to the dynamic nature of the facilities. Their performance strongly depends
on the know-how applied by the operators. In order to define optimal operational settings, a decision support tools based on
mathematical models have been developed. Moreover, an easy-to-use interface has been created as well, aiding operators who
presumably don’t have the necessary skills to use modelling software. The site where the tool have been developed and set up is the
city of Saint-Malo (Brittany, France). The "classical" modelling study has provided a full validated model for hydraulic and pollutant
transfers that can be ran for long term simulations. The operational tool contains a data treatment module to format the input of
the model, a simulation launcher that communicates with the "commercial" software using the Application Programming Interface
and a results analyser to provide directly the needed results. Two applied examples are detailed in the paper, the first one dealing
with self-monitoring balance sheets generation, and the second one showing a way to compare the efficiency of different managing
rules for real time control. The final aim for using this type of tool is to preserve the quality of receiving waters.
The CSO problem in the Besos Basin. A general approach for a mediterranean basin. M. Gomez*+; J. Navarro; P. Serra; F. Castillo;
S. Menéndez
Presented by Manuel Gomez, UPC - ETS ING. CAMINOS, Spain
In this paper, the process developed in the Besos River basin to reduce the CSO problems is presented. Although these problems are
well known and have been addressed in many countries, in Spain a few projects about this topic have been developed. The problem
of CSO is more acute in basins with rivers showing low discharges, and crossing urban areas that decide to restore the fluvial system
close to the city. The selected basin has 84 outlets with 40 of them showing overflows in case of light rainfalls, throwing pollution
and debris into the river bed. The municipalities created a local authority, the Consorci per a la Defensa de la Conca del Besós, with
the purpose to improve the water quality in the river basin. The CSO volumes and the annual frequency was proposed to be reduced
to one half and one third, respectively. This was decided as a consequence of an economical analysis made for this project. Seven
detention basins were proposed and the methodology is going to be extended to the next tributaries.
Characterization heavy metal sources in a combined sewer system. C. Gounou; G. Varrault*+; J. Gasperi; S. Azimi; R. Moilleron; S.
Garnaud; V. Rocher; G. Chebbo
Presented by Gilles Varrault, University Paris 12, France
The aim of this work was to assess the contribution of main urban heavy metal sources to heavy metal loads in combined sewer
overflows (CSO). Use of source markers was a good way to achieve this objective. In order to facilitate this work, a two step method
was used. The first step discriminated the different pollutant entry pathways into the combined sewer (EPCS) in order to assess their
own contribution to CSO. In perspective, the second step shall consist of the determination of the main heavy metal sources for each
EPCS. Sampling of the different EPCS has been carried out and 23 metallic elements were determined by ICP-OES. Principal
component analysis (PCA) was applied to the experimental data and enabled us to select four elements as source markers. It
appeared that Pb and Fe are markers of roof runoff and to a lesser extent of street washing water. On the contrary, Na is a dry
weather flow marker. Use of these markers in the form of ratios like Na/Pb permits a very good discrimination of the three EPCS
studied.
Stormwater treatment trains in subtropical Australia - wetland and pond systems: How effective are they in improving water
quality and enhancing ecosystem biodiversity?. M. Greenway*+
Presented by Margaret Greenway, Griffith University, Australia
Sediment basins, wetlands and ponds are commonly used in subtropical Australia for stormwater storage and water-quality
improvement. A crucial question is: “How effective are these stormwater treatment devices?”. Wetlands and ponds, being “natural
systems”, also have the potential to enhance aquatic biodiversity. Our research efforts have focussed on monitoring water quality
and macroinvertebrates in a wetland system consisting of a sediment basin and two wetlands, and a pond system consisting of a
sediment basin (Pond 1) and five ponds. Reductions in TSS occurred in the wetland system during short, intense events but increased
in longer, more intense events due to resuspension. Reductions in TSS in the pond system largely occurred in Pond 1. TSS increased
in both systems in dry weather due to resuspension by ducks. NO3 decreased in both systems in wet and dry weather. NH4 increased,
probably due to ammonification of organic matter. PO4 decreased in both systems, but removal was highest in the pond system.
Neither system achieved TN and TP Water Quality Objectives on a regular basis, due to NH4, organic N and P. Macroinvertebrate
species richness increased in both systems.
The integration of urban drainage in the interdisciplinary SDSS for planning and controlling in river management – FLUMAGIS. O.
Gretzschel*; J. Möltgen; M. Uhl+
Presented by Mathias Uhl, University of applied Sciences Muenster, Germany
Spatial and planning support for the implementation of the European Water Framework Directive (WFD) requires interdisciplinary
approaches for assessment, deficit analysis and co-operative scenario investigation. The paper presents a part of the SDSS approach
from the FLUMAGIS-project. In the prototype several case-studies are developed to test the planning and assessment tools. This
comprises the representation of flowing waters and landscape ecological aspects as well as aspects of water and emission balances in
the study area of the upper Ems catchment (3740 km²) in the northwest of Germany. One focus of the project was the role of urban
areas affecting the river system in different ways, e.g. as priority pollutants from urban areas and hydrological stress caused by
storm water discharge. An overview of the applied and developed methods and functionalities in FLUMAGIS is given. Further more an
extract of the urban relevant case studies is offered. This comprises an integrated evaluation of river sections, considering
hydrological aspects as well as an emission balance of rainwater discharge. However, due to the high interdisciplinary approaches
only a few aspects can be described within this paper.
Practical aspects, experiences and strategies by using UV/VIS sensors for long-term sewer monitoring. G. Gruber*+; J. BertrandKrajewski; J. De Beneditis; M. Hochedlinger; W. Lett
Presented by Guenter Gruber, Graz University of Technology, Austria
An explosion-proof UV/VIS sensor has been available even in sewer systems for some years for simultaneous measurement of CODeq,
filtered CODeq, TSSeq and nitrateeq. This sensor allows in-situ real-time measurements with no sampling, no sample preparation and
no reagents. Three case studies are presented in this paper using this UV/VIS sensor for long-term sewer monitoring issues whereby
two different installation strategies are applied. The pros and cons of both different installation solutions are compared and
different calibration results during dry and wet weather conditions and long-term operational sewer monitoring experiences are
given in this paper.
The effect of climate change on urban drainage: An evaluation based on regional climate model simulations. M. Grum*+; A. T.
Jørgensen; R. M. Johansen; J. J. Linde
Presented by Morten Grum, PH-Consult, Denmark
That we are in a period of extraordinary rates of climate change is today evident. These climate changes are likely to impact local
weather conditions with direct impacts on precipitation patterns and urban drainage. In resent years several studies have focused on
revealing the nature, extent and consequences of climate change on urban drainage and urban runoff pollution issues. This study
uses predictions from a regional climate model to look at the effects of climate change on extreme precipitation events. Results are
presented in terms of point rainfall extremes. The analysis involves three steps: Firstly, hourly rainfall intensities from 16 point rain
gauges are averaged to create a rain gauge equivalent intensity for a 25 x 25 km square corresponding to one grid cell in the climate
model. Secondly, the differences between present and future in the climate model is used to project the hourly extreme statistics of
the rain gauge surface into the future. Thirdly, the future extremes of the square surface area are downscaled to give point rainfall
extremes of the future. The results and conclusions rely heavily on the regional models suitability in describing extremes at timescales relevant to urban drainage. However, in spite of these uncertainties, and others raised in the discussion, the tendency is
clear: extreme precipitation events effecting urban drainage and causing flooding will become more frequent as a result of climate
change.
Accumulation-washout description in modelling event mean concentrations of COD in combined sewer overflow. M. Grum*+; P.
Hallager; B.L. Jensen; K. Kærgaard; J. J. Linde
During heavy rainfall combined sewer systems discharge nutrients, organic matter and other pollutants into the surrounding surface
waters. Over the past 25 years efforts have been made to quantify pollutant loads discharged through combined sewer overflows
based on various modelling approaches. Models assuming discharge loads to be the result of the mixing of surface runoff and the dry
weather waste water flow miss some phenomena such as accumulation and subsequent washout. Other efforts incorporating a vast
amount of sedimentation, resuspension and biological processes have often lead to a large number of model parameters whose
values are practically impossible to determine. The study presented in this paper distinguishes itself from earlier works on two
accounts. Firstly, a parsimonious model for pollutant accumulation-washout has been identified based on measurements of CSO
event mean concentration (EMC) of chemical oxygen demand (COD) over a period of more than four years. Secondly, and perhaps
most interestingly, the same parameter set was found to be valid for the two CSOs studied. The data originate from two fairly
different CSO structures in the city of Odense, Denmark. The only CSO specific parameter required is the dry weather COD
concentration at the specific overflow structure. A term has also been introduced to account for the effect of extremely intense
rainfall events on the CSO EMC. Discussion is focused on generalisation.
Hydrological modelling in identifying the unintended rainfall-runoff contributions. M. Grum*+; B. N. Jacobsen; J. Nørremark; J. B.
Thyme
Continuous monitoring of performance is playing an increasingly significant role in both real time operation and in long term
management of urban drainage systems. This is combined with an increased realisation of the information that potentially can be
extracted from measured series of flow, water levels, substance concentrations, temperature, pump operation and others. Whilst on
the one hand leading to vast amounts of information heavy data, this development raises a number of non-trivial questions
concerning the analysis and interpretation measurement data. This paper presents a study in which hydrological modelling has been
used to identify unintended rainfall-runoff contributions to the sewer part of a separate sewer system. The modelling and
optimisation was done using the open source WaterAspectsTM modelling framework. An automated optimisation routine is used to
estimate model parameters. Input data to the model included rainfall measurements from a point rain gauge and monthly average
potential evaporation. This study also gives an initial insight into some of the advantages of case specific modelling approach. In the
discussion the authors looks at how the methodology can be used to evaluate the effects of investments made whilst also pointing to
some potential pitfalls of the approach.
The role of in-situ unit operation/process infiltration treatment on partitioning and speciation of rainfall-runoff. T. Guo; J.
Sansalone*+; P. Piro
Presented by John Sansalone, University of Florida, United States of America
Management decisions regarding the potential fate and toxicity of anthropogenic metal elements requires knowledge of metal
partitioning and speciation as mediated by in-situ control systems (ICS). This study focused on Cd, Zn, Cu and Pb, common
anthropogenic metal elements generated in the built environment and examined the influence of variable event-based hydrology and
passive ICS by an engineered partial exfiltration reactor (PER) system on partitioning and speciation. The feasibility and efficiency of
the PER as an in-situ stormwater runoff control strategy to attenuate levels of metal elements was evaluated. Results indicate that
higher rainfall intensity resulted in higher dissolved fraction (fd) values for influent Zn, Cu and Cd, but did not have a significant
influence on partitioning of Pb. Speciation indicated that divalent fractions of Cd, Zn, Cu and Pb were changed marginally by the
PER. Cu and Pb mainly complexed with organic matter in the influent, while carbonate complexes of these metals in the effluent
significantly increased. The PER consistently and statistically reduced all loadings of Cd, Cu, Pb and Zn for all examined events,
whether on a mass or concentration basis. As an unsaturated flow unit operation/process the PER can efficiently remove ionic or
complexed forms of metal elements. Such UOPs are a potential quality and quantity ICS strategy for rainfall-runoff.
Introducing APSWM - The Analytical Probabilistic Stormwater Model. Y. Guo*+
Presented by Yiping Guo, McMaster University, Canada
27
The analytical expressions forming the basis of the analytical probabilistic stormwater model (APSWM) were derived and verified in a
series of previous papers. Probabilistic description and representation of input storm events are the major difference between
APSWM and conventional stormwater models that use design storms to represent local rainfall conditions. In this paper, the
fundamentals of APSWM are summarized with an emphasis on comparing it with conventional stormwater models. This comparison
reveals the many advantages of APSWM and delineates better the applicability of APSWM for the planning and design of stormwater
management facilities. This comparison also identifies the limitations of both APSWM and the conventional design storm approach. A
wider and proper application of APSWM in engineering practice is what motivated this summarizing and comparison study.
Optimization of sediment trap configuration using CFD modelling for Indian drainage systems. K. Gupta*+; P. Mehta; T. Thinglas;
S.J. Tait; V. Stovin
Presented by Kapil Gupta, Indian Institute of Technology Bombay, India
The flow capacity of urban stormwater drainage channels in major cities of India are gradually being reduced due to increased
quantities of solid waste being introduced into these systems. During low flows, the solid waste forms deposits within these open
drainage channels. These must be regularly cleaned to ensure that the drains function at an optimal hydraulic capacity in order to
limit overflows. This places a significant burden on the operators of these systems. The erosion of deposits during high intensity
rainfall, combined with flooding can release significant amounts of pollutants into areas adjacent to these channels. This can have a
high economic and social impact as these areas have experienced a high level of development in recent years. One of the ways to
minimize deposits, and reduce the management burden, is to provide invert traps in the drainage system at pre-determined locations
to reduce the deposits and concentrate the solid waste at a smaller number of known locations . Once full, these can then be
emptied within a planned programme of work. This paper describes the initial sediment retention studies of various configurations of
invert trap using Computation Fluid Dynamics (CFD) modeling. A 2-D CFD model, using the FLUENT software, was implemented to
solve the continuous flow phase and to estimate the flow patterns. This study has examined three different trap configurations with
different types of particle type over a range of six discharges (low, medium and high). Early results indicate that the trap
performance is sensitive to the discharge and the trap configuration. Further work is in progress to determine the optimal shape for
trapping efficiency of solids under Indian conditions.
Fault diagnosis for validation of hydrometric data collected from sewer networks. F. Hamioud*+; C. Joannis; J. Ragot
Presented by Farida Hamioud, Laboratoire Central des Ponts et Chaussées, France
The measured values provided by sewerage monitoring systems require a processing for their validation. This paper applies a method
of diagnosis on a set of measurements collected from the sewer network of Nantes (France), This method relies on the overall
information redundancy, which is captured in a set of linear models. These models generate residuals, which are tested for the
detection and localisation of potential faulty sensors. The diagnosis uses the theoretical signature matrix, which is derived from the
structure of the models, and qualitatively describes the effect of a faulty measured variable on the residual of each model. Then,
fuzzy logic is used to compare the theoretical signature matrix and the actual values of observed residuals, thus enabling the
identification of faulty sensors. An example is provided to illustrate this method.
Accounting for uncertainty in urban drainage system performance assessment using safety factors applied to runoff. A. C.
Hansen*+; L. Liu; J. J. Linde; O. Mark; P. S. Mikkelsen
Presented by Anca Cecilia Hansen, NIRAS, Denmark
A crucial step in looking for causes of flooding is a thorough understanding of the uncertainty related to model-based performance
assessment of urban drainage systems. This study introduces a methodology for design and analysis of urban drainage systems that
takes into account the uncertainties related to the model inputs and parameters. The methodology has the advantage that it can be
applied in different stages of the design process irrespective of the complexity of the calculations. For less complex situations the
first order analysis of uncertainty is used, while the Monte Carlo method is used for more complex situations. In both cases the
uncertainty analysis leads to a safety factor, which can be multiplied by the storm water runoff as part of the design procedure. The
safety factor can be calculated for any desired confidence level. The method considers only statistical uncertainties and therefore
needs to be further developed.
On the selection of rainfall-runoff algorithm in Canada. D. Hansen*+; S. Ranade; C. R. Hansen
Presented by David Hansen, Dalhousie University, Canada
Choice of rainfall-runoff algorithm is obviously a central aspect of urban drainage design. Although it is known that the size and
imperviousness of the watershed have a bearing on the choice of algorithm, there is in Canada little evidence that any one algorithm
is strongly preferred by most practitioners for application to a given design setting, and less evidence of any one algorithm being
broadly specified in Canadian municipal regulations. If a given algorithm is chosen or specified, the reason for the choice is often
unclear. The fact that the watershed in question does not yet exist (as an urbanised watershed) and that flow over impermeable
surfaces and through sewers is more a question of hydraulics than of hydrology indicate that greater consistency in engineering
practice should exist. No single commercial software package can execute all known algorithms. An overview of Canadian practice is
presented, with reference to drainage design guidelines published by major municipalities in representative regions of the country.
The main rainfall-runoff algorithms in use are listed, with brief comments on their respective hydrologic advantages and
disadvantages. A ‘best-practice’ ranking of these algorithms is suggested, with qualifications. It is shown that there is little
correspondence between the obvious advantages of some of the algorithms as compared to their prevalence of recommended use.
Recommendations are made pertaining to standardization of procedures.
Filter media for stormwater treatment and recycling: the influence of hydraulic properties of flow on pollutant removal. B. E.
Hatt*+; N. Siriwardene; A. Deletic; T. D. Fletcher
Presented by Belinda Hatt, Institute for Sustainable Water Resources, Australia
Improved urban water management in Australia is of national importance. Water resources are stretched and urban runoff is a
recognized leading cause of degradation of urban waterways. Stormwater recycling is an option that can contribute to easing these
problems. Biofilters are effective structural stormwater pollution control measures with the potential for integration into stormwater
treatment and recycling systems. However, premature clogging of biofilters is a major problem, with resulting decreased infiltration
capacity (and hence the volume of stormwater the system can detain) and increased detention time. This paper presents preliminary
findings with respect to the effect of clogging on pollutant removal efficiency in conventional stormwater filter media. A onedimensional laboratory rig was used to investigate the impact of clogging on pollutant removal efficiency in a conventional
biofiltration filter media (gravel over sand). Both the individual gravel layer and the overall multi-filter were highly efficient at
removing suspended solids and particulate-associated pollutants. This removal efficiency was consistent, even as the filters became
clogged. Removal of dissolved nutrients was more variable, with little reduction in concentrations overall. Although preliminary,
these results challenge the concept that increased detention time improves the treatment performance of stormwater filtration
systems.
Risks and problems in urban stormwater management from a Pan European end user perspective. M. B. Hauger*+; A. Ledin; P. S.
Mikkelsen
Presented by Mikkel Boye Hauger, Environment and Resources DTU, Denmark
Three sources of information is collected with the purpose of getting an first impression of what risk and problems in the urban
stormwater system is perceived as the most significant. The information was collected from European end users, European
researchers and Danish water professionals, Data was organised in a matrix based on identification of objects and types of risk for all
mentioned risks and barriers. The data was organized in 7 different objects and 7 different types of risk. Results show that there is
good agreement between the different groups’ perception of risk and problems although there also are some disagreements. All
groups had great concerns for risks related to BMP’s and new technologies and risks related to the environment. Risks related to
hydraulics and volumes were ranked as the most important type of risk by all three groups. Observed differences identified between
European and Danish end users illustrate that risks and problems are not perceived in a homogenous manner across Europe.
Indicators of hazard, vulnerability and risk in urban drainage. M. B. Hauger*+; J.-M. Mouchel; P.S. Mikkelsen
Presented by Mikkel Boye Hauger, Environment and Resources DTU, Denmark
An alternative definition of risk is proposed as risk being a function of the hazard, which is related to the risk source and the
vulnerability, which is related to the risk object. The same hazard will not cause the same effect on all risk objects. Therefore
vulnerability is introduced as a system dependant property to be the link between the hazard and the effect so that the combination
of the occurrence of a hazard and the vulnerability of an object results in the effect. In risk communication indicators are helpful
since they help to simplify the message that has to be communicated. Three examples (pluvial flooding of sewers, dissolved oxygen
depletion in streams and discharge of chemicals to receiving waters) show that dependant on the risk problem possibilities for risk
reduction lies either at the risk source or at the risk object. Therefore it is important to have indicators that can be used when the
possibilities of risk reduction are analyzed.
Radical and gradual environmental innovations in urban water management - could they be friends?. D.L.T. Hegger*+; B.J.M. Van
Vliet; A.R. Mels
Presented by Dries Hegger, Wageningen University, Netherlands
This paper deals with the socio-cultural aspects of environmental innovations in urban water management, comparing two categories
of cases: disconnection of rainwater from the sewage system and Ecological Sanitation. The former is a gradual innovation that has
become official policy in The Netherlands. The latter is a radical innovation that has been implemented in several demonstration
projects in Western Europe. After studying the cases, it can be concluded that gradual innovations such as disconnection of rainwater
in the long run act as a stepping stone for radical innovations such as Ecological Sanitation, not only from a technical, but also from a
socio-cultural viewpoint. Traditionally, demonstration projects function as stepping stones for technological change. At least as
important as their technological features is the organisation of such projects. Furthermore, the role of the citizen-consumer in the
planning phase of projects and the actual use phase of new technologies is crucial. To build trust in technologies, it is required to
fine tune new technologies to the needs of citizen-consumers. For a successful use of stepping stones in technological development,
there should be deliberate experimentation, not only with different technological solutions, but also with different social
constellations.
Monitoring network design using multiple storm events. G. J .R. Henckens*+; R.P.S. Schilperoort, F.H.L.R. Clemens
Presented by Guy Henckens, Witteveen+Bos, Netherlands
This paper presents a complete description of an (improved) optimisation algorithm for monitoring networks, based on a genetic
algorithm. To extend the applicability of the original algorithm, multiple storm events are used in series to calculate the best
possible monitoring locations. Next to the mathematical background of the algorithm, possible optimisation choices are discussed
including required information overlap, the exclusion of certain manholes and the parameter set to be used. Based on practical
experience it can be concluded that the presented method can reduce monitoring costs and/or increase the reliability of the
network.
Modelling of a sewage network: Contribution to the management of pollution risks at the Haute-Sûre drinking water reservoir.
E. Henry*+; K. Klepiszewski; D. Fiorelli; A.-M. Solvi; A. Weidenhaupt
Presented by Emmanuel Henry, CRP Henri Tudor, Luxembourg
The presented project focuses on the generation of a model of a large rural combined sewer network. Objectives of the modelling
are the development of a management and control tool for the system manager and the validation and optimisation of the efficiency
of designed drainage facilities. Because of the catchment structure, the real time control component of the model has to consider
the effects of long residential times, especially in pressure pipes, and of spatially varying rainfalls. The project is of national concern
in Luxembourg because the “Haute-Sûre” storage lake, which is the main receiving water in the catchment under investigation, is a
drinking water reservoir serving 70% of the Luxembourg population. Therefore a wide combined sewer system with a central waste
water treatment plant downstream of the storage lake was favoured over several decentralised systems discharging into the lake. In
fact, the implementation of EU water directives requires a refurbishment of many drainage and waste water treatment systems in
Luxembourg. Since a lot of regions in Luxembourg have similar properties as the investigated system, some results of the project can
be exemplary for other catchments.
Urban drainage and the EU Water Framework Directive – A Swedish perspective. P. Hjorth*+
Presented by Peder Hjorth, Lund University, Sweden
Swedish urban water management has traditionally been a self-contained activity with limited objectives. Generally, it has been
controlled by standards (related to the conditions at the exit of the outlet pipe) that tend to be uniform all over Sweden. Following
the adoption of the EU Water Framework Directive (WFD), urban water management has to become more holistic and fully
integrated into drainage basin based water management. WFD introduces a two-pronged approach. It does define some standards for
point sources but, in addition, imposes requirements on water quality and ecological status of surface water, groundwater, and
coastal water areas. The latter requirements call for management of diffuse pollution, which means that we must have an integrated
land- and water planning. In addition, WFD insists on cost-efficient management, where benefits should exceed costs. Thus, these
requirements force water utility managers into unfamiliar territory. The paper provides a brief historical account of the emergence
of municipal water and sewerage utilities in Sweden and goes on to discuss what it takes to cope with the challenges that the WFD
imposes on the sector, with a special focus on urban drainage. Parallels are drawn to US experience after the enactment of the
Clean Water Act.
Assessment of CSO loads – based on UV/VIS spectroscopy by means of different regression methods. M. Hochedlinger*+; H. Kainz;
W. Rauch
Presented by Martin Hochedlinger, Graz University of Technology, Austria
The use of UV/VIS-spectroscopy for water quality measurements is based on the solution of the correlation between the surrogate
parameter absorbance and the resulting equivalence parameters. The coherence of absorbance and equivalence parameters
(CODtot, CODsol, TSS) will be solved in this paper with different regression methods. The correlation of absorbance and
29
concentrations are analysed based on linear regression methods, model tree regressions, multivariate regression methods and
support vector machines using sequential minimal optimisation algorithm. For this purpose the regression methods are calibrated on
three 24 hours measurement campaigns of a combined sewer measurement station situated in the combined sewer overflow chamber
in Graz (Austria). The online measurement station has been conveying data for more than 2½ years up to now. Finally, the load
calculation based on the different regression methods and its comparison demonstrate that an apparently complex model does not
inevitably lead to accurate concentration values due to possible model overfitting. Hence, the paper points out the possibilities and
the drawbacks of spectroscopy measuring in sewers and the arising concentration values.
Influence of urbanization on trends of annual, seasonal, and short duration rainfall amounts in Houston. P. Hooshialsadat; S. J.
Burian*+; J.M. Shepherd; F.G. Edwards
Presented by Steven Burian, University of Utah, United States of America
Past studies of precipitation in urban areas have suggested cities influence spatial and temporal rainfall patterns. However, in the
United States (U.S.), quantification and statistical verification of the modification of long-term trends of rainfall characteristics by
urbanization has been difficult because of sparse spatial coverage of rain gauges and insufficient record lengths. The data limitations
have been reduced during the second half of the twentieth century as numerous cities in the U.S. experienced rapid growth with
several having sufficient raingage coverage in the existing urbanized area, nearby urbanizing areas, and adjacent rural areas to
provide a framework to assess urban effects on long-term rainfall patterns. The longer records corresponding to periods before,
during and after rapid urbanization permit a more thorough analysis of trends and statistical verification of the effects of
urbanization on rainfall variability. The study presented herein involved the analysis of long-term trends of annual and warm season
rainfall amounts and the annual maxima of short duration (e.g., 24-hr, 12-hr, 6-hr, 1-hr) rainfall amounts recorded in the Houston
metropolitan area and climatological upwind and downwind regions. The observed trends were related to urbanization of Houston
during the second half of the twentieth century and the statistical significance was judged by linear regression analysis and
nonparametric statistical tests.
Research and evaluation of CSO treatment technologies "SPIRIT21". N. Horie*+; M. Kabata; H. Sano
Presented by Nobuyuki Horie, Japan Institute of Wastewater Engineer Technology, Japan
The early sewer systems were built in Japan as combined sewer system (CSS), which played an important role in urban development.
In recent years, pollution of receiving waters by combined sewer overflows (CSOs) conveying large oil balls was widely reported and
the Ministry of Land, Infrastructure and Transport (MLIT) addressed this issue by establishing “CSS Advisory Committee” with a
mandate to report on CSS improvement in Japan. This study was followed by publications of Guidelines of CSO control by the Japan
Sewage Works Association, and amendment of Enforcement Ordinance of Sewage Law including CSO control. To develop appropriate
technologies, MLIT initiated a project called “Sewage Project, Integrated and Revolutionary Technology for the 21st Century (SPIRIT
21)”. The project is operated under close cooperation among private sector, academic institutes and government. The project
conducts research in the following areas of CSO treatment and instrumentation: (a) debris removal (screening), (b) high rate
filtration, (c) coagulation and separation, and (d) disinfection, and (e) measurement and control instrumentation. 24 technologies
were proposed in all by the private industry and proceeded to evaluation by field test in 13 cities. All technologies were tested
successfully and are proposed for use in Japanese municipalities addressing CSO problems.
Sewer system protection against large scale floods – modelling, evaluation and design - Prague case study. D. Hrabák; S. Hanák;
K. Pryl*; P. Kuba; T. Metelka+
Presented by Tomas Metelka, DHI Hydroinform a.s., Czech Republic
In August 2002 the Czech Republic was hit by devastating floods, the biggest natural disaster in modern Czech history. In some areas
the floods - which affected over one third of the country - were the worst in the last 500 years. These floods were caused by large
rainfall events following immediately one after the other. The Prague sewerage network, as well as the central waste water
treatment plant (CWWTP), was also hit by the floods in August 2002. Rising water in the Vltava River flooded the CWWTP and
prevented the outflow of wastewater. Together with direct runoff caused by a local storm, the system was highly overloaded due to
the high water level in the river, closing flood defense caps and overflowing of outlets from the main sewers beneath the city.
Measures to remedy this disaster began immediately in autumn 2002. A great deal of attention was focused not only on protective
measures against floods caused by huge rainfalls which occurred in the upstream part of the Vltava river catchment area, but also on
measures to prevent a “self-flooding” of the city, caused by a combination of floods and urban waters transported through the
Prague sewer system. The project consists of the following phases - evaluation of the sewer system operation during the August 2002
floods in Prague, design of new flood protective structures, proposal for an operation scheme for different flood scenarios,
evaluation of designed structures and various scenarios using mathematical models.
Hydrologic regionalization impacts on wet-weather control selection. W. C. Huber*+; W. J. Wells
Presented by Wayne C. Huber, Oregon State University, United States of America
Continuous simulation is performed using the U.S. Environmental Protection Agency (USEPA) Storm Water Management Model (SWMM)
to evaluate regional differences around the United States in hydrologic and water quality performance of wet-weather controls.
Controls are characterized as being limited by peak inflow rate (i.e., any device with little or no storage, such as screens, filters,
and some proprietary devices) or by storage capacity (e.g., ponds, tanks). For flow-limited devices, results are presented in the form
of percentage of annual runoff volume captured (passing through the device) for a given inflow capacity. For storage-limited devices,
results are presented in two forms: percentage of annual runoff volume captured as a function of unit basin size and drawdown
(drain) time, and as percentage of total suspended solids captured, for the same two variables. Regional differences are apparent,
driven mainly by variations in rainfall patterns around the country.
Hydrologic and water quality performance of four bioretention cells in Central North Carolina, USA. W. F. Hunt III*+; L. J.
Sharkey; J.T. Smith; W.G. Lord; A.R. Jarrett
Two paired, field-scale bioretention studies (in Greensboro and Louisburg, NC, USA) have been conducted to study (1) hydrologic
performance and (2) nutrient removal of phosphorus and nitrogen. In Greensboro, one cell was conventionally drained; the other
contains a zone of internal water saturation (IWS) of 0.45m. They were continuously monitored from June, 2002, to December, 2004.
During outflow events, TP concentrations were significantly lower (P<0.01) in the cell with an IWS zone, but these results were
confounded by different phosphorus levels in each cell’s fill soil. No significant difference existed among nitrogen removal. In
Louisburg, both cells were conventionally drained and were comprised of low phosphorus fill soil. The bottom of one cell was lined
with 20 mil plastic; the other was unlined. Estimates for exfiltration, outflow, and evapotranspiration were made by comparing
each’s cell’s outflow and inflow. During the summer of 2004, approximately 25% of inflow exfiltrated the cell, another 25% left via
the cell’s underdrains and 50% of the inflow was released as ET. The importance of using low P-Index soil media for bioretention was
reconfirmed, as average outflow concentration were 40-53% lower for TP and 25-60% lower for TN when compared to inflow
concentrations for 9 storms.
Sustainable urban drainage and public participation in Albertslund, Denmark. H. Høg; S. Gabriel*+; A. Henze; M. Krayer von
Krauss
Presented by Søren Gabriel, HME a/s, Denmark
In the city of Albertslund, Denmark, the rainwater collection system has been designed with two goals in mind: i) evacuating and
filtering runoff rainwater, and ii) developing rainwater detention ponds of a high aesthetic and recreational quality. The ponds have
been the focus of much public attention, and there is little tolerance for pollution of the ponds by metals and oils. Thus,
management of the ponds has been a high priority issue for the municipality of Albertslund. Partially due to the interest the citizens
of Albertslund have taken in the ponds, the city is today a leading example of public participation in Denmark. Representatives from
the residential areas of the city are part of a “Council of Citizens” that deals with topics such as waste, district heating and matters
concerning surface water quality and sewer systems. Since its inception in 1921, the Council has been very active in producing a
number of action plans, including an action plan for rain and wastewater management, an action plan for the wetlands within the
rainwater collection system, and a municipal Nature Plan. Throughout the years, Albertslund has tested a number of measures aimed
at improving the quality and function of the urban drainage system and the rainwater collection ponds, while at the same time
reducing the emission of pollutants to natural recipients. These measures include source control, sewer inspection and renovation,
the installation of oil separators, and the construction of special ponds designed for cleaning purposes.
Empirical analysis of sprinkling of recycled wastewater. Y. Ishikawa*+; M. Iida; K. Yoshida
Presented by Yoshihiro Ishikawa, CTI Engineering Co.,Ltd, Japan
Treated wastewater is used as a valuable urban water resource. It is used mostly as non-potable water for such purposes as toilet
flushing and clear streamflow restoration. Only less than one percent of recycled water is used in Japan. Against such a background,
sprinkling advanced treated wastewater (recycled wastewater) over water-retaining pavement in the hope of helping clean the road
surface(cso) and alleviate urban heat island phenomena has been gaining greater attention as a new application of recycled water. In
this study, the expected effects of recycled wastewater sprinkling and the problems involved in sprinkling such as odors were
verified by conducting field tests, and the feasibility of sprinkling recycled wastewater was examined.
Co-operation of inhabitants and public authorities. E. Jacobs*+
Presented by Eilard Jacobs, Sewerage and Watermanagement Service, Netherlands
In the Netherlands as a low-lying country, high groundwater tables cause problems in some houses. The actual cause of these
problems is different in different cases, but a problem is always that the responsibilities are complex. The official policy is that not
only there is a responsibility for the public bodies; also the owners of the houses themselves have a responsibility. From the point of
view of the inhabitants however, high groundwater tables are something they cannot influence themselves so it is a public
responsibility. The process of co-operation between the municipality of Amsterdam and a group of inhabitants shows the
development in a specific case. By informing each other and practical co-operation an atmosphere of mutual trust is growing. But
the proof of the pudding will be when real measures have to be taken and both the municipality and the owners have to invest.
Evaluating hydrodynamic behaviour and pollutant removal in various stormwater treatment pond configurations. K. Jansons*+;
J. German, T. Howes
Presented by Ketah Jansons, University of Queensland, Australia
This research aims to establish a relationship between pond geometry and hydrodynamic behaviour. In this paper the mixing quality
and pollutant removal efficiency of seven stormwater pond configurations are evaluated. Both two-dimensional depth averaged flow
simulations (Mike 21) and a compartmental modelling approach are employed in this process. Outcomes of this study reveal the
common design assumption that all stormwater treatment ponds are either plug flow or well mixed is flawed. Results also indicate
that square configurations are more susceptible to the formation of mixing imperfections including stagnation, recirculation and
short-circuiting than long narrow configurations. The presence of mixing imperfections were also found to adversely impact pond
pollutant removal capacity.
Use of geographic information systems for estimation of urban stormwater runoff - A case study. K. V. Jayakumar*+; E. Venkata
Rathnam
Presented by Jayakumar Kandathil Valappil, National Institute of Technology Warangal, India, India
Stormwater runoff volumes in urban areas are considerably higher than runoff volumes in non-urban areas because impervious
surfaces such as paved roads, parking areas and roofs prevent rainfall from infiltrating into ground. For planning stormwater
management systems in urban areas, knowledge of stormwater runoff volume and peak flow rate due to rainfall is essential. In most
cases, it is not always possible to measure direct runoff at desired time and location. Remote sensing technology combined with
geographic information system (GIS) can augment the conventional methods to a great extent in rainfall-runoff studies. The purpose
of the present paper is to illustrate how GIS can be used to estimate the urban runoff/ stormwater at Musa river watershed, an
ungauged urban area in the city of Hyderabad, India. Natural Resources Conservation Service- Curve Number (NRCS-CN) method and
rational formula are used for estimation of stormwater generated from various rainfall events. A grid size of 10 m was adopted in the
study. CN values estimated using GIS approach are used to derive the runoff coefficient, C, which is used for the estimation of peak
discharge using rational formula. The rational method gives the peak flow rate while, the NRCS- CN method computes the runoff
from a given rainfall event. A synthetic unit hydrograph for the study area has also been derived using the method developed in
India.
Flood frequency estimation for an urban catchment using continuous simulation. G. A. Jenkins*+; D.B. Newton
Presented by Graham Jenkins, Griffith University, Australia
Urban development of rural areas generally has a significant impact upon the hydrologic and hydraulic regime of nearby creeks and
rivers. The removal of vegetation and replacement with buildings and paved surfaces also significantly affects the water quality and
morphological characteristics of the receiving waters. An understanding of the hydrologic impacts of urbanization is essential for the
assessment of the ecosystem health of urban waterways, as well as for the prediction of flooding. This paper describes UrbSim,
which is a continuous simulation model of the rainfall and runoff processes in urban catchments. A daily rainfall-runoff model is
combined with sub-daily disaggregation and runoff routing algorithms through the sub-catchments, which are defined by the
watershed boundaries within the catchment. The model has been applied to a sub-tropical urban catchment, and the calibrated
model is used to estimate the flood frequency characteristics of the catchment. The study results show that the continuous
simulation model can be successfully used to extend the flood frequency characteristics where suitable long-term rainfall records are
available. The use of the continuous simulation model to extend the flood frequency characteristics allows a better understanding of
the impacts of flooding and the long-term morphological characteristics within an urbanized catchment.
Sediment retention in rectangular storage tanks: Computations with a mass transport model and comparison with laboratory
experiments. M. Jensen*+
Presented by Mogens Jensen, Kruger AS, Veolia Water, Denmark
A linear convection-dispersion-deposition model, in 1 length dimension (CDD1), for a rectangular storage tank, is applied for
computing the variation, over distance and time, of the vertical mean concentration C of suspended sediment. It is assumed, that
31
the deposition rate to the bottom is proportional to C. The deposition velocity Vp, is the constant of proportionality. The model is
used, for steady tank flow velocity V, to calculate the mass distribution (suspended mass + bottom mass + overflow mass) as function
of time and tank length, for a continuous constant mass inlet. Focus is given to the retention efficiency defined as (suspended mass +
bottom mass)/(mass inlet). The model is also used for comparison with a large set of laboratory experiments from one reference.
The purpose of this comparison, is to study the variation of Vp with the sediment settling velocity Vs, and with flow parameters
(Froude number etc.). The comparison shows that Vp/V does depend solely of the relative deposition (bottom mass)/(bottom
mass+overflow mass), for which the reference presents an empirical formula with 3 hydraulic parameters namely: Tank Froude
number, densimetric sediment Froude number and relative settling velocity Vs/V.
Road runoff treatment with dual porosity filtration - 18 m3/h subsurface pilot construction in Ørestad, Copenhagen. M.B.
Jensen*+; L. Bisballe
Presented by Marina Bergen Jensen, KVL, Denmark
In Orestad, - a 310 hectares development area in Copenhagen, storm water runoff is discharged into open canals that serve
recreational purposes too. Runoff from trafficked surfaces (i.e. road runoff) has to be cleaned to obtain high quality canal water.
Consequently roof runoff, which is discharged directly to the canals, and road runoff are handled in individual sewer systems.
Available techniques for wastewater treatment do not fulfill the requirements in Orestad regarding effluent quality, treatment
mechanisms and/or land consumption. This paper describes the development and preliminary testing of a “green” concept for highlevel road runoff treatment in dense urban areas. The concept is based on the patent-applied technology Dual Porosity Filtration
(DPF), which mimics natural solute transport processes in fractured till. The treatment facility is built from rigid horizontal nylon
sheets - supporting flow, interlaid by layers of low porosity filtering materials - supporting contaminants retention. Gravity forces silt
and clay sized particles to deposit in low porosity layers, thus avoiding clogging of flow supporting layers. Dissolved contaminants are
adsorbed while passing surfaces of the filtering material. No chemicals are applied. Maintenance of the facility is limited, and its
lifetime is estimated to > 20 years. Green space consumption is minimized by placing the facility belowground.
Analysis of one year weather radar data for use in a rainfall runoff model. M. Jessen*+; T. Einfalt; C. Golz
Presented by Markus Jessen, einfalt&hydrotec GbR, Germany
One year of continuous rainfall measurements from weather radar and raingauges have been analysed and prepared for use in a
hydrological rainfall runoff model. A major effort of data quality control (quality check and data correction) was required to produce
reliable data. The employed corrections included data modifications because of the occurrence of ground clutter, beam blockage
and bright band. The corrected and adjusted data compared well on raingauge stations not used for the adjustment process.
Development of a GIS-based expert system for on-site stormwater management. Z. Jin*+; F. Sieker; S. Bannermann; H. Sieker
Presented by Zhengyue Jin, Universität Hannover, Germany
Urbanization is accelerating worldwide. One of the negative effects of urbanization is the overloading of the city sewer system. To
solve this problem, on-site storm water infiltration proves very promising due to its near natural characteristics and multiple effects
on the drainage of stormwater runoff in urban areas. However, the judgment of whether a local area is appropriate to be drained in
this way and which infiltration measures are optimal is rather complex and involves analysing a set of influential factors. This
judgment depends on not only relevant theoretical considerations, but also a large amount of practical experience and the
availability of relevant data, as well. Such a judgment is an unstructured problem and relates to changeable knowledge. To fulfill
this task, the so-called expert system, or knowledge-based system, is introduced. One of the advantages of an expert system is that
it provides automation of expert-level judgement. This is extremely helpful when an expert-level judgment is needed repeatedly for
a large amount of cases, like in the planning of on-site stormwater infiltration systems for an entire city catchment. This paper
describes a self-developed expert system tool for developing rule-based expert systems, as well as a case study: using an expert
system for the selection of on-site storm water infiltration measures for the city of Chemnitz, Germany.
Changes of stream ecology along the urbanization gradient. I. Kabelkova+; G. Stastna*; D. Stransky; L. Malec
Presented by Ivana Kabelkova - Jancarkova, Czech Technical University - Faculty of Civil Eng., Czech Republic
A study analyzing changes of the ecological status of a small stream (the Botic, Prague) along the urbanization gradient is carried out
in order to identify major deficits and their causes. Quantitative assessment of benthic invertebrate fauna, river ecomorphology and
water quality is being performed. Results show a serious ecological degradation of the whole Botic Stream (benthic index of biotic
integrity indicates a very poor, poor and only once fair status) due to the combined effects of poor water quality (class IV or V
according to the Czech standards), ecomorphological deficits including serious impacts of dams and reservoirs and increased
hydraulic stress from the urban drainage system. The Botic Stream has a certain rehabilitation potential in the upstream rural region
whereas measures in the highly urbanized downstream catchment would bring no improvement of the biological status at present.
Dynamics of the nitrogen transformation in a shallow stream and possible interventions. I. Kabelkova-Jancarkova*+
Presented by Ivana Kabelkova - Jancarkova, Czech Technical University - Faculty of Civil Eng., Czech Republic
This paper presents the assessment of the efficiency of the main biological nitrogen transformation processes in a shallow welloxygenated river and conditions under which they are active and stabilize. The process dynamics was studied with the help of
mathematical modelling of two years on-line data series measured in a reach of the Toess River, Switzerland. The algal nitrogen
uptake was very stable and unaffected by most but frequent flood events. Daylight photosynthetic nitrogen uptake stabilized at 6
mgN m-2streambed h-1 (15°C), dark uptake on storage products at rates of 0.5-2.5 mgN m-2streambed h-1. Nitrogen uptake by
heterotrophic bacteria in the hyporheic zone was relatively constant at a level of 1.5-3.5 mgN m-2streambed h-1. Streambed
nitrification could establish only during periods with averaged daily concentration of at least 0.3 gNH4-N m-3 in river water for
several weeks. The maximum nitrification rate was 35 mgN m-2streambed h-1 for 3 gNH4-N m-3. The effects of reduced nitrification
in the WWTP and of river banks shading on a sudden ammonium peak were simulated. A river reach endangered by ammonium spills
should be kept open to sun to favour ammonium uptake by algae. In-stream nitrification reduces ammonium peaks efficiently but
leads to toxic nitrite concentrations.
The present situation of the sewage plan working-out by the stormwater runoff simulation models. K. Kamata*+; R. Takahashi;
G. Tsuchiya
Presented by Kozo Kamata, Japan Institute of Wastewater Engineering Technolo, Japan
This paper explains the procedure to apply the stormwater runoff simulation model to inundation analysis, characteristics,
applicability and problems of the model to utilize for the inundation analysis, with doing quantitative evaluation process. This study
shows the possibility of practical use to the inundation analysis in the scheme of the sewage plan in the future.
Development of an object oriented programming model for water transfer in Tehran metropolitan area. M. Karamouz*+; A.
Moridi; S. Nazif
Presented by Mohammad Karamouz, Amir Kabir University, Islamic Republic of Iran
In this paper, a system approach to water transfer from south east to south west of Tehran is discussed. By construction of this
channel, up to 7 cubic meters per second of mostly urban drainage water can be transferred from east to west in the region to
overcome the negative impacts of water rise in the east and to utilize the urban water drainage in the cultivated lands and for other
municipal applications in the west. The channel intercepts several local rivers and drainage channels and could partially collect
water from these outlets. In order to simulate the state of the system under different water transfer scenarios and water allocation
schemes, an object oriented simulation model has been developed. Using different objects, the user can change the allocation
schemes for any give demand points. An economic model based on conflict resolution methods is developed for resource planning in
the study area. KEYWORDS Object Oriented, Water Transfer, Urban Drainage, Conflict Resolution, Resource Planning
Metal and Organic Content in Gully pot Mixture. K. Karlsson*+; M. Viklander
Presented by Kristin Karlsson, Luleå University of Technology, Sweden
During the cleaning of the gully pot, water has to be added to the gully pot to remove all the sediment. This mixture of gully pot
water and sediment, as well as the “wash-water,” has to be taken care of. This paper considers the quality of the water phase of
this mixture, due to a wide spectrum of metals and organic substances. Three sampling sites were selected according to type of area
and traffic intensity. The samples were analysed for suspended solids (SS), heavy metals, PAH, DEHP, and NPEO. The highest total
concentration of metals was found either in the housing area or in the city with high traffic, depending on the type of metal. The
highest concentration of PAH was found in the city with medium traffic. Most of the metals and PAH were attached to particles. Even
if the concentrations were higher in the housing area, one will get higher amounts of metals from the city during the same period of
time. The comparison between guidelines and the blend showed that the concentration in the blend exceeds the discharge criteria
for most of the substances.
Assessment of extraneous water inflow in separated sewer networks. C. Karpf*+; P. Krebs
Presented by Christian Karpf, Dresden University of Technology, Germany
Separate sewer systems provide due to the separate transport and treatment of waste water and rain water an efficient sewerage
technology. But the advantage compared to combined system technology gets lost if the input of extraneous water exceeds the
capacity of the system. Especially the input of rainwater into the waste water pipes depending on the drained area is responsible for
an overload of the sewer system and the wastewater treatment plant (WWTP). In the paper the input of extraneous water induced
by groundwater and rainwater in different rural catchments in the City of Dresden is assessed. On the base of a hydrodynamic
network model a case study is carried out for one of these catchments. The analysis of the current status of the studied area allows
the identification of rehabilitation activities and, furthermore, gives an indication on their extent and effects.
Determining the background concentration of contaminants in a stormwater wetland. T.M. Kasper+; G. A. Jenkins*
Presented by Thomas Kasper, PORR Umwelttechnik, Austria
Urban stormwater wetlands have been widely embraced by the community as a beneficial part of the stormwater infrastructure.
Although a reasonably large body of research has been undertaken into the treatment efficiency of wetlands during storm events,
relatively little is known about inter-event processes. Environmental effects such as wind direction and speed, wildlife and other
anthropogenic activities have a significant impact on these processes. The development of a suitable model of these processes is
limited by a lack of fundamental data on the movement of contaminants within a stormwater wetland during these inter-event
periods. This paper describes a study that has been undertaken to determine the background concentration of suspended solids and
nutrients in a constructed stormwater treatment wetland. The study has included an intensive monitoring program throughout a
recently constructed wetland in Brisbane. The study has identified that design issues such as the characteristics of the inlet structure
play a significant role in the resuspension and movement of suspended solids through the wetland system. Wildlife and anthropogenic
activities are also identified as playing an important role during inter-event periods. However, it is clear that the distribution and
density of vegetation influence the removal of suspended solids and nutrients within the system during these inter-event periods.
Stormwater inflow prediction using radar rainfall data compressed by principal component analysis. K. Katayama*+; K. Kimijima;
O. Yamanaka; A. Nagaiwa; Y. Ono
Presented by Kyosuke Katayama, Toshiba Corp., Japan
This paper proposes a method of stormwater inflow prediction using radar rainfall data as the input of the prediction model
constructed by system identification. The aim of the proposal is to construct a compact system by reducing the dimension of the
input data. In this paper, Principal Component Analysis (PCA), which is widely used as a statistical method for data analysis and
compression, is applied to preprocessing radar rainfall data. Then we evaluate the proposed method using the radar rainfall data and
the inflow data acquired in a certain combined sewer system. This study reveals that a few principal components of radar rainfall
data can be appropriate as the input variables to storm water inflow prediction model. Consequently, we have established a
procedure for the stormwater prediction method using a few principal components of radar rainfall data.
Modelling constructed wetlands for CSO treatment in long-term pollution load simulation. I. Kaufmann*+; T. G. Schmitt
Presented by Inka Kaufmann, University of Kaiserslautern, Germany
In combined sewer systems an enhanced treatment of combined sewer overflow (CSO) is required, when augmented water quality
requirements are demanded or conventional CSO treatment does not meet environmental quality standards. Constructed wetlands
(CWs) have become the most common method to provide enhanced treatment of CSO in Germany. As simulation models are an
important tool in planning urban drainage systems, enhanced treatment devices need to be implemented in the computing
procedures. A new module for balancing constructed wetlands in long-term pollution load simulations was implemented in the
simulation model KOSMO. The module potentiates both the investigation of annually emitted volumes and loads and the estimation
of operational reliability (loading situation, inundation and dry periods) of constructed wetlands. Removal processes within the filter
layer of constructed wetlands are described in a simplified way. The model was applied in a simulation study for a large catchment.
Long-term simulations show that the model produces solid and adequate results. The results indicate e.g. that the CWs are a very
effective measure to reduce emitted CSO loads and concentrations for the investigated catchment.
Advanced stormwater runoff characterization. M. Kayhanian*+
Presented by Masoud Kayhanian, University of California at Davis, United States of America
During the past seven years the California Department of Transportation has developed an extensive stormwater characterization
program to evaluate the physical, chemical and biological quality of the runoff from their representative facilities. Initially the
program has utilized many laboratories and environmental consultants who may not have necessarily used the same method of
sample collection, quality assurance and quality control, data reporting and data validation standards. Faced with this deficiency, a
set of standard protocols and several software tools were developed to improve the consistency among all characterization studies
and enhance the quality of water quality data. Software tools developed to deal with these problems include: 1) automated data
validation, 2) hydrologic utility, 3) rational database, and 4) data analysis tool. The description and practical application of these
software tools are discussed in this paper.
33
Constituents' annual load estimation from highways. M. Kayhanian*+; S. Ha; M. K. Stenstrom
Presented by Masoud Kayhanian, University of California at Davis, United States of America
Constituents’ Annual Loads Estimation (CALE) is a program to estimate annual stormwater runoff constituent loads from highways
and their shoulders. It uses Visual Basic for Applications, which is included with ArcGIS Desktop (ESRI, Redlands, CA). The program is
based on the rational method and Event Mean Concentrations (EMCs), which has become a popular method of estimating constituent
loads. The program uses several data sources which are spatially referenced by incorporation into Geographical Information System
(GIS) layers. The program is automated in that the user only needs to select specific watersheds. The watersheds are highlighted by
the GIS application and the constituent loads are presented in tables. Results obtained by CALE showed that the improved area
calculation and the use of regional EMC reduces the estimated load by up to 40% for most constituents over earlier, simpler models.
Experimental investigation of continuous deflective separation for particle fractions transported by rainfall-runoff. J.Y. Kim; S.
Pathapati; S. Ganguly; W. Bartler; J. Sansalone*+
This study examined the event-based performance of continuous deflective separation (CDS) for removal of particle fractions
transported in actual rainfall-runoff from a 1088-m2 source area paved urban watershed. Four independent rainfall-runoff events
were examined and the entire volume of runoff and particulate matter from each event was treated by the continuous deflective
separator at the full-scale treatment facility located on I-10 over City Park Lake in Baton Rouge, Louisiana, USA. Significant removal
(> 90 %) for the sediment size particles (> m) were achieved under event-mean surfaceµ75- overflow rate (< 0.15 cm/sec). Overall
particle removal efficiencies for actual rainfall-runoff particle gradations were generally higher than 45% even at highest hydrologic
loading condition (2.8 cm/sec). Separation performance of the continuous deflective separator is significantly influenced by influent
particle gradation in rainfall-runoff. Such influent particle gradation is strongly influenced by intensity and temporal distribution of
hydrologic loadings during an event.
Parameter study of a flush wave using numerical modelling. N. Kirchheim*+; J. Schaffner; M. Oberlack
Presented by Norma Kirchheim, Hydromechanics and Hydraulics, Technische Universi, Germany
The management of deposits in combined sewers is very important to avoid aquatic pollution. One ecological possiblity to clean
sewers is the use of a flushing device to remobilize deposits. In the past several experimental or one dimensional numerical
investigations were carried out to gain more information on the efficiency of flush waves in sewer channels. This paper presents a
scientific research carried out on a stormwater holding tank. The analysis is based on three dimensional numerical modelling solving
the Navier-Stokes equation extended by the k-e turbulence model. The free surface water-air interaction is handled by the Volume
of Fluid method. Several scenarios for different boundary conditions concerning the flushing device have been tested. To evaluate
the cleaning efficiency it was very important to investigate the shear stresses created by the flush wave. It could be shown that the
influence of the initial condition is less important for long-term purifications. The length of the channel which could be cleaned by a
flush wave depends predominantly on the flushing volume and its ratio to the dam height. According to this investigation flush wave
cleaning is a good alternative for cleaning of a stormwater holding tank of 350 m length compared to classical more etablished
methods.
A 2-layer approach to simultaneously model rainfall runoff events in urban catchments and in their rural surroundings. A.
Klawitter*+; M. Ostrowski
Presented by Arne Klawitter, Technische Universität Darmstadt, Germany
The paper introduces a new modelling approach which aims at an improved flow representa-tion in mesoscale rural catchments with
a high portion of populated area. This approach com-bines two existing models, one distributed GIS-based grid model for rural areas
and one con-ceptual urban pollution load model, which are represented by one model layer each. By defin-ing points of interactions
between the two model layers, discharges of the two models can be interchanged. The model was tested on a theoretical test case,
which demonstrates the model’s improved capabilities to simulate details of system behaviour. Since the results are promising, the
new modelling approach can be a valuable tool for integrated water resources management with respect to the Water Framework
Directive. However, more real world model applications have to be carried out in the near future to further evaluate and validate
the model.
Pollution based real time control of a combined sewer overflow structure. K. Klepiszewski*+
Presented by Kai Klepiszewski, Centre de Recherche Public Henry Tudor, Luxembourg
Real time control processes in combined sewer systems are normally based on measurements of the hydraulic load conditions in the
system. Dependent on the conditions, the flow in the system is adjusted to optimise the utilisation of available storage volume, to
reduce discharged volume and pollutant loads into receiving water courses, and to support the operation of waste water treatment
plants. Moreover, if the focal point of interest is the reduction of emitted pollutant loads the control process can also be based on
the quality of the combined sewage discharged to the receiving water. The presented study describes the development of such a
pollution based real time control application for a combined sewer overflow structure and the simulation of its efficiency. The
objective of the control system is to reduce the flow to a hydraulically overloaded waste water treatment plant by accepting a slight
increase of the pollutant load discharged to the receiving water at the observed structure. The control procedure is based on a
multiple correlation between the spectral absorption coefficient and turbidity, both measured online, with Chemical Oxygen Demand
(COD). The developed pollution based real time control system adjusts the flow pumped to the waste water treatment plant
depending on the COD concentration in the overflow to the receiving water.
IBOS Regenwater: the Dutch interactive decision support tool for sustainable storm water management. J. Kluck*+; P.G.G.
Ganzevles; M.M. van Wijk; A.S. Beenen
Presented by Jeroen Kluck, Tauw bv, Netherlands
In order to facilitate urban water managers developing alternative ways of dealing with storm water, an interactive decision support
system has been developed. It is called “IBOS Regenwater” (Dutch abbreviation for: Interactive Decision Support System for Storm
Water) and can be used on the Internet: http://www.ibosregenwater.nl. The decision support system focuses on local projects. It
results in a well argued policy line for storm water management that is adapted to the specific local conditions. The main
characteristics of IBOS Regenwater are the easy access of GIS-based information and a clear decision support concept, resulting in
only four steps to be taken by the user. IBOS Regenwater supports different ways of obtaining information related to the local
possibilities. It provides access to databases for national legislation, regional policy guidelines, case studies, drainage methods and
BMP’s. The methodology is based on 5 principle mechanisms for dealing with storm water: usage, retention on the surface,
infiltration, discharge to surface water or, as the last option, discharge to a WWTP. The DSS supports the water managers in creating
alternatives. The DSS subsequently assessed the environmental effects and the resources needed to realise and maintain the specific
alternative.
Distribution of heavy metals in freshwater ecosystem of small stream impacted by urban drainage. D. Kominkova*; J. Nabelkova+
Presented by Jana Nabelkova, Czech Technical University in Prague, Czech Republic
This paper is focused on the study of heavy metals remobilisation possibilities and changes of distribution coefficients leading to
remobilization as a result of changing conditions in stream caused by urban drainage. The paper also reports consequent changes of
bioaccumulation coefficient for different species of benthos community, which seems to be the best indicator of aquatic community
quality in small urban streams. The paper presents results obtained during field monitoring as well as results obtained during
laboratory experiment. The field monitoring identified in the study area (the Botič creek) three heavy metals (Cu, Zn, Pb), which are
the main source of toxicological risk in this area. Based on the monitoring, these elements were used for laboratory experiment,
where their behavior during changing conditions was studied. The experiment shows that changing conditions in stream caused by
urban drainage significantly impact the fate of heavy metals in aquatic ecosystems and that these elements have different
preferences to bind to particular geochemical fraction of sediment, which consequently means different bioavailability.
Failure of sewage pumps: statistical modelling and impact assessment. H. Korving*+; M. Geise; F. Clemens
Presented by Hans Korving, Witteveen+Bos, Netherlands
Sewage pumping stations are directly responsible for affecting performance; i.e. failing pumps may result in combined sewer
overflows or flooding. However, failures of sewage pumps are not yet incorporated in sewer assessments due to lack of knowledge
and data. This paper presents the analysis of pump failure data provided by two sewer management authorities in The Netherlands.
Pump failures have been studied accounting for the nature of the failures, the operation and maintenance procedures of the
management authority, the ageing of the pumps and the changes in the environment of pumps. The analysis shows that sewage
pumps fail relatively often due to the composition of sewage and the discontinuous operation of the pumps. The interarrival time
and the duration of failures are highly variable and independent of the pump type and the specific function of the pump. The results
also indicate that the serviceability of sewer systems is significantly affected by failing pumps. As a consequence, part of the
environmental damage due to CSOs (combined sewer overflows) can be avoided by improving maintenance of pumping stations.
Water sanitation management in Tunisia. A. H. Koundi*+
Presented by Abdel Halim Koundi, ONAS, Tunisia
The development of urbanism in Tunisia, the increase of the demand of water of good quality, as well as the expansion of industry
have produced an increase of the quantities of rejected polluted wastewater. Confronted with the danger of the decrease of the
Tunisian water resources the Tunisian government we realized the necessity to preserve and reutilize them, the reason why the
Tunisian government has created in 1975 the "National Office for Sanitation" (O.N.A.S.). "O.NAS" has permitted a rapid development
of wastewater plants. In 1990 Tunisia officially adopted a “polluter pays principle”. These efforts have resulted in an improvement
of quality life and hygienic conditions in the urban areas and have contributed to preserve the citizen’s health conditions and to
protect the environment against water pollutions and contaminations, according to Tunisian standard NT 106-02 (1989) and apart
from the economization of water resources by reutilization of wastewater. The treated water of the wastewater plants is partially
reused (about 24%) according to Tunisian standard NT 106-03 (1989). Reuse and recycling of wastewater are very important for the
development of a well-established management of water and environment. In Tunisia its reuse enters in the national environment
policy.
Innovative tracer methods for infiltration monitoring. O. Kracht*+; M. Gresch; W. Gujer
Presented by Oliver Kracht, EAWAG, Switzerland
Two innovative tracer methods for the quantification of parasitic discharge in sewers have been proposed as routine applications
within the scope of the European research project APUSS (Assessing Infiltration and Exfiltration on the Performance of Urban Sewer
Systems). In order to improve the accuracy of wastewater hydrograph separation compared to conventional practice, the novel
approaches are using intrinsic physicochemical characteristics (stable isotopes, pollutographs) of the wastewater as a natural tracer
for the differentiation of its constituting components. The article analyses the achieved state of development and demonstrates the
application of the protocols with a comparative experimental study.
Radar rainfall time series for the performance assessment of sewer systems. S. Krämer+; H.-R. Verworn*; J. Ziegler
Presented by Stefan Kraemer, University of Hannover, Germany
The performance assessment of sewer systems using historic rainfall time series as input to rainfall runoff models has become an
established practice. The generally used uniformly dis-tributed rainfall does not take into account the effects of spatial variations in
the rainfall pat-terns but is believed to result in rather higher than lower runoff results. The use of distributed rainfall is desirable,
but only now are the time series of radar data starting to get long enough, whereas the otherwise necessary long parallel time series
of neighbouring stations are not available in most cases. For this investigation rainfall data from a network of ground gauges as well
as from a weather radar have been available for a period of nearly seven years. With a series of 33 relevant events rainfall runoff
simulations were carried out using three different types of rainfall information: uniform rainfall using one rain gauge, distributed
rainfall from seven gauges and radar rainfall. For the assessment the calculated areal rainfalls were used as well as the resulting
numbers of surcharged manholes and surcharges per manhole. It is clearly demonstrated that carefully processed radar data can
substitute the rain gauge time se-ries.
Cementitious porous pavement as a passive unit operation for rainfall-runoff control in the built environment. X. Kuang; J.
Sansalone*+; J. Teng; L. Wang; J. Metcalf
Porous pavement is a structural low impact development (LID) material for rainfall-runoff control. In this study, pore characteristics
of t),φcementitious porous pavement (CPP) material, including total porosity ( e), pore size distribution (PSD)pore, and
tortuosityφeffective porosity ( are examined using x-ray tomography (XRT) and conventional )τ( gravimetric-geometric methods. The
methodology and results provide tools when modeling CPP material as an infiltration interface, a conveyance/storage medium for
liquid and gas, a filtration material for particle removal from runoff. Hydraulic conductivity and particle removal efficiency of CPP
material are presented based on experimental measurements. Results indicate that high particle removal efficiencies and high
hydraulic conductivities can be achieved with CPP.
Use of water damage data from damage control enterprises. T. Kunnerup*+; F. Lapertis; N. A. Jensen; B. Laden.
Presented by Tina Kunnerup, NIRAS, Denmark
To obtain more profound knowledge of the municipal sewerage system the Municipality of Aalborg has carried out a registration
project. Data from local damage control enterprises are used for registration of municipally sewered buildings which have been
exposed to sewer surcharge incidents. The project has resulted in profound knowledge of where and to which extent water damages
due to surcharge occur. In Aalborg, the knowledge acquired from the damage control enterprises’ data is used in combination with
computerized hydraulic models (MOUSE) and local rain gaugings. In this way the Municipality obtains improved knowledge of the
functionality of its sewerage system. The Municipality of Aalborg has used the improved knowledge on problematic spots as to sewer
surcharges to target information to citizens regarding sewer surcharge incidents and to give priority to municipal sewer rehabilitation
works. Finally, the actual knowledge of problematic spots has been used in connection with verification of the computerized
hydraulic models used when making hydraulic analyses of the municipal sewerage system.
35
Quantifying the effects of sedimentation and remobilization of solids in a CSO wetland. R. Kutzner*+; W.F. Geiger
Presented by Ralf Kutzner, University of Duisburg-Essen, Germany
For facilities for the treatment of wet weather flows regarding to standards based on the immission approach a very detailed
knowledge about the removal efficiency is necessary. One of the relevant parameters to characterize the matter loads discharged to
the receiving water is Total Suspended Solids (TSS). Because of that, the TSS treatment efficiency of a surface flow wetland was
researched for more than one decade. In the first instance it seemed to be possible to model the TSS-removal by a simple two
parameter first order decay function. But enhanced validation showed that this is not possible. By analysing time series of settling
velocity distribution it was possible to quantify the effect of sedimentation, adsorption and remobilization to the removal of several
sinking velocity fractions. This could be the basis for the optimization of these kind of structures and for the development of more
sophisticated mathematical models.
Optimizing the operation of large interceptor systems. J. Lamarre*+; D. D. T. Duong; A. Charon; H. Colas
Presented by Jean Lamarre, BPR CSO, Canada
The operation of large interceptor systems is complex. In most systems, static regulators are used to limit inflows into interception
system and ensure that treatment plant capacity is never exceeded. Full capacity is then hardly ever used and the system still
overflows often. To capture more flow, especially in recurrent wet weather, interception may be regulated by dynamic regulators.
Regulating these structures according to water levels in the interceptors may yield significant performance improvements but it
doesn’t help operators figure how much flow will reach the plant and when. Hence, we may provide operators with decision support
tools that will predict and regulate flows according to current and available plant and pump station capacities, wastewater
treatment plant (WWTP) configuration, control devices and equipment status, and size and extent of wet weather events. The City
of Montreal is finishing the upgrade of its local reactive Real-Time Control system to a global optimal RTC (GO RTC) system with
radar rainfall predictive capabilities. The system optimizes regulated flows in the interceptors and to the WWTP during wet weather.
This paper covers the system architecture, the expert system main modules, the field equipment needs, the main steps of
implementation, and initial operational results.
The city of Montreal's overflow control program. J. Lamarre*+; D. D. T. Duong; A. Charron; H. Colas
Presented by Jean Lamarre, BPR CSO, Canada
The Quebec provincial government (Ministère de l’Environnement du Québec) has defined environmental discharge objectives (EDO)
to protect receiving water bodies and their use against CSOs, SSOs and storm water pollution. The objectives have been established
on the basis of direct and indirect water uses, which are to be protected or rehabilitated. They have been defined in terms of
maximum overflow frequencies per area and based on the uses of the receiving water bodies. The City of Montreal is committed to
the implementation of a program to control the overflows from the island’s combined sewers in order to comply with the objectives
and to rehabilitate the St. Lawrence River and of the Rivière des Prairies. Six solution scenarios in as many intervention programs are
presented and evaluated, from the simplest to the more complex. This document presents the environmental objectives with regard
to discharge in both media and based on the long-term, as well as the intervention scenarios to reach these goals. The assessment is
based on environmental and financial criteria, as well as implementation and operation criteria.
Interactions within wastewater systems. J.G. Langeveld*+; F.H.L.R. Clemens; J.H.J.M. van der Graaf
Presented by Jeroen Langeveld, Royal Haskoning, Netherlands
Wastewater systems consist of sewer systems and wastewater treatment works. As the performance of a wastewater treatment plant
is affected by the characteristics, i.e. operation and design, of the contributing sewer systems, knowledge of the interactions
between sewers and wastewater treatment works is very important when trying to understand and improve wastewater systems. This
paper presents an overview of the results of a 4 year research project studying the interactions within wastewater systems, focussing
on three topics. At first, the sensitivity of wastewater treatment plant performance to influent fluctuations is discussed, based on
both measurement data and model results. Secondly, the quality of model results achievable with state of the art sewer models are
described for the most important in sewer processes. Finally, the impact of the interactions within the wastewater system on
wastewater system performance is illustrated in a semi-hypothetical case study. The paper concludes that knowledge on the
interactions is not only essential with respect to understanding of wastewater system performance, but that this knowledge opens
new ways of dealing with our existing wastewater infrastructure.
Designing BMPs considering water quality criteria. T. Larm*+
Presented by Thomas Larm, SWECO INTERNATIONAL, Sweden
We require to have a better understanding of whether the designed or constructed Best Management Practices (BMPs) are costeffective and have the desired effects on the receiving waters or if complementary or alternative measures are needed. The
operative Excel model StormTac integrates watershed, transport, recipient and BMP processes. The aim is to present the key
equations and parameters. Complementary studies and uncertainties are briefly discussed. StormTac has been implemented in many
case projects for planning-level studies with a small amount of input data, as well as for detailed design considering the impacts on
the recipients. The uncertainty studies have identified some parameter values, their ranges and processes to be changed, e.g. the
base flow equations. Further studies will be performed especially regarding uncertainty estimations and by adding pollutant
concentration data to decrease uncertainty and reflect time trends. Obligatory required input data are area per land use, water
volume and mean water area of the recipient. Examples of parameters for which default data can be used or overwritten are
precipitation intensity, land use specific runoff coefficients and storm water pollutant concentrations, measured and critical
pollutant concentrations in the water of the recipient and average daily traffic intensity for larger roads.
Facilitated transport of metals and bacteria into two infiltration basins in Lyon (France) under changing hydrological conditions:
soil column study. H. Larmet*+; C. Delolme; J.-P. Bedell; M. Neto
Presented by Hélène Larmet, ENTPE, France
The surface of infiltration basins, used to discharge urban stormwater, is an overpolluted matrix containing many reactive
compounds liable to facilitate the transfer of heavy metals through the vadose zone to the aquifer. In the two basins studied, the
metallic content is high (970 ppm of Zn and 5.23 ppm of Cd) and the organic matter and the bacteria are very abundant (5.56E+09 to
1.23E+10 bacteria/g of dry soil), by opposition to those of the unpolluted underlying soil ; the granulometric analysis also underscore
the numerical importance of colloids and aggregates in the topsoils. Instability tests and leaching tests in small columns complete
the study and the evaluation of potential behaviour of the surface soils and their components. Instability tests establish that Zn has
big affinities with the organic matter and with the colloidal compartment, while Cd remains in the aggregates. In columns where
rainfalls close to real hydrodynamic conditions are simulated, the first pore volume water eluted is distinguished by high contents on
metals and bacteria, but the alternance of wetting/drying phases is attended to largely influence the fate of this two compartments.
To complete ultra- and microfiltration, coupling MEB and X-fluorescence is foreseen to investigate their potential bonds.
Computational and experimental study of velocity profiles in sewers. F. Larrarte*+; J. B. Bardiaux; H. Bonakdari
Presented by Frédérique Larrarte, Laboratoire Central des Ponts et Chaussées, France
Sound management of sewer networks and minimization of the pollution discharged into receiving waters through combined sewer
overflows need in-depth knowledge of the flow rates and pollutant loads conveyed in sewers. A precise knowledge of the pollutant
discharge relies on a good assessment of the spatial distribution of the velocities in a cross section, as they are involved both in
flowrate, and distribution of concentration. Our research teams are studying the representativeness of velocity profiles in real
sewers by using experimental and numerical tools. This paper presents the experimental site and results before explaining the
numerical study that is in progress and comparing the experimental and numerical results.
Water quality criteria guiding the selection and design of stormwater management measures. A. I. Lawrence*+; B. C. Phillips+
Presented by Ian Lawrence, CRC FOR FRESHWATER ECOLOGY, Australia
Effective protection and management of aquatic ecosystems and other water resource values requires the establishment of clear
links between catchment land use and management practice and receiving water quality. This paper demonstrates an approach to
translate the receiving water protection objectives (water quality guidelines) to sustainable catchment loads of key pollutants or
stressors. By comparing these values with assessments of current and projected future loads it is possible to identify the pollutant or
stressor reduction targets that need to be addressed in land use and stormwater management measures. This approach is consistent
with the risk based management approach and assessment process identified in the ANZECC/ARMCANZ Guidelines for Fresh and
Marine Water Quality 2000. Applying this approach, the paper develops performance criteria (sustainable catchment loads) against
which the selection and design of management measures can proceed in an effective and efficient manner. This approach has been
adopted in the draft “Australian Runoff Quality Guidelines ” released buy Engineers Australia in June 2003. It is concluded that this
approach provides a basis for linking performance requirements for urban stormwater management practices to receiving water
quality. It also provides a model for other countries who are preparing national guidelines for the protection of sensitive receiving
waters from the impact of land use change.
Life cycle optimization for highway BMPs. J. G. Lee; J. P. Heaney*+; D. N. Rapp; C. A. Pack
Presented by James Heaney, University of Florida, United States of America
Highway runoff can cause a number of water quantity and quality problems. Stormwater management systems for highways have
been developed based on a fast drainage for large storm situations. Nonpoint source pollution from highway runoff is a growing water
quality concern. Stormwater quality control needs to be integrated into highway drainage design and operation to reduce the
stormwater impacts on the receiving water. A continuous simulation/optimization model for analyzing integrated highway BMPs is
presented. This model can evaluate the life cycle performance of infiltration and/or storage oriented highway BMPs. It can be
directly integrated with spreadsheet optimization tools to find the least cost options for implementing BMPs throughout a specified
life cycle.
Characteristics of washed-off pollutants and dynamic EMCs in a parking lot and a bridge during storms. K. Lee-Hyung*+; K. Lim;
S. Ko
Presented by Lee-Hyung Kim, Kongju National University, Republic of Korea
Since the water quality has been recognized as a big issue in drinking water sources, the Ministry of Environment, Korea, are
designing the TMDL program for major large rivers. In order to settle the TMDL program successfully, nonpoint pollutants causing
from various landuses should be controlled. Especially paved areas such as parking lots and bridges are stormwater intensive landuses
because of high imperviousness and high pollutant mass emissions from vehicular activity. Vehicle emissions from these paved areas
include different pollutants such as heavy metals, oil and grease and particulates. Therefore, this research has been conducted to
understand the magnitude and nature of the stormwater emissions with the goal of quantifying stormwater pollutant concentrations
and mass emission rates from a parking lot and a bridge. Two monitoring sites in Kongju city were equipped with an automatic
rainfall gauge and an automatic flow meter for measuring rainfall, water quality and runoff flow. This manuscript will summarize the
concentration changes during storm duration and EMCs in a parking lot and a bridge. The first flush criteria will be also suggested
using dynamic EMCs. It is a new concept explaining the relationship of the EMC and first flush effect.
Field monitoring and evaluation of the stormwater management StormFilter® in the State of Washington. J. H. Lenhart*+; S. de
Ridder
Presented by James Lenhart, Stormwater Management, Inc, United States of America
In 2003 the Washington State Department of Ecology adopted new criteria defining a design storm and expected BMP removal
performance. Ecology also formed a Technical Review Committee (TRC) to establish a protocol for evaluating BMPs, which became
known as the “Technology Acceptance Protocol—Ecology” (TAPE). To gain approval a manufacturer prepares an application including
a technology description, maintenance and cost information, laboratory and field data. Based on this application the TRC gives a
designation. Technologies receiving Pilot Level Designation (PLD) or Conditional Use Designation (CUD) must implement a study to
gain the General Use Level Designation (GULD). The study is designed according to the TAPE including a Quality Assurance Project
Plan (QAPP) and the selection of a project evaluator who assures data integrity. In 2002, the StormFilter gained the CUD. A QAPP was
then developed and implemented in early 2003. In June 2004 sampling was competed and final reports were submitted to Ecology.
The results showed statistically significant reduction of TSS to a mean effluent concentration of 19 mg/l for influent concentrations
less than 100 mg/l and an 80% or greater removal of TSS for influent concentrations greater than 100 mg/l. GULD for the StormFilter
was granted in January 2005.
One-dimensional GIS-based model compared to two-dimensional model in urban floods simulation. J. Lhomme*+; C. Bouvier; E.
Mignot; A. Paquier
Presented by Julien Lhomme, Université Montpellier 2, France
A GIS-based one-dimensional flood simulation model is presented and applied to the centre of the city of Nîmes (Gard, France), for
mapping flow depths or velocities in the streets network. The geometry of the one-dimensional elements is derived from the Digital
Elevation Model (DEM). The flow is routed from one element to the next using the kinematic wave approximation. At the crossroads,
the flows in the downstream branches are computed using a conceptual scheme. This scheme was prior designed to fit Y-shaped
pipes junctions, and has been here modified to fit X-shaped crossroads. The results were compared with the results of a twodimensional hydrodynamic model based on the full shallow water equations. The comparison shows that good agreements can be
found in the steepest streets of the study zone, but differences may be important in the other streets. Some reasons that can explain
the differences between the two models are given and some research possibilities are proposed.
Integrated modelling of two xenobiotic organic compounds. E. Lindblom*+; K. V. Gernaey; M. Henze; P. S. Mikkelsen
Presented by Erik Lindblom, Technical University of Denmark, Denmark
This paper presents a dynamic mathematical model that describes the fate and transport of two selected xenobiotic organic
compounds (XOCs) in a simplified representation of an integrated urban wastewater system. A simulation study, where the
xenobiotics bisphenol A and pyrene are used as reference compounds, is carried out. Sorption and specific biological degradation
processes are integrated with standardised water process models to model the fate of both compounds. Simulated mass flows of the
37
two compounds during one dry weather day and one wet weather day are compared for realistic influent flow rate and concentration
profiles. The wet weather day induces resuspension of stored sediments, which increases the pollutant load on the downstream
system. The potential of the model to elucidate important phenomena related to origin and fate of the model compounds is
demonstrated.
Use of 3D modeling to instrument CSOs. G. Lipeme Kouyi+; J. Vazquez*; Y. Simonin; M. Zug; J.B. Poulet
Presented by Gislain Lipeme Kouyi, ENGEES, France
The assessment of the flows and the pollutant load discharged into the natural environment requires the installation of an adequate
instrumentation. The knowledge of the hydraulic operation of the Combined Sewer Overflows (CSOs) is thus essential. We use 3D
modeling (FLUENT) in order to understand the hydrodynamics in these works. Initially, the numerical results arising from 3D
modeling of the flows in side storm overflows were validated in experiments in laboratory. In the second time, we applied the 3D
modeling to the CSO of Clichy (France). Simulations enabled us to know the various shapes of water lines and the evolution of the
overflow rate along the weir. The location of the free surface was done by means of VOF method. The analysis of the results of
simulation was enabled to improve the instrumentation of this CSO.
Integrated urban and rural water management using modern meteorological data. A. H. Lobbrecht+; S. J. van Andel*
Presented by Arnold Lobbrecht, UNESCO-IHE and HydroLogic, Netherlands
This paper describes applications of modern meteorological data for water management in urbanised areas. A case study for the city
of Rotterdam (NL) is presented. It is stated that integrated water management in urbanised areas should include another dimension
by integrating operational water management of urban and rural areas. The use of modern precipitation radar contributes to this
goal. The Royal Dutch Meteorological Institute (KNMI) delivers operational radar data to municipalities and waterboards these days.
The data consists of 24-hours and 3-hours precipitation sums. Precipitation-radar data for the region of Rotterdam shows a high
degree of spatial variability that cannot be captured by the point measurements of available groundstations. Differences in
precipitation depth per sewer district amount to 10 mm and more. The radar data can be used to improve calibration of rainfall
runoff based computational models. This leads to better understanding of passed events and system responses, better modelling of
rainfall runoff processes and enhanced system design. Moreover, real-time control can be implemented on the basis of these data,
using spatial variability in precipitation during the event. Further research will explore innovative operational management
strategies, such as redistribution of water to prevent flooding and control of combined sewer overflow locations in cooperation
between urban and rural water authorities.
On detecting gas pockets in pressurised wastewater mains. C. Lubbers*+; F. Clemens
Presented by Christof Lubbers, Delft University of Technology, Netherlands
In the Netherlands, wastewater is mostly collected in combined sewer system and transported to a WWTP through pressure mains.
These pressure mains form an element of the system that did not receive much attention lately with respect to monitoring of
performance and maintenance. Failure of operation is only noticed when during storm conditions the capacity of the system drops,
resulting in undesirable discharge to the surface water. A recently made inventory showed that about half of the pressure mains in
the Netherlands show increased pressure loss for no obvious reason. Reduction of the systems nominal capacity can result from many
causes, like increased wall roughness, scaling and the occurrence of free gas in the pipeline. The occurrence of gas-pockets may be
caused by degassing of dissolved gas, but also by air entrainment at the pump inlet or at air valves. A research project is started to
investigate the above problems. The project focuses amongst other subjects on developing a method to detect and diagnose gas
problems The project is carried out by the University of Delft and Delft Hydraulics in collaboration with the majority of the water
boards in the Netherlands. For this part of the study an experimental facility is constructed having a length of 630 m. This paper
describes the layout of the experimental set-up to detect and diagnose gas problems.
GREEN TECHNOLOGY, Delaware’s urban runoff management approach. W.C. Lucas*+
Presented by William Lucas, Integrated Land Management, Inc., United States of America
It is well recognized that the best approach to mitigate watershed impacts of urbanization is to develop runoff management
practices that focus on retaining rainfall where it lands. This is a fundamental benefit of Low Impact Design (LID). Recent studies
have shown that reductions in runoff volumes, peak flows, and pollutant loads using LID techniques can be substantial. Delaware’s
Urban Runoff Management Approach to LID is a type of “Green Technology” (Lucas, 2004a). It is “Green” since it relies on vegetative
BMPs instead of traditional detention ponds; and it is a “Technology”, based upon physically-based processes, instead of a simple
rule-of-thumb approach. Green Technology BMPs include biofiltration swales, terraces, filter strips and bioretention, as well as
infiltration trenches. This paper briefly summarizes elements involved in Green Technology, and presents how it can be improved
with an innovative infiltration approach.
Distribution of phosphorus for particulate. J. Ma; J. Sansalone*+, P. Veltri
Urban rainfall-runoff transports loads of particulate matter and total phosphorus (TP) from a variety of anthropogenic activities.
Discharge of diffuse sources of phosphorus as a leading cause of receiving water eutrophication has received significant attention.
Elevated phosphorus concentrations in rainfall-runoff have been commonly identified for many urban land uses. In some cases these
phosphorus concentrations can approach levels of untreated wastewater plant influent. Particulate matter is also entrained with
phosphorus in urban rainfall-runoff and this particulate matter encompasses a m). While particulate matter can beµwide particle size
gradation (1 ~ 4750 m, this size range encompasses theµm and larger than 4750 µsmaller than 1 suspended, settleable and sediment
fractions of particles. Though a variety of mechanisms the transport, fate and treatment of phosphorus is influenced by the physicochemical properties and loading of particulate matter. The knowledge of particulate-bound total phosphorus (TP) distribution across
the particulate size gradation can be used to assess removal and loading of phosphorus as a function of granulometric mass and
design unit operations and processes (UOPs) targeting phosphorus associated with a particle gradation. This study investigated
particulate-bound total phosphorus (TP) distribution from a series of rainfall-runoff events. The results indicate that particulatebound TP and particulate matter mass follow similar distributions on an event basis and across a size gradation. In addition, results
confirm that particulate-bound TP distributes across the entire particle size gradation. Particle gradations with larger total surface
areas, under equal residence times and chemistry, generally have higher total phosphorus mass.
Assessment criteria for a sustainable management of the water resources. M. Maiolo*+; G. Martirano; P. Morrone; D. Pantusa
Presented by Mario Maiolo, Università della Calabria, Italy
The present work describes the in-progress activities devoted to the definition of a model of sustainable management of the water
resources at local scale, with special reference to an Optimal Territorial Ambit (ATO). These activities partly take as a starting point
the EPSILON international research project “Environmental Policy via Sustainability Indicators On a European-wide NUTS-III level”.
The objective of such a model is to overcome the current DPSIR (Driving force-Pressure-State-Impact-Response) approach, allowing
to create an ISST (Sustainability Synthetic Territorial Index), which is a composite indicator obtained from elementary indicators of
environmental, economic, social and institutional nature, subsequently aggregated in sub-themes, themes and pillars. The 155
Municipalities constituting the ATO can then be clustered in 5 categories (very low, low, middle, high, very high), according to the
value of the corresponding composite sustainability indicator. Thanks to this approach, several classes of users can simulate different
sustainability scenarios relevant to different values of the elementary indicators. In particular, the identification of sustainability
indicators for the management of water resources allows a quick assessment of the management actions to be activated for the
water use and reuse, with reference to the different uses and the different aspects of the Integrated Water System.
Decision support framework for sustainable urban water planning and management in new urban areas. C. Makropoulos*+; M.
Morley; F. Memon; D. Butler; D. Savic; R. A. Ashley
Presented by Christos Makropoulos, Imperial College London, United Kingdom (Great Britain)
The paper discusses issues of decision support within the context of sustainable development and more specifically sustainable water
cycle management to provide a context and a rationale for the decision support approach adopted within an on-going UK EPSRC
funded project: WaND. The paper proposes a set up for a flexible, upgradeable, efficient and modular decision support framework
and associated tools. Furthermore, the paper presents early prototypes of three decision support tools developed within the
proposed framework including initial results for one of them.
Influence of the new European Directives on the urban drainage system. P. Malgrat; A. Villanueva; D. Suñer*+
Presented by David Sunyer, CLABSA, Spain
The new European Directives which concern water issues that have been developed in the last years, have them all some common
goals, which can be summarized in: · Promote a gradual improvement in water quality of the drainage bodies. · Integral management
of the whole urban water cycle, involving all the organizations with competences and responsibilities in the subject and increasing
the participation in the decision making process. · Increase the transparency in management, informing the citizens about receiving
bodies’ water quality, and especially about the bathing water quality due to its influence to public health. This new concept applied
to the urban drainage management will mean a need to improve the sewerage systems management in all the stages: planning,
project and works, operation, and finally maintenance. For a correct implementation of these new directives and the actions derived
from them, it will be necessary to define responsibilities and to provide the necessary economic resources to put them into practice.
It will be necessary to increase national and local water taxes to finance the new works.
Modelling sewer network behaviour using artificial neural networks. G. Manic*+; F. Gogien; M. Zug
Presented by Gildas Manic, Anjou Recherche / Veolia Water, France
Forecasting the behaviour of sewer networks has become a priority to better understand and anticipate the hydraulic and the
pollution load depending on meteorological events, in order to anticipate the impact of both the treated part of the polluted WWTP
inflow and untreated sewerage through the CSO’s into the natural environment. This is especially critical for seaside cities because
of the quality of the bathing water. An existing “white-box” model using the Infoworks© CS software has been built for several cities
and provides satisfying results in term of hydraulic and pollution forecasts. This article presents a “grey box”-type model using the
artificial neural networks and a “light” physical model. It has been developed to simulate the hydraulic and also pollutant loads at
the outlet of elementary catchment groups, where no downstream influence has been noted and no ancillaries are real time
controlled. The results were compared with empirical data coming from measurement campaigns. This approach cannot reach the
accuracy of a “white box” model (especially for specific influence or RTC) but has the advantages to be licence-free, easy to put in
place, give a robust, acceptable simulation and to carry out very fast simulations.
Integrated urban water modeling with uncertainty analysis. G. Mannina*+; G. Freni; G. Viviani; S. Sægrov; L. S. Hafskjol
Presented by Giorgio Mannina, Università di Palermo, Italy
In the last 20th years, the scientific world has got particular care towards the problems that involve the respect of the environment.
According to this point, several researches were developed to describe the phenomena that take place during both wet and dry
period and to increase the knowledge in this field. In particular, the attention was addressed towards the problems linked with the
pollution of the water body because of the pollution carried by rainfall waters in the urban environment. In order to obtain a good
description of the problem, it is important, of course, to analyze both quantity and quality aspects connected with all the
transformation phases that characterize the urban water cycle. Today, according to this point, integrated modelling approach is
spreading aiming to find solutions to improve the quality characteristics of the receiving water body. Because several models are
connected together for analyzing the fate of pollutants from the sources on the urban catchment to the final recipient, classical
problems connected with the selection and calibration of parameters are amplified by the complexity of the modelling approach
increasing the uncertainty and the reliability connected with models application.
An elutriation apparatus for assessing settleability of combined sewer overflows (CSOs). J. Marsalek*+; B.G. Krishnappan; K.
Exall; Q. Rochfort; R.P. Stephens
Presented by Jiri Marsalek, National Water Research Institute, Canada
An elutriation apparatus was proposed for testing the settleability of CSOs and applied to 12 CSO samples. In this apparatus, solids
settling is measured under dynamic conditions created by flow through a series of settling chambers of varying diameters and upward
flow velocities. Such a procedure reproduces better turbulent settling in CSO tanks than the conventional settling columns, and
facilitates testing coagulant additions under dynamic conditions. Among the limitations, one could name the relatively large size of
the apparatus and samples (60 L), and inadequate handling of floatables. Settleability results obtained for the elutriation apparatus
and a conventional settling column indicate large inter-event variation in CSO settleability. Under such circumstances, settling tanks
need to be designed for “average” conditions and, within some limits, the differences in test results produced by various
settleability testing apparatuses and procedures may be acceptable. Further development of the elutriation apparatus is under way,
focusing on reducing flow velocities in the tubing connecting settling chambers and reducing the number of settling chambers
employed. The first measure would reduce the risk of floc breakage in the connecting tubing and the second one would reduce the
required sample size.
Experience feedback on best management practices for urban stormwater drainage: An assessment of their performance and
perception. C. Martin; Y. Ruperd; M. Jauner; M. Legret*+
Presented by Michel Legret, LCPC, France
Reliance upon "Best Management Practices" (BMPs) is becoming increasingly widespread in the field of stormwater source control.
The main objective inherent in the use of such stormwater solutions is to prevent against flooding and sanitary problems within
urban areas. A wide array of stormwater source control solutions exists, and the choice of one versus another often depends on a
large number of criteria related to the hydraulic, technical, environmental, operations & maintenance, social and economic aspects.
A national survey was sent to all potential BMP users in order to assess their perception of such stormwater facilities. This paper
presents the results from the analysis conducted on this survey. The main justification behind BMP use is not economicallymotivated, but rather for flood prevention reasons, whereas the main justification for avoidance of BMP use lies in the adequacy of
conventional sewer systems. Moreover, hydraulic and technical aspects were rated highest by BMP users, while operations &
maintenance aspects received the lowest scores. A large amount of information has been obtained from this national survey; these
data will be incorporated into a decision-aid tool, whose aim is to guide the BMP user in selecting one stormwater solution over
another.
39
Stormwater extension officers in New South Wales, Australia. G. Mashiah*+; M. Sharpin
The New South Wales Stormwater Extension Officer (SEO) program funded nine positions with the objective of improving local
government’s technical and organisational knowledge and skills in stormwater management. The purpose of the SEOs was to guide,
assist and coordinate local government in management of urban stormwater through capacity building. Following needs assessment
and analysis, a targeted capacity building program was undertaken. While generally meeting its objective, the short 30 month
duration of the program limited its ability to promote long term organisational change. Two of the nine regions served have provided
funding to continue the program with a wider focus than urban stormwater.
The stormwater ambassador program - A community education partnership between schools and local government. G.
Mashiah*+; H. TyasTunggal
The Stormwater Ambassador program is an environmental education partnership between schools and local government which
supports students selected by their schools as “ambassadors” to promote stormwater and water cycle awareness within the
community. Ambassadors learn about the catchment which they live in and related water issues during workshops held each school
term, and then develop and implement ideas promoting community awareness. Ambassadors’ activities have included regular
newspaper columns and community newsletters, school assembly presentations, drain stenciling, presenting the Runoffski family
skit, creating community water awareness murals and totem poles. Ambassador students have also undertaken a variety of special
focus campaigns including “Butt Out”, “Say NO to plastic Be calico fantastic” and “Your dog’s business is your business”. Regular and
widespread media coverage of the program also promotes community stormwater awareness. A compact disc resource containing
sample communication material, workshop programs, educational activities, outcomes and evaluations, examples of community
awareness activities undertaken by previous ambassador programs and a professionally produced video has been developed to assist
implementation of the program. This resource has been developed from six separate ambassador programs involving over fifty
schools, and the educational concepts and processes of the program are easily transferable to other environmental issues.
Seasonal flood frequency analysis based on disaggregated urban runoff data. B. V. Matheussen*+; S. T. Thorolfsson; D. P.
Lettenmaier
Presented by Bernt Viggo Matheussen, NTNU, SINTEF Energy Research, Norway
Current design procedures for urban drainage systems are based on the assumption that it is short duration summer rainfall that
produces the highest annual runoff peaks. Despite this several researchers report that in cold climates urban flooding may also
happen as a consequence of rain in combination with snowmelt. Because of this we chose to question the assumption of rainfall
being the only factor controlling urban flooding in cold climates like in Trondheim, Norway. Through a combination of hydrological
modelling and a temporal disaggregation method a time series of hourly runoff data (1946-2003) are generated for the Risvollan
urban catchment in Trondheim, Norway. The hourly runoff data are then used to generate flood frequency curves (FFC) for the
whole year and the summer (May-Oct) period only. The results showed that a FFC based on hourly urban runoff data for the whole
year has a higher 10 year flood than a FFC generated from only summer data. This implies that urban drainage design methods used
for cold climates, similar to Trondheim, should consider all seasons in the design procedure.
Estimation of water level in the trunk sewer during drainage pump operation support (RTC) in wet weather. R. Matsumoto*+; T.
Nishiyama; S. Mushika; S. Morita
Presented by Ryoichi Matsumoto, CTI Engineering Co.,Ltd, Japan
The water levels in wet weather were compared in the Tosabori/Tsumori trunk sewer and at the Tsumori pumping station, which
were being constructed in Osaka, a big city in Japan. The comparison was made through simulations using integrated management
software systems such as MOUSE, SWMM and Info-Works and hydraulic model tests. As a result, the water level of open channel flow
estimated in simulation was higher than that obtained in the test. The variance was less than 6.3% of the diameter of the trunk
sewer. Thus, it was shown that the accuracy and reliability of water level estimation could be nearly ensured. It was also indicated
that estimating the water level at a given point by simulation was difficult where open channel flow changed into pipe flow in the
trunk sewer, where the pumping station was of special shape or where flow was greatly blocked in the trunk sewer by a high head
manhole receiving large discharge of inflow.
Potential future changes in heavy rainfall events in Europe simulated by the HIRHAM regional climate model. W. May*+; B. O.
Christensen; J. H. Christensen
Presented by Wilhelm May, Danish Meteorological Institute, Denmark
In this study potential future changes in the characteristics of daily rainfall events, in particular of heavy rainfall events, in Europe
as a consequence of the anticipated future increase in the atmospheric greenhouse gas concentrations is investigated. This is done
on the basis of a mini-ensemble of simulations for the recent and the future climate with the HIRHAM RCM. HIRHAM simulates
pronounced decreases in the number of wet days in all but northern Europe, in particular in the warm season. The corresponding
changes in the intensity of daily rainfall are not as pronounced, although they show a similar behaviour with a reduction or relatively
small enhancement in summer. The changes in the intensity of heavy rainfall events are generally stronger than for the average
intensity and may be of a different character with more (less) intense heavy rainfall events in areas where the average intensity of
daily rainfall events is reduced (enhanced). The mini-ensemble approach markedly reduces the level of uncertainty from internal
variability when considering the extreme daily rainfall events.
A multidisciplinary approach to stormwater management at the watershed scale. A. L. Mayer*+; A. H. Roy+; W. D. Shuster; H. W.
Thurston; M. P. Clagett; P. K. Parikh; M. A. Taylor
Presented by Allison Roy, U.S. Environmental Protection Agency, United States of America
Stormwater runoff from extensive impervious surfaces in urban and suburban areas has led to human safety risks and stream
ecosystem impairment, triggering an interest in watershed-scale retrofit stormwater management. Such stormwater management is
of multidisciplinary relevance, posing legal, social, economic, hydrologic, and ecological challenges and constraints. A
multidisciplinary approach to stormwater management is being tested in the Shepherd Creek watershed, a 20 km^2 residential and
forested watershed in Cincinnati, OH (USA). An assessment of the total impervious area (TIA) revealed that a majority (50–72%) of
TIA in sub-watersheds is in rooftops and driveways, so we decided to use parcel-level best management practices (BMPs) in the form
of rain barrels and rain gardens to mitigate stormwater runoff. To abide by laws concerning stormwater, a voluntary economic
auction approach will be used to distribute BMPs and evaluate landowners’ willingness-to-accept BMPs on their property in exchange
for financial compensation. The hydrologic and ecologic responses to retrofit stormwater BMPs will be tested using a before-aftercontrol-impact design, where the “impact” is the installation of BMPs. This research suggests a policy prescription for retrofit
management of stormwater quantity that is, if not ideal in one discipline, at least sound in all disciplines.
Study on effects for improvement of wet-weather overflow taking account of the behavior of pollutant load in pumping stations
in combined sewer systems. T. Meguro*+; T. Yamazaki
Presented by Toru Meguro, Environment Planning Bureau, City of Yokohama, Japan
In pumping stations in combined sewer systems, pollutants accumulate in stormwater grit chambers and wet wells. They can be
stirred up and discharged when stormwater pumps are started, and consequently cause pollution in public water areas. An analysis of
the behavior of pollutant load in pumping stations is required for accurate assessment of the pollution situation in receiving water
areas and measures for improvement of such systems. The study team proposed a simulation (box) model for analysis of the behavior
of load accumulated in pumping stations. Besides checking this model against actual data, they also made a quantitative assessment
of the (load-reducing) effect of installation of stormwater tanks and drying of pumping station grit chambers and wet wells. The
simulation results showed a good correspondence between the calculated and actual values for water quality. As for accumulation
quantity, the model also made a good reproduction of the traction of deposits upon activation of pumps. Simulation for a year found
that, relative to the case of no action, the yearly direct discharge SS load could be reduced by 26 percent by drying the grit
chambers and wet wells and 85 percent by the combination of drying and stormwater tank installation.
The Portuguese experience on the regulation of the water and solid wastes sectors - Quality of service assessment. J. Melo
Baptista*; H. Alegre; R. Matos+; E. Beja Neves
Presented by Rafaela Matos, LNEC, Portugal
The main objectives of this paper are to provide an overview of the Portuguese Regulator’s (IRAR) main strategic guidelines and to
describe the outcome of a project carried out, in association with LNEC, aimed at defining the performance indicators (PI) systems
to be used as basis for comparison of the operators’ performance. Three groups of PI were defined, related to: 1) protection of the
user interests; 2) sustainability of the operator; and 3) environmental sustainability. Twenty PI have been set for every type of
service: water supply, wastewater and solid wastes. These PI systems are a fundamental tool for IRAR to implement the quality of
service regulation, as an essential component of its regulatory model. The quality of service regulation frames the operators
performance as far as the quality of service provided to users is concerned and shall not be dissociated from the economic
regulation. At present, the consolidation of regulation is crucial envisaging the enhancement of the current quality of service to the
users. IRAR aims at having a leverage effect in the transition of the country from the current stage of infrastructural investment in
new assets to a new stage of stability and high quality of service delivery.
Effect of rainfall hyetograph on pollutant loads in an urban catchment area. K. Michiokui*+; N. Wada; Y. Tsuji
Presented by Kohji Michioku, Kobe University, Japan
Field measurements and runoff analysis of stormwater in a small urban area were performed. The effects of rainfall hyetograph on
the pollutant runoff process were examined. Excellent agreement between SWMM simulation and field data were found not only with
the runoff discharge, but also with the concentration and washoff rate of nutrients. A response analysis of pollutant runoff was
carried out for design storms of single-peaked triangular hyetographs with various durations and peak intensities. The results provide
information useful in the management of sewage and river systems, such as in the design and operation of sewage treatment plants,
planning of river restoration for increasing river self-purification capability, scheduling of road cleaning operations, land use
planning, etc.
Practical measurement of stormwater events – Not a trivial task. T. Mietzel*; T. Frehmann+; R. Kutzner; M. Becker; W.F. Geiger
Presented by Torsten Frehmann, Emschergenossenschaft, Germany
Setting up and maintaining monitoring stations is a common, but not trivial task for engineers working in the field of urban water
management. Especially when faced with this task for the first time, it is difficult to find applied literature that gives answers to
common problems with measuring equipment. The experience gathered during three major studies at stormwater treatment
facilities, is summarized in this paper. The measuring included level measurement and flow measurement with different methods as
well as quality measurement with automated samplers. Problems are highlighted and recommendations for installation are given. At
all three monitoring stations in , out , and overflows were monitored, giving the chance to state errors on the bases of a closed
balance.
Flow structure at the junction of four supercritical channel flows. E. Mignot*+; N. Riviere; R. Perkins; A. Paquier
Presented by Emmanuel Mignot, Cemagref, France
Supercritical flow in a 4 branch channel intersection has been studied theoretically, experimentally and numerically. The flow
configuration investigated here consists of one oblique jump in the junction and one normal jump in an upstream branch, along with
a deflection line, one eddying zone and two recirculation zones. The water depths have been measured rather precisely at 580 points
in the junction, to provide a data base for testing theoretical and numerical models. We develop an analytical model based on the
momentum equation, which predicts the angle of the oblique jump and the deflection angle for the flow. The predictions are in
reasonable agreement with the experimental data. The flow being well known, the capacities of a 2D model to simulate this flow are
tested. It appears that the computed flow structures are similar to the observed flow features even though some discrepancies
appear concerning the shapes of these structures.
Comparison of numerical and experimental simulations of a flood in a dense urban area. E. Mignot*+; A. Paquier; T. Ishigaki
Presented by Emmanuel Mignot, Cemagref, France
Although various numerical methods were used to simulate real floods occurring in cities, the validation of the models was never
accurate because of the lack of data about location and event description and about observation for validation. In order to check the
capacities of our 2-dimensional shallow water equations model to simulate an urban flood, we then decided to simulate numerically
an experimental event with well known characteristics and accurate flow measurements. The physical model presented in (Ishigaki
T. et al., 2003) represents the flooding of the city center of Kyoto in Japan due to an overflow from the Kamo river. The 2dimensional numerical simulation of this event was then set up and the experimental and computed data were compared. It appears
that the event was calculated quite fairly in terms of flow depth and flow rates in the streets and in terms of timing. However, some
discrepancies appear between the measurements and the numerical results, mostly due to some topographical local uncertainties
and to the capacities of the equations to model the complex flows in the crossroads.
Optimising storage capacity for stormwater utilisation. V.G. Mitchell*; D.T. McCarthy+; T.D. Fletcher; A. Deletic
Presented by David McCarthy, Monash University, Australia
As the concept of integrated urban water management is integrated into the practice of urban water resource managers, actions,
such as the utilisation of stormwater, which have multiple benefits, are of increasing interest. But due to the space constraints
within both existing urban areas and new urban developments, storage requirements are of paramount interest to potential
implementers. In order to quantify the relationship between storage size and supply reliability for a wide range of urban situations, a
series of scenarios were analysed that have differing climate patterns, urban development densities, reuse demand patterns and
storage types. The seasonality of the demand and the inflow into the store, in addition to the magnitude of these flows were found
to have a significant influence on the sizing of the stormwater stores. The results of the analysis do not indicate that the space
requirements places a significant limitation on the utilisation of stormwater, except in more challenging sites such as constrained
41
high density retrofit applications or in situations where the mean annual demand to storage inflow ratio is approaching or greater
than 100%.
Learning from experiences in applying integrated urban water management concepts in Australia. G. Mitchell*+
Presented by Grace Mitchell, Monash University, Australia
Integrated urban water management (IUWM) solutions take many forms, tailored to the specific characteristics and requirements of
diverse locations that make up Australian cities and towns. This paper summaries a review of a selection of urban developments that
incorporated integrated urban water management principles to gauge its progression with the Australian water industry. The
development and ongoing provision of sustainable urban water services require both sustainable technologies and sustainable actions
and behaviors of many actors to produce the outcomes aspired to. As a result, this paper looks at both the technological aspects of
the case studies and the social setting in which the project occurred. The number and variety of case studies reviewed illustrates
that IUWM is a widely applicable and broadly accepted concept. But its implementation is not without challenges and a number of
barriers to its wide spread practice are identified along with knowledge gaps which require further research effort.
Rainfall-runoff simulation for a tropical catchment. T. A. Mohammed*+; A. H. Ghazali; M. J. M. M. Noor
Presented by Thamer Ahmed Mohammed Mohammed, Universiti Putra Malaysia, Malaysia
Shortage of recorded hydrological data, such as streamflow records, is a very common problem or constraint often encountered in
the planning and design of water resources projects. Reliability of the design, planning and operation for projects of water supply,
irrigation, flood mitigation, hydropower generation, and pollution control, depends mainly upon the length of the records used in the
processes. In this study, a rainfall-runoff model called the basin model, is proposed to predict the mean annual streamflow or runoff
for Bernam River basin, Malaysia. The available record for the streamflow of Bernam River is short and contains some missing data.
The effective rainfall for the selected basin was determined by applying ranking analysis technique. The annual rainfall was
simulated using lag-3 Markov chain stochastic model. Both the basin model and the stochastic rainfall model were calibrated and
validated using the historical record. The validation process of the basin model showed that the absolute error in the model
prediction ranges from 0.11 to 4.02 m3/s. Model testing using Theil’s coefficient showed that the basin model is successful in its
prediction. The value for the Theil’s coefficient was found to be 0.14.
Estimation of urban groundwater recharge from different sources by quantifying soil seepage processes. U. Mohrlok*+; L. Wolf;
J. Klinger
Presented by Ulf Mohrlok, University of Karlsruhe, Germany
The implementation of subsurface processes into the integrated urban water system is essential for an integrated urban water and
mass balance as a base for predicting the evolution of water quality in order to establish sustainable integrated urban water systems.
In particular, the processes of urban groundwater recharge and discharge provide an important transport path for nutrients and
pollutants from the surface and subsurface, e.g. contaminated sites or sewer leaks, to surface waters in urban areas. Urban
groundwater balances require the estimation of urban groundwater recharge which is determined by seepage flow through
unsaturated soils generated by infiltrations to the subsurface from different sources. Because of the very large complexity caused by
the variability of soils, sources and hydraulic boundary conditions several physically based approaches have been developed to
simplify the seepage processes from independent infiltration sources. The considered large spatial variability of the soil properties
and the hydraulic boundary conditions were managed by GIS applications. Recharge rates for individual sources in a case study city
were estimated using several classification methods.
Rehabilitation techniques within the context of CARE-S project. C. Montero*+; A. Villanueva
Presented by Carlos Montero, CLABSA, Spain
Sewer and drainage networks are deteriorating in Europe due to a lack of investment in rehabilitation in these infrastructures.
Several factors cause a soon ageing of the pipelines, decreasing its performance, and many times threatening its structural strength
and its watertightness. The recovery of the original performance level of the deteriorated sewers can be achieved by rehabilitation,
that is: repairing, renovating or replacing the conduits. Computer Aided Rehabilitation for Sewer networks (CARE-S) is a V Framework
Program project, with the participation of 15 research institutions from 10 European countries. The aim of CARE-S is to develop a
suite of tools, which provides the most cost-efficient system of rehabilitation of sewer networks. As part of CARE-S project, a large
amount of rehabilitation techniques have been surveyed and classified. For each technology it has been searched the most
significant parameters and characteristics that define its applicability conditions, their environmental impact and other information
useful to support a multicriteria decision support system and a socio-economic assessment of the impact of the rehabilitation. This
information has been compiled in a database, together with operational methods. A cost tool has been also developed to provide a
rough estimation of the direct cost of rehabilitation works.
Infiltration of stormwater runoff for groundwater recharge, Dane County, Wisconsin. R. Montgomery*+; S. J. Gaffield; N. R.
Zolidis
Presented by Robert Montgomery, Montgomery Associates, United States of America
Groundwater recharge using urban watershed stormwater is being implemented in Madison, Wisconsin in response to State of
Wisconsin permit requirements for a new cogeneration facility that draws its water supply from Lake Mendota. Recharge site
selection and system design required evaluation of available runoff volume, source water quality, soil permeability, potential aquifer
impacts, pretreatment of recharge water, permit requirements, and public perception. Stormwater will be pumped from a flooded
wetland and infiltrated between fairways in an adjacent golf course. Site characterization included hydraulic tests and chemical
analyses of the pond and groundwater. We used an integrated modeling approach to predict system performance and impacts,
including hydrologic modeling of watershed runoff, hydraulic modeling of pond stage fluctuations and water supply, and groundwater
modeling of water table mounding and aquifer transport relative to nearby water supply wells. The two main issues identified as
critical to the recharge project success were: 1) minimizing soil clogging due to suspended solids loading through microfiltration and
designing to allow inactive periods; and 2) understanding potential risks to groundwater quality and benefits to baseflow and water
quality of lakes in the watershed.
Decision support system for storm design level based on inundation damage simulation and risk analysis using GIS. M. Morita*+;
K. Yamashita
Presented by Masaru Morita, Shibaura Institute of Technology, Japan
To decide a storm design level for flood prevention in urban areas is a crucial task for local governmental engineers. The objective of
this study is to present a risk analysis method for storm design level decisions. The concept of “risk” is defined as the product of
flood damage and its occurrence probability. The study also presents a flood damage prediction system using GIS to calculate flood
damages for any design storms with different return periods. The calculated monetary damages for the design storms with their
occurrence probabilities enable us to quantify flood inundation risk based on the concept of “risk.” The Tokyo Metropolitan
Government has adopted a storm design level of 15-year return period, 75 mm/hr. The government constructed in 1997 a flood
control reservoir, Loop-7 Reservoir, for flood risk reduction in the Kanda river basin. Through the risk analysis method, the relation
between storm design level and annual risk density is calculated for two cases: with and without the flood control reservoir. The
design level of the government, 75 mm/hr, is discussed on the basis of the annual risk density curves and the risk reduction effect of
the reservoir is clarified by the results of the risk analysis.
Groundwater surcharging of sewers: example from Doncaster, England of a technique for identifying its extent. B.L. Morris*+; I.
Neumann; J.E. Cunningham; R.L. Hargreaves; J. Rueedi; A.A. Cronin
Presented by Brian Morris, British Geological Survey, United Kingdom (Great Britain)
A technique is described for the rapid assessment of which parts of an existing sewer or pluvial drain network may be below the
watertable and, therefore, in areas of potential gain from groundwater. The technique, which arose from data conditioning for the
pipeline leakage part of an urban water balance model array, can be used together with a groundwater flow model to undertake
scenario modelling. The extent of effects on the sewer network from different groundwater level rebound scenarios can then be
rapidly predicted. Such changes in water level can arise for example from decline in nearby urban/periurban groundwater
abstraction or as a consequence of increased urban recharge. An example is given for a 6.3 km2 suburb of Doncaster, England with a
128 km sewer and pluvial drain network.
Comparison between two methodologies for urban drainage decision aid. P.M. Moura*+; M.B. Baptista, S. Barraud
Presented by Priscilla Moura, UFMG, Brazil
The objective of the present work is to compare two methodologies based on multicriteria analysis for the evaluation of stormwater
systems. The first methodology was developed in Brazil and is based on performance-cost analysis, the second one is ELECTRE III.
Both methodologies were applied to a case study. Sensitivity and robustness analyses were then carried out. These analyses
demonstrate that both methodologies bring equivalent results, and present low sensitivity and high robustness. These results prove
that the Brazilian methodology is consistent and can be used safely in order to select a good solution or a small set of good solutions
that could be compared with more detailed methods afterwards.
Design of a retention pond: comparison of stormwater quality models with various levels of complexity. M. Mourad*; J. L.
Bertrand-Krajewski+; G. Chebbo
Stormwater quality simulation models are useful tools for the design and management of sewer systems. Modelling results can be
sensitive to experimental data used for calibration. This sensitivity is examined for three modelling approaches of various
complexities (site mean concentration approach, event mean concentration approach and build-up, washoff and transport modelling
approach) applied to a dry detention pond design case study, accounting for the variability of calibration data and their effect on
simulation results. Calibrated models with different calibration data sets were used to simulate three years of rainfall with different
detention pond volumes. Annual pollutant load interception efficiencies were determined. Simulations results revealed i) that there
is no advantage in using the EMC model compared to the SMC model and ii) that the BWT model resulted in higher design ratios than
those given by the SMC/hydraulic approach. For both EMC and BWT models, using an increasing number n of events for calibration
leads to narrower confidence intervals for the design ratios. It is crucial for design ratios to account for successive storm events in
chronological order and to account for the maximum allowable flow to be transferred to the downstream WWTP.
Innovative construction of an on-line storage tank. M. Mrowiec*+
Presented by Maciej Mrowiec, Czestochowa University of Technology, Poland
The paper presents a new technical solution in the field of stormwater detention in the drainage systems. The proposed innovative
construction of an on-line detention pipe is hydraulically more effective than a traditional single chamber construction and allows to
significantly reduce the required storage capacity, depending on the flow reduction factor. Each of characteristic phases was
described as the set of differential equations which allows to conduct a standard routing method – the relationship between inflow
and outflow over time - and to determine the required volume of the tank. Based mathematical models of the reservoir verified at a
laboratory scale, the possible reduction of storage capacity may range from 3.5 % for flow reduction factor equal to 0.1, to even 64 %
for the value of factor equal to 0.9. The use of the proposed construction allows to significantly reduce the length or the diameter of
the tank. For existing storage tanks it can increase its storage capacity with low investment costs. Additionally, the proposed design
assure a better hydraulic conditions during low flows – in combined sewer systems considerably higher velocities can be reach during
dry weather. Maintenance costs also may be reduced due to lower cleanse needs in comparison with single chamber tank.
influence of rainfall runoff and sewer characteristics on soluble transport. I. Müller*+; P. Krebs
Presented by Ina Müller, Dresden University of Technology, Germany
When looking at acute receiving water impacts due to combined sewer overflows the characteristics of rainfall runoff and the sewer
properties may influence the peak loads of dissolved matter significantly. In this paper, the influences on the dynamic soluble
transport in the sewer are evaluated by means of hydrodynamic simulations. The simulations are based on different scenarios for
rainfall runoff characteristics and sewer properties.
Comparison of infiltration flows at three types of infiltration facilities in serial rainfall events with different characteristics. M.
Murakami*+; H. Furumai; F.Nakajima; H.K.P.K. Jinadasa; R.K. Aryal
Presented by Michio Murakami, The University of Tokyo, Japan
Infiltration facilities function for the groundwater recharge, retention of non-point pollutants as well as the reduction of stormwater
peak flow in urban areas. Although there have been several simulation researches focusing on reduction of stormwater peak flow by
introduced infiltration facilities, limited simulations have been done to estimate the water balance and discuss the characteristics of
infiltration flows. In this study, runoff quantity simulation was carried out to compare the contribution of infiltration volume for
rainfall events with different characteristics and the quality simulation was also applied to discuss how infiltration facilities work for
the retention and/or overflow of pollutants. The quantity simulation showed that the excess runoff to sewer pipes is significantly
reduced by infiltration facilities, especially infiltration LU curbs, irrespective of rainfall characteristics. The runoff quality simulation
showed the importance of the mechanism of the wash-off and resuspension of sediment within infiltration facilities. Surface
pollutants may be retained within infiltration facilities in weak rainfall events while the retained sediments contribute to pollutant
overflow in heavy rainfall events.
Integrated modeling and multi-objective evolution strategy as a method for water quality oriented optimization of urban
drainage systems. D. Muschalla*+; M. Ostrowski; K. Schröter; S. Wörsching
Presented by Dirk Muschalla, TU Darmstadt, Germany
This paper deals with the development of a new multi-objective evolution strategy in combination with an integrated pollution-load
and water-quality model. The optimization algorithm combines the advantages of the Non-Dominated Sorting Genetic Algorithm and
Self-Adaptive Evolution Strategies. The identification of a good spread of solutions on the pareto-optimum front and the optimization
of a large number of decision variables equally demands numerous simulation runs. In addition, statements with regard to the
frequency of critical concentrations and peak discharges require continuous long-term simulations. Therefore, a fast operating
integrated simulation model is needed providing the required precision of the results. For this purpose, a hydrological deterministic
pollution-load model has been coupled with a river water-quality module. Waste water treatment plants are simulated in a
simplified way. The functionality of the optimization and simulation tool have been validated by analyzing a real catchment area
including sewer system, WWTP, water body and natural river basin. For the optimization/rehabilitation of the urban drainage system
both innovative and approved measures have been examined and used as decision variables. As objective functions investment costs
43
and Environmental Quality Standards have been used. The determined approximation to the pareto-optimum front is presented and
discussed.
Building a bioretention area in a cold climate. T. M. Muthanna*+; S. T. Thorolfsson
Presented by Tone Merete Muthanna, NTNU, Norway
This paper describes an experimental field work setup for testing the performance of bioretention areas in a cold climate setting at
Risvollan urban hydrological station in Trondheim, Norway. Bioretention focuses on water retention, peak flow reduction, and water
quality improvement with respect to heavy metals and sediments. However, in colder climates the performance of bioretention
areas are to a large extent unknown. The most problematic with winter conditions are the many interchanged snow and rainfall
events, creating rain-on-snow events, resulting in ice formation, then melting and often refreezing. This causes blockage of
stormwater inlets and elevated risk of flooding. The focus of this paper will be on the hydraulic retention properties of the system.
The performance of the bioretention area will be evaluated based on peak runoff reduction and detention capabilities. The results so
far indicate promising results with respect to detention capabilities also during typical coastal winter conditions. The outflow from
the bioretention area was compared to runoff from an equal size impervious area. The average reduction in peak flow rates
compared with impervious surface runoff was 49 %. The actual reduction will vary dependent on pre event
Two-phase stratified flows in downwardly inclined pipes. Linear stability analysis. M. Mutti*+; G. Becciu; A. Paoletti
Presented by Matteo Mutti, Milan Polytechnic Institute, Italy
In free surface flow modelling, interactions between air and water are often neglected. However, considering the shear stresses at
the air-water interface leads, on the one hand, to water depths which may be different from those predicted from standard singlephase models and, on the other, to a better identification of unstable flow conditions. In both cases, the differences can be relevant
in testing sewer networks, especially when high water depths and flow rates are involved or when the aeration system is improperly
designed. The focus of this work is to show the influence of these interactions in predicting flow pattern transitions. A rather general
mathematical model for the simulation of stratified multi-phase flows is then presented. One-dimensional multi-fluid equations are
derived in transient form for incompressible and isothermal flow. Theoretical transitions from stratified flow are calculated through
linear stability theory and both inviscid and viscous Kelvin-Helmholtz stability analyses are used. By assuming a particular form of the
disturbances occurring on the interfaces, an eigenvalue problem is produced, the spectrum of which rules the growth of infinitesimal
perturbations. Steady state solutions and neutral stability curves for air-water flows in downwardly inclined pipes are considered and
flow pattern transitions are investigated analysing the effects of pipe inclination, diameter and friction factors.
Transfer of hydrophobic contaminants in urban runoff particles to benthic organisms estimated by an in vitro bioaccessibility
test. F. Nakajima*+; K. Saito; Y. Isozaki; H. Furumai; A.M Christensen; A. Baun; A. Ledin; P.S. Mikkelsen
Presented by Fumiyuki Nakajima, the University of Tokyo, Japan
An in vitro bioaccessibility test was applied for assessing the transfer of polycyclic aromatic hydrocarbons (PAHs) present in road
dust, into benthic organisms living in receiving water body. The road dust is supposed to be urban runoff particles under wet weather
conditions. Sodium dodecyl sulfate (SDS) solution was used as a hypothetical gut fluid. Pyrene, fluoranthene and phenanthrene were
the main PAH species in the SDS extractable fraction of road dust as well as the whole extract. Benzo(ghi)perylene showed relatively
low concentration in the SDS extract in spite of high concentration in the original dust. The PAH composition in benthic organisms
(polychaetes) did not correspond with that of the surrounding sediment and the PAHs detected were also detected in high
concentration in the SDS extract of road dust. When testing the toxicity of the extracted contaminants by a standardized algal
toxicity test, SDS extracts of a detention pond sediment showed higher toxicity than the pore water of the corresponding sediment.
Sediment suspension showed a comparative toxicity with 0.1% SDS extract. From the result, the in vitro bioaccessibility test seems
more suitable to evaluate the exposed contaminants than the traditional organic solvent extraction method and the SDS extracted
fraction is applicable to toxicity tests reflecting the digestive process.
Research of oil ball countermeasures through high-speed filtration. Y. Nakayama*+; N. Nakamura
Presented by Yoshihiko Nakayama, NGK INSULATORS,LTD, Japan
Combined sewer systems entail a problem of direct discharge of some wastewater into public water areas. In Yokohama, too,
combined systems serve about 25 percent (10,000 hectares) of the city area, and reduction of the pollutant load discharged into
Tokyo Bay in wet weather is an important priority. The central districts have many restaurants, and wastewater from them contains
a lot of oil and fat, and forms oil balls inside sewers. In heavy rainfalls, the strong flow in pipes flushes these balls into wastewater
treatment plants, and inflow over the treatment capacity is directly discharged into the Bay. Although the city has installed
stormwater tanks to trap the first-flush stormwater, stormwater in excess of their capacity is, in effect, discharged without
treatment. This situation required the development and utilization of technology for treatment of large quantities of highly polluted
wastewater containing oil balls and other debris. In response, the city government and NGK Insulators, Ltd. collaborated in the
creation of a new upflow filtration system applying extremely fine filter media. In a long-term proving test, the system operated
free of clogging or other trouble and simultaneously removed debris, SS, and BOD in an efficient manner.
An assessment of the cost effectiveness of vegetation harvesting as a means of removing nutrient and metals from ponds. F.
Napier*+; M. Barrett; C. Jefferies
Presented by Fiona Napier, University of Abertay Dundee, United Kingdom (Great Britain)
This paper reports on an investigation to quantify the mass of pollutants removed from a stormwater retention pond by routine
vegetation harvesting. The amount of plants can increase the costs of ponds, and the increased costs of plant maintenance may not
be justified by enhanced pollutant removal. This study provides some of the basic information, previously lacking, which is needed to
come to such decisions. The study facility was La Costa pond, a retention pond in California used to treat highway runoff. Water
quality monitoring data indicate that the pond removed 43 percent of the total nitrogen entering the facility, with 5 to 7 percent
directly attributable to harvesting the vegetation – in this case cattails (Typha). The data also indicate that 48 percent of the total
annual phosphorus was removed from the runoff, with the harvested vegetation responsible for between 3 and 8 percent. Metal
uptake by the vegetation was substantially less than nutrients. Total removal of copper, lead and zinc by the pond varied between
57 and 93 percent, with the harvested vegetation accounting for less than 2 percent of removal. Issues addressed in the paper
include the cost implications of harvesting and ways of improving vegetative pollutant removal.
Flood-damage curves: Methodological development for the Brazilian context. N. Nascimento*+; M. Baptista; A. Silva; M. L.
Machado
Presented by Nilo Nascimento, Federal University of Minas Gerais, Brazil
The present paper describes the main results of an on-going research aiming to develop standard flood damage data in the form of
generic flood-damage curves. This type of curve allows estimating flood damages from the depth of inundation. Although the
research project encompasses flood damages on different urban land use activities (residential, commercial, services and industrial
land uses), the paper focus on residential flood damage information. The empirical data used on this research was obtained from
systematic surveys performed in the city of Itajubá, a town with 85.000 inhabitants located in the Sapucaí river valley in the Southeastern region of Brazil, during the year of 2002. The survey consisted in interviewing residents in the Itajubá flood prone urban area
in order to develop a data base characterizing the social class, the building fabric, the contents (inventory items) and the damages
caused to dwellings by a reference flood event, the 2000 flood event. During this event, the town had more than 70% of its urban
area flooded for three days and, in some densely urbanised areas, the depth of water was superior to three meters.
Recent findings on sinks for sulfide in gravity sewer networks. A. H. Nielsen*+; T. Hvitved-Jacobsen; J. Vollertsen
Presented by Asbjørn Haaning Nielsen, Aalborg University, Denmark
Sulfide buildup in sewer networks is associated with several problems, including health impacts, corrosion of sewer structures and
odor nuisance. In recent years, significant advances in the knowledge of the major processes governing sulfide buildup in sewer
networks have been made. This paper summarizes this newly obtained knowledge and emphasizes important implications of the
findings. Model simulations of the in-sewer processes important for the sulfur cycle showed that sulfide oxidation in the wetted
biofilm is typically the most important sink for dissolved sulfide in gravity sewers. However, sulfide emission and thereby potential
hydrogen sulfide buildup in the sewer atmosphere is of particular importance in sewers constructed with small diameter pipes, in
sewers constructed with steep slopes and in sewers conveying low pH wastewater. Precipitation of metal sulfides is only important
when the sulfide concentration in the wastewater is low; i.e., less than 1 mg S/L.
Using measured data for reducing precipitation distribution uncertainty. M. K. Nielsen*+; M. Lindstrøm; K. V. Gernaey; H. Madsen
Presented by Marinus K. Nielsen, Waste Water Control, Denmark
The analysis of on-line sewer system data, for example obtained from pumping stations, confirms that rainfall is far from being
uniformly distributed. As a consequence, CSO estimates from deterministic sewer models using a few rain gauges as a source for
input rain series data, and thus assuming a uniform distribution of the rain over a catchment, was found to be very unreliable. It is
thus questionable if evaluations based on sewer models are useful when extending existing catchments with storm water basins or
other CSO reducing designs. Certainly for sewer control, an on-line flow rate estimate is a necessity for real-time control to be
useful. In fact, the rain distribution over a catchment is so uneven that it is more the knowledge on the total flow distribution
originating from different subcatchments during each rain event that provides the major explanation for real-time control benefits in
an integrated system. Better on-line data, both in quality and quantity, and technological developments facilitating data transfer
and handling capabilities will eventually force the sewer system specialist to accept the use of on-line sewer data as a valuable
information source, and will thus allow reducing the systematic errors in today’s standard engineering tools.
From pumping station monitoring to integrated system control - 30 years of practical experience with R.T.C. Of wastewater
systems, with implications. B. Nielsen+; M. K. Nielsen*
Presented by Bjarne Nielsen, Aalborg municipality, Denmark
Best Management Practices (BMP's) are developed on the basis of the best available techniques and their cost set against their
quality, maintenance and installation costs. Therefore, plans and practices are in constant development, keeping the balance
between safe and simple documented techniques and new, potentially more cost efficient, techniques. BMP is about keeping close
to, but at a safe distance from the bleeding edge of new technologies. Aalborg Municipality has experienced this over a long period,
and tested Real Time control (RTC) techniques. The paper presents some of the experiences Aalborg municipality has had with RTC.
The lesson has been: Keep It Simple and take small steps into unknown land. However, if advanced techniques are needed we Keep It
Structured, so that the cause of a problem can be identified and in this connection the RTC can result in significant improvements.
An assessment of the effect of modelling and control indicates that the combined result of control and the extension with storm
tanks or sedimentation tanks at the Aalborg treatment plant has yielded a saving of about 10 million Euro.
Evaluation of pollutant runoff loads from non-point sources under the wet weather condition. M. Noguchi*+; N. Morio; M.
Nishikawa; M. Furue
Presented by Masato Noguchi, Nagasaki University, Japan
There are lots of closed water bodies. At Nagasaki in Japan, for making vivid an activity of urban life, Mizube-no-Mori Koen, that is a
park of river-front forestry, has been constructed, by installing an artificial open channel and its promenade. This channel has been
dammed at the downstream and so it is a closed water body. In order to make clear the water, pollutants discharged into it should
be reduced, especially from non-point sources. Attaining its purpose, a field observation of pollutant runoff loads has been done
under wet weather conditions. Here, rate of pollutant runoff has been evaluated through a field observation at the Dejima River
basin. In this paper, detachment rate of Total Nitrogen (T-N) under wet weather conditions has been revealed related to a condition
of watershed influenced by a series of rainfall so far. Even though there is a simplified model using a relationship between pollutant
runoff loads and discharge, i.e. L-Q curve, proposed method offers an effective tool for estimating the pollutant runoff loads under
wet weather conditions from non-point sources.
Uncertainty analysis in sewer systems performance evaluation. V. Notaro*+; G. Freni; E. Oliveri; G. La Loggia
Presented by Vincenza Notaro, Università degli Studi di Palermo, Italy
In recent years, in order to analyse complex urban drainage systems and to identify the most effective measures for improving their
efficiency, many parameters, or indicators, have been defined and many methodologies have been proposed in order to quantify
sewer systems performance in the most objective and general way. However, some uncertainty arises in these methodologies due to
choices which the user has to take in applying the procedure. Thus, performance analysis results are affected by operator experience
and they are mainly useful for comparison between different scenarios applied to the same system. In the present paper, a
statistical analysis of sewer systems performance has been carried out, aimed to quantify the uncertainty depending on user
subjective selections needed during the procedure and affecting the assignment of PI level of service. Considering historical
statistically independent rainfalls as input, the proposed methodology applies Monte Carlo simulations to generate sewer system
global performance for different penalty curve shapes. The statistical analysis of the obtained frequency–performance relationships
allows for improving the robustness of the method and for increasing the user confidence in the methodology results. The proposed
analysis has been applied to a real case study in Palermo (Italy).
Gain scheduled predectived control for integrated wastewater systems in storm conditions. M. O'Brien*+; F. Camilleri; R.
Vilanova; A. Ordys
Presented by Marie O’Brien, University of Strathclyde, United Kingdom (Great Britain)
The aim of this paper is to demonstrate the application of integrated control in minimizing the effect of wastewater treatment
plants (WWTP) and overflows on a river basin under wet weather conditions. An Integrated Urban Water System comprised of the
WWTP, river and sewer is considered. The control strategy is based on model predictive control, which enables the physical and
quality constraints to be explicitly incorporated into the control solution. Model based predictive control of dissolved oxygen that
considers the entire integrated process is presented. The linear control method used is extended to this nonlinear system using fuzzy
gain-scheduling. Simulation results are presented to demonstrate the effectiveness of the proposed integrated control system.
Analysis of Storm Water Runoff Impacts on Wastewater Treatment Facilities in Gaborone. P. Odirile*+
Presented by Phillimon Odirile, University of Botswana, Botswana
45
Runoff management has been every city’s concern for many years all over the world and storm water management is often referred
to as the redheaded stepchild of municipal government. However, it continues to be a major problem for most city engineers and
planners as they are faced with a challenge of improving performance in the operations of the drainage and wastewater collection
systems in Botswana. This paper analysis the effects of the storm water infiltration into sewers on the economics of sewer designs
and as well as on the quality of wastewater reaching the Gaborone Wastewater Treatment Plant (GWTP). The main objective of the
work was to investigate whether or not the wet weather conditions could affect the design flows and wastewater quality at the
Wastewater Treatment Plant. This was achieved by comparing flow rates and wastewater quality during Dry and Wet Weather
conditions.
New Act Legislated in Japan for Well-balanced Hydrological System and Urban Inundation Prevention. A. Okashita*+; K. Ogata
Presented by Atsushi Okashita, Ministry of Land, Infrastructure and Transport, Japan
This paper presents the new act legislated in Japan for well-balanced hydrological system and urban inundation prevention. The
comprehensive mitigation measures for flood control have been carried out by the government for nearly 30 years. Since it does not
have a legal basis to stand on, there is a limitation to implement the measures on a mandatory basis. In order to supplement this
disadvantage, the new act was constituted to bridge the existing laws such as the river law, the sewerage law, the flood prevention
law and the town planning law so that the concerted effort of river administrators, sewerage administrators and local governments
becomes effective. The comprehensive mitigation measures are able to be effectively promoted based on the river basin inundation
prevention plan over the river or the river basin legally designated by the Minister of Land, Infrastructure and Transport, Prefectural
Governor or Mayor. Especially, by applying this new act it has become much easier to impose severe restriction on the acts that
hamper the function of storm water retention and infiltration. In addition to the flood control, this act will contribute to achieve the
well-balanced hydrological system in urban areas as well.
Consciousness survey towards promotion of wide use of rainwater infiltration facilities. H. Okui*+; M. Imbe
Presented by Hiroyuki Okui, Association for Rainwater storage and Infitration, Japan
In order to promote the wide use of the infiltration facilities introduced into individual houses, the consciousness survey was done by
means of the questionnaire intended for the visitors at the housing exhibition, the member of civic organizations on the activity for
river improvement, citizens who installed the facilities in their own houses and the sewer work contractors who deal with the
drainage piping work. This paper is a report on the analysis of the questionnaire. The target of this consciousness survey was to grasp
the reason why the ordinary people do not introduce infiltration facilities into their houses. The contents of questionnaires were
carefully considered to find out the disincentives for the promotion. About 3000 people were sampled as the object of questionnaire
and the effective number of respondent was about 1000. Responsed answers were analyzed and it was realized that the
understanding of citizens about infiltration facility is not enough. At the same time, it was understood that the incentive for the
people who install the facilities will be effective for the promotion. It was also understood that the cooperation with the sewer work
contractor is necessary.
Sampling for representative micropollutant loads in sewer systems. C. Ort*+; W. Gujer
Presented by Christoph Ort, EAWAG, Switzerland
Most commercially available auto-sampling devices do not support a continuous flow-proportional sampling mode, which would
conceptually be the best for collecting representative composite samples. Instead different discrete sampling modes are available.
Household chemicals can show considerable random short-term variations. With the anticorrosive benzotriazole, relating to a middlefrequent household activity, we show that, besides an accurate flow meter, mainly three factors are decisive for the
representativeness of a substance’s average load: the substance’s load pattern, the sampling frequency and the length of the
composite sample. When the sampling intervals are 10 minutes or longer, errors in the order of +/-40 % (standard deviation) or more
have to be accepted, if the substance of interest is contained in a low number of wastewater pulses (i.e. the level of household
activity). This particularly holds true for specific pharmaceuticals like e.g. carbamazepine. Ammonium would be less critical,
because it relates to a large number of sources.
Influence of advection, dispersion, transient storage and biochemical decay on the propagation of pollutants discharged by wet
weather overflows or continuous spills into streams. A. Paoletti; U. Sanfilippo*+; I. Innocenti
Presented by Umberto Sanfilippo, Politecnico di Milano, Italy
The paper analyses, under the hypothesis of steady flow in the receiving stream, the relative importance of the physical processes of
advection, dispersion, transient storage in dead zones and biochemical decay on the one-dimensional propagation of pollutants, for
intermittent spill (like from a sewer overflow in wet weather) or continuous spill (like from a waste water treatment plant outflow),
depending on river morphology and biochemical decay rate. Two different reaches, one straight and the other meandering, are
exploited as experimental sites, where a number of time of travel surveys allows to calibrate the ADE, OTIS and ADEK models,
comparing their performances. Afterwards, the two different reaches are virtually extended up to 20 kilometres, to simulate
numerically the propagation of pollutographs. In case of intermittent spill, such a propagation shows that persistence time above a
given concentration threshold at progressive distances downstream increases for low concentrations and decreases for high
concentrations, as the concentration curve is spreading due to the longitudinal dispersion, especially for the meandering reach. On
the contrary, in case of continuous spill, the longitudinal dispersion has a negligible effect on concentration, while dead zones
reduces the mean velocity, consequently increasing the translation time and indirectly facilitating the biochemical decay of
pollution.
Propagation of pollutants discharged by urban drainage overflows in natural streams in unsteady flow conditions. A. Paoletti; U.
Sanfilippo*+; D. Sessa; I. Innocenti
Presented by Umberto Sanfilippo, Politecnico di Milano, Italy
The first aim of the paper is to present a new conceptual approach to simulate the propagation of dissolved pollutants in onedimensional streams under unsteady flow conditions by means of the superimposition of effects. Such approach consists in the
extension to the unsteady flow of an already existing so-called IUP approach, already set up and widely tested for steady flow. The
reliability of such an extension to unsteady flow is validated comparing it with the well known OTIS model of USGS, which is based on
a set of differential equations that must be solved through finite partial differences. Afterwards, this conceptual model is applied to
investigate, through some significant numerical examples in unsteady flow conditions, the propagation along receiving streams of
pollutants discharged by intermittent spills coming from the sewer overflows of urban drainage systems. The main result is that in
many cases the persistence time above a given concentration threshold in the receiving stream increases progressively along the first
sections downstream the spill, but then tends to decrease after an intermediate peak, which locates the critical section from this
point of view; and the higher is the longitudinal dispersion value, the less downstream such a critical section is located.
Analysis of urban runoff control with infiltration facilities. F. Papa+; B. J. Adams*
Presented by Fabian Papa, Valdor Engineering Inc., Canada
This paper presents two methodologies for estimating the impact of infiltration facilities on reducing stormwater runoff volumes,
and pollutant loads, from urban drainage systems. The methodologies have previously been developed using derived probability
distribution theory, often referred to in the literature as analytical probabilistic modelling, and differ in that they employ different
hydrologic models for the transformation of rainfall to runoff. Moreover, the original model derivations employed herein were
developed for the analysis of stormwater detention facilities (dry ponds), and are adapted herein for the analysis of infiltration
facilities. The summary of model expressions presented in this paper permits the reader to perform the necessary calculations to
design and analyze the performance of stormwater infiltration facilities with the use of a calculator or computer-based spreadsheet
application. Results are generated using the models, and various sensitivity analyses presented, illustrating the power of the models.
The models are then used as a basis for comparison with guidelines on the design of such facilities in the province of Ontario,
Canada. The results of this comparison suggest that the current guidelines may yield infiltration facilities insufficient in size to meet
the performance levels intended to be satisfied by such facilities.
Pollution in storm water runoff in a highway toll gate area and performance of a source-area treatment technology. S. Papiri; C.
Ciaponi; S. Todeschini*+; P. Valcher
Presented by Sara Todeschini, Hydraulic and Environmental Engineering, UNIVERSITY, Italy
This report describes the experimental equipment and the first results of a study to characterise the quality of storm water runoff in
the area of a medium traffic flow highway toll gate and also to evaluate the efficiency, for this type of surface, of a “source-area
treatment” technology currently on the market called EcoDrainTM. This system was designed to reduce pollutants carried into storm
drains by water runoff via filtration and absorption. The report presents the results of tests carried out in the Hydraulic laboratory of
the University of Pavia to ascertain the hydraulic performance of the device. Furthermore, this report describes the experimental
equipment installed near a Cremona (Northern Italy) toll gate to field-test the system’s ability to decrease pollutants and the first
results regarding the quality of storm water runoff in this area.
Estimates of urban stormwater runoff using GIS. M. H. Park*+; I. H. (Mel) Suffet; M. K. Stenstrom
Presented by Mi-Hyun Park, UCLA, United States of America
Urbanizing watersheds are facing many challenges and significant efforts are being made to protect receiving water quality and the
natural habitats in the watersheds. In the Sweetwater River watershed, current efforts focus primarily on urban runoff since
stormwater from urban land uses has been identified as a major source of contamination to the Sweetwater reservoir. Urban land
use information is being used to estimate and manage stormwater runoff pollution. Although there have been several monitoring and
modeling efforts to predict stormwater quality, few attempts have been made to spatially estimate pollutant loadings. In this
research, we estimated stormwater pollutant loadings from land use data and generated spatial estimates of pollutant loading in the
watershed. Our goal was to identify the areas that discharge high pollutant loading and to visualize this information by generating
pollutant loading maps. The result shows that commercial, public, industrial, and transportation land uses are important to manage
stormwater pollution despite their small area and are early targets for best management practices (BMPs). The results can be used to
develop BMPs and to assist in developing urban runoff diversion systems to protect the Sweetwater reservoir.
Urban run-off volumes dependency on rainfall measurement method - Scaling properties of precipitation within a 2x2 km radar
pixel. L. Pedersen*+; N. E. Jensen; M. R. Rasmussen; M. G. Nicolajsen
Presented by Lisbeth Pedersen, Niras Consulting Engineers and Planners A/s, Denmark
Urban run-off is characterized with fast response since the large surface run-off in the catchments responds immediately to
variations in the rainfall. Modeling such type of catchments is most often done with the input from very few rain gauges, but the
large variation in rainfall over small areas suggests that rainfall needs to be measured with a much higher spatial resolution (Jensen
and Pedersen, 2004). This paper evaluates the impact of using high-resolution rainfall information from weather radar compared to
the conventional single gauge approach. The radar rainfall in three different resolutions and single gauge rainfall was fed to a MOUSE
run-off model. The flow and total volume over the event is evaluated.
Artificial intelligence techniques for short-term rainfall forecast. I.J. Pelczer*; H.L. Cisneros Iturbe+
Presented by H. Leonardo Cisneros-Iturbe, Instituto de Ingeniería. UNAM, Mexico
The purpose of the present study is to evaluate the appropriateness of the use of artificial intelligence techniques for short term
rainfall forecast in a large urban basin. The work represents the first step of a year-term enterprise that has as final purposes the
spatial-temporal characterization and forecast of rainfall events in Mexico City based on rain-gauge data only and modeling the
rainfall-runoff relation for the same region. In a first approach we analyzed the viability of different artificial intelligence techniques
(neural networks, k-neighbor method and regression trees) for 15 minute, site specific, quantitative rainfall forecast in a real-time
system. In order to improve forecast for exceptional values of rain we performed a classification of the rain events into three groups.
For each cluster a series of experiments were conducted in order to find adequate parameters for the used methods. Performance
was assessed with the Nash-Sutcliffe and correlation coefficient. For all groups, the k-nearest neighbor approach leads to best
results. We extracted rules for data grouping and forecast values in order to make explicit relations between variables and assure
real-time operability of the system. The obtained results encourage the use of the mentioned techniques as complementary tools in
hydrological applications.
Underground sedimentation systems for treatment of highway runoff in dense city areas. T.J.R. Pettersson*+; A.-M. Strömvall; S.
Ahlman
Presented by Thomas Pettersson, Chalmers University of Technology, Sweden
The pollutant characterization, removal efficiency and function of a newly constructed underground sedimentation system for
treatment of highway runoff have been investigated. Results from flow weighted sampling, during eight consecutive storm events,
show a high inflow of heavy metals and carcinogenic PAHs. The concentrations of carcinogenic PAHs in the inlet water exceeded the
Swedish guideline values for polluted groundwater at petrol stations. The relatively high amounts of specific PAHs such as pyrene,
fluoranthene, chrysene, and benzo(g,h,i)perylene, indicate road asphalt, vehicle exhaust and tyre rubber as important sources of
pollution. In the outlet water, the concentrations of all PAHs were effectively reduced and far below the guideline limits. The heavy
metals found in highest concentration in the inlet water were zinc, copper, chromium, lead, cadmium and nickel. They all, except
nickel, exceeded the Swedish quality criteria values for watercourses, even in the outlet water to the urban river. The average
pollutant removal efficiencies of the treatment system were for TSS ~ 30 %, VSS ~ 25 %, heavy metals 15–35 % and for PAHs ~ 30 %.
The results also show that the efficiency of the sedimentation construction could be improved by optimisation of operational
conditions such as detention times.
47
General characteristics of pit inlet capacity relationships. D. Pezzaniti*; G.G. O'Loughlin+; J.R. Argue
Presented by Geoffrey O'Loughlin, Anstad Pty Ltd, Australia
The importance of stormwater inlet pits, the types of inlets, and the need for inlet capacity relationships at high flowrates are
covered in the first part of this paper. A case study is used to show differences in published inlet relations and the problem of
extrapolating relationships that were originally developed for relatively low flows. The US Federal Highway Administration Hydraulic
Engineering Circular No. 22 (HEC22) methodology was used as a benchmark for comparisons with Australian laboratory inlet capacity
test data and relationships in manuals, with the aim of extrapolating published relationships. It was not possible to establish precise
relationships, but qualitative information developed for various kinds of inlets can be used, together with a spreadsheet
implementing HEC22 procedures, to develop capacity relations for many kinds of inlets. Brief comments are provided on effects of
inlet blockage and on cumulative effects in large pipe networks.
1D and 2D modelling of urban drainage systems using XP-SWMM and TUFLOW. B. C. Phillips*+; S. Yu; G. R. Thompson; N. de Silva
Presented by Brett Phillips, Cardno Willing (NSW) Pty Ltd, Australia
The release of a revised NSW Floodplain Management Manual in 2001 established a new direction for urban flood management in NSW
by redefining the floodplain as the area bounded by the PMF and the removal of the distinction between “mainstream flooding” and
“local flooding”. This new direction and the increasing availability of aerial laser scanning have ramifications for urban flood studies.
The trend in NSW and elsewhere has been for the growing adoption of 2D models as the new benchmark for urban flood studies. To
enhance its capability to model urban drainage systems the TUFLOW 2D hydrodynamic model is being incorporated as a layer into an
XP-SWMM2D package. Two case studies that demonstrate the new 1D/2D modeling capability of TUFLOW and XP-SWMM2D are
described. The first case study is of a reach of Prospect Creek in the City of Fairfield. A 2D and a combined 1D/2D models of the
floodplain were assembled and run. A comparison of 1D, 1D/2D and 2D results is given. The second case study is of a local drainage
subcatchment that demonstrates the interaction between the piped drainage system and 2D surface overland flows. It is concluded
that the 2D hydrodynamic modeling layer in the XP-SWMM package offers users new opportunities to undertake more detailed
investigations of urban drainage systems and of urban waterways and floodplains. It also demonstrates the on-going evolution of the
XP-SWMM package in response to the changing needs of stormwater managers.
Improving the sustainability of on-site detention in urban catchments. B.C. Phillips*+; A.G. Goyen; S.J. Lees
Presented by Brett Phillips, Cardno Willing (NSW) Pty Ltd, Australia
The upper catchment of the Parramatta River is one of the most urbanized catchments in Sydney and Australia. The Upper
Parramatta River Catchment Trust (UPRCT) was established in 1989 to address the impacts of urbanization on flooding in the 110 km2
catchment. An On-Site Detention (OSD) policy was adopted by the UPRCT in November 1991 and has been applied to all new
developments in the catchment since that time. The Trust has also published a detailed OSD Handbook. The fourth edition is due to
be released in early 2005. Further investigations have been undertaken of an OSD system that controls site runoff in both the 1.5
year and 100 year ARI storms. These assessments also provided guidance on the appropriate modification of OSD parameters when:
less than 100% of lot runoff is captured in an OSD tank ie. partial bypassing of the OSD tank; a rainwater tank is installed on a lot
with dedicated airspace or without dedicated airspace. These further investigations are described and the guidance provided in the
fourth edition of the UPRCT Handbook is discussed. It is concluded that the fourth edition of the UPRCT OSD Handbook will improve
the sustainability of urban drainage practices in the upper Parramatta River catchment by not only preventing increased flooding in
major (100 year ARI) storms but will also better control flooding in frequent (1-2 year ARI) storms thereby limiting impacts on urban
waterways that are prone to erosion in more frequent storms.
Pollutants retention in stormwater treatment chambers. D. A. Phipps; R. M. Alkhaddar*+; M. G. Faram
Presented by Rafid Alkhaddar, Liverpool John Moores University, United Kingdom (Great Britain)
In recent years, various proprietary treatment technologies have evolved to reduce the polluting impact of urban run-off on receiving
watercourses. The majority are ‘flow-through’ devices, designed to intercept and store pollutants in submerged chambers for later
removal and safe disposal. Frequently, the performance of such systems is described solely in terms of ‘ability to remove pollutants
from the inflow’, usually at specified discrete flowrates. However, it is suggested that this is insufficient to give a true assessment of
performance and a critical parameter that is often overlooked is chamber ‘retention efficiency’, the ability of a chamber to retain
stored pollutants once collected. In the current study, this parameter is investigated experimentally for a range of chamber
configurations. Cylindrical chambers with different inlet orientations, internal components and hence flow dynamics are considered.
The study identifies retention efficiency as being a major differentiator between designs, and concludes that chambers in which
captured pollutants are stored in regions that are hydraulically isolated from the main treatment area are likely to be the most
effective in practice.
Stormwater quality as described in the National Stormwater Quality Database (NSQD). R.E. Pitt*+; A. Maestre
Presented by Robert Pitt, University of Alabama, United States of America
The University of Alabama and the Center for Watershed Protection were awarded a U.S. Environmental Protection Agency, Office of
Water 104(b)3 grant in 2001 to collect and evaluate stormwater data from a portion of the NPDES (National Pollutant Discharge
Elimination System) MS4 (municipal separate storm sewer system) stormwater permit holders. The initial version of this database,
the National Stormwater Quality Database (NSQD, version 1.1) is currently being completed. These stormwater quality data and site
descriptions are being collected and reviewed to describe the characteristics of national stormwater quality, to provide guidance for
future sampling needs, and to enhance local stormwater management activities in areas having limited data. The monitoring data
collected over nearly a ten-year period from more than 200 municipalities throughout the country have a great potential in
characterizing the quality of stormwater runoff and comparing it against historical benchmarks. This project is creating a national
database of stormwater monitoring data collected as part of the existing stormwater permit program, providing a scientific analysis
of the data, and providing recommendations for improving the quality and management value of future NPDES monitoring efforts.
Socioeconomic impacts on fluvial system an urban watershed in southern Brazil. C. Poleto*+; G.H. Merten; A.L.L. Silveira
Presented by Cristiano Poleto, Federal University of Rio Grande do Sul, Brazil
One of the great problems observed in the Brazilian urban watersheds concerns the amount of solid residues, domestic sewerage and
sediments that are disposed in the rivers and streams that drain these basins. The present work sought to evaluate these questions
through a study of case taken in an urban watershed in the metropolitan region of Porto Alegre, South of Brazil. For this study
different procedures have been used, such as field surveys, interviews with the inhabitants, use of satellite image and evaluation of
the morphology of part of the fluvial system of the basin to check the channel’s degree of instability. In the study area it was
verified that in the year of 2004, 37,10% of the watershed was impermeable, considering the paved streets, the residential and
commercial buildings and the stone pavements. As there is no sewer treatment, most of this sewerage is disposed directly into the
stream. Moreover, the occupation of riparian areas, the great amount of soil exposed in the watershed, the non-paved streets and
the great volume of solid residues are generating instability in the channel (it is silting of the stream bed). The socioeconomic
characteristics and the existing infrastructure conditions in the studied area allow us to conclude that this watershed is sufficiently
representative of the conditions presented in the periphery of the great Brazilian cities.
The hydraulic capacity of sewer system scanned by CCTV inspection. J. Pollert jun*+; R. Ugarelli; S. Saegrov
Presented by Jaroslav Pollert, CTU in Prague - Faculty of Civil Engineering, Czech Republic
Sewer and wastewater systems suffer from insufficient capacity, construction flaws and pipe deterioration. This paper presents the
results of a research developed inside the CARE-S project focused on sewer and storm water networks management.. Hydraulic
simulations are usually done running commercial models that apply, as input, default values of parameters that strongly influence
results. Using CCTV inspections data to cataloguefailures affecting pipes, a 3D model was used to evaluate their hydraulic
consequences. The translation of failures effects in parameters values producing the same hydraulic conditions caused by failures
was done through the comparison of laboratory experiences and 3D simulations results. A Visual Basic routine was developed in order
to automatically calculate the effects of temporal decline in terms of pressure drops in the system components: coefficients of local
or distributed head loss. Those parameters could be the input of 1D commercial models instead of the default values commonly
inserted. This will move the results from 1D models closer to reality and decrees a number of calibrations needs. It can be also used
during the operation time for changing performance capacity due to deduction of failures, or for prediction of capacity due to
predicted failures on a sewer system.
Simulations of flash floods in Marseille and Bordeaux with a two-dimensional runoff model. F. Pons; B. Zhang; P. Sergent*+; D.
Felts
Presented by Philippe Sergent, CETMEF, France
Recent tragedies of flooding in urban areas like Bordeaux (1982), Nîmes (1988) or Marseille (2000) have led stakeholders and
technicians to lean on this issue. Sewage systems for rainfalls are generally designed for events with a return period of ten years
whereas more severe events lead to runoff on the streets and unfortunately to damages of goods and sometimes human casualties.
This work aims at improving surface flow models in urban area through a project gathering several organizations from the French
Ministry of Public Works and scientists. Applications are made with this model on the catchment area of an urban district of Marseille
named Vieux-Port and on a district area of Bordeaux named La Grenouillère.
Experimental study of detention/infiltration trenches. A. Proton*+; B. Chocat
Presented by Antoine Proton, URGC, INSA Lyon, France
BMPs aim to reduce the flow of water and pollutants discharged by cities during rainy periods. Detention and/or infiltration trenches
are one of the techniques that can be used. Lack of knowledge as to the hydraulic functioning of such facilities still hinders their
use. The objective of the present research programme, carried out jointly by URGC, SOGEA Rhone-Alpes and Greater Lyon, is to
optimise trench design. The project is mainly based on an experimental study to test various types of trench. The present paper
describes the experimental system used to monitor the hydraulic performance of detention or infiltration trenches. The
experimental apparatus is independent of rainfall and can be operated in fully controlled conditions. Trenches are modelled using a
storage model. The first sets of data show that this kind of model seems to give good results.
Enhancement of oil retention and biodegradation in pervious pavements and infiltration systems. T. Puehmeier+; D. de Dreu;
J.A.W. Morgan; A. Shuttleworth; A. P. Newman*
Presented by Tim Puehmeier, Permavoid Ltd, United Kingdom (Great Britain)
This paper reports recent developments in oil trapping and oil biodegrading systems in pervious pavements and in infiltration systems
used in conjunction with non-pervious surfaces. The advances made in the technology and operation of pervious surfaces fitted with
an integrated oil water separator will be described. This involves a newly developed, floating mat system which serves to interact
with any oil which, in the event of a large spill, passes through the initial oil retaining structures of a pervious pavement or other
form of infiltration system. It also provides the ideal surface upon which the oil degrading organisms will thrive. The ability of these
enhanced systems to produce a diverse biodegrading bacterial/fungal community is reported. A further study will report a
comparison of biodegradation of new and used mineral oil trapped on these structures. The second area of research reported will be
associated with a novel oil separating system designed to be either coupled closely to an infiltrating filter trench which can be used
in conjunction with impervious surfaces or to direct the water back under an impermeable surface for further treatment, retention
and attenuation of flow. This system was shown to be highly effective in removing hydrocarbons and has the advantage that it can be
used as a retrofit solution to allow disconnection of existing impervious surfaces without exposing groundwater to contamination.
Growth of a toxic cyanobacteria in a retention pond. C. Quiblier; C. Yépremian; C, Berger; C. Bernard; A. Groleau; B.Vinçon-Leite;
B. Tassin*+
Presented by Bruno Tassin, Cereve /Ecole Natinale des Ponts et Chaussées, France
In this paper, a research project is presented. This project goals are mainly to identify the environmental factors (temperature,
nutrients, zooplankton,…) driving the development of a toxic cyanobacterium species (P. agardhii) and the variations of the toxic and
non-toxic clones, in a retention pond. The physico-chemical context, the phytoplankton dynamics and the toxin production have
been monitored by a fortnightly field survey, whose preliminary results are presented.
The integrated unit process design approach for source control and best management practice design. M.M. Quigley*+; E.W.
Strecker; M. Leisenring; W.C. Huber; J. Heaney; N. Weinstein; J. Sansalone; D. Bodine
Presented by Marcus Quigley, Geosyntec Consultants, United States of America
Research being conducted by the authors under the National Cooperative Highway Research Program project “Evaluation of Best
Management Practices for Highway Runoff Control” and the Water Environment Research Foundation project “Critical Assessment of
Stormwater Treatment and Control Selection Issues“ seeks to advance the state of the practice of stormwater design through the
application of basic scientifically and technically sound engineering principals using a fundamental unit process design methodology.
The research findings are being incorporated into guidance manuals aimed at both the design of highway runoff controls and, in the
case of the WERF guidance documents, stormwater treatment approaches. The intent of these manuals is to provide a means for
better applying research on the relationship between design and performance specifically emphasizing the importance of matching
water quality goals to fundamental unit processes. To that end, the research discussed in this paper has integrated findings from a
number of sources including work by the authors conducted as part of the International Stormwater Best Management Practices
Database project as well as the above referenced projects. The paper pays particular attention to elucidating the current state of
the practice relative to the availability of sources of performance information.
Rapid WWTP performance evaluation over a wide range of operating conditions using artificial neural networks. B. Ráduly*+;
K.V. Gernaey; A. G. Capodaglio; P. S. Mikkelsen; M. Henze
Presented by Botond Ráduly, University of Pavia, Italy
Wastewater treatment plants (WWTPs) are an essential component of the integrated urban water system. The simulation of the
plants behaviour is becoming an essential tool for design, evaluation and everyday operation of the plants. Rather long influent time
series containing a wide range of influent disturbances are needed to allow a simulation-based WWTP performance evaluation of
sufficient quality, but this in turn requires long simulation times. The approach proposed in this paper combines an influent
disturbance generator with a deterministic WWTP model for generating a limited sequence of training data (6 months of dynamic
data). An artificial neural network (ANN) is then trained on the available WTTP input-output data, and is subsequently used to
49
simulate the remainder of the influent time series (20 years of dynamic data) generated with the influent disturbance generator. It is
demonstrated that the ANN reduces simulation time by a factor of 17, even when including the time needed for ANN training. ANN
prediction of effluent BOD5 and total suspended solids was good when compared to deterministic WWTP model predictions
(correlation coefficient > 0.95), whereas prediction of effluent ammonium and total nitrogen concentrations was less satisfactory
(correlation coefficient > 0.70).
Study of the water budget of streets: experimentation and modelling. D. Ramier*; E. Berthier; H. Andrieu+
Presented by Hervé Andrieu, Laboratoire Central des Ponts-et-Chaussées, France
The study of two stretches of street during 38 months allowed to analyze the hydrological behavior of streets during rain events. The
results show that runoff coefficients are very variable and runoff losses may be important. In order to better understand this
behavior, a physical based model is used. This model, BiL, combine a porous media flow module with a surface runoff module. The
lateral runoff transfer in the lateral gutter is approximated by the Muskingum model. Evaporation is simulated by an adaptation of
the Penman’s method. A sensitivity study showed that the model is mainly sensitive to saturated hydraulic conductivity of the
asphalt pavement and to the storage capacity. The comparison of simulated and observed data gives good results for the runoff
outflow at a 3 minutes time step. On the other hand, the simulation results are less encouraging for the runoff coefficient. This study
of the water budget of two street stretches during a period of 38 indicates that the infiltration and evaporation represent between
20 and 30 % of rain.
From point to areal rainfall: linking the different approaches for the frequency characterization of rainfalls in urban areas. M.H.
Ramos*+; E. Leblois; J.-D. Creutin
Presented by Maria Helena Ramos, Cemagref, France
In urban water design and management, many hydrologic problems involve the frequency characterization of rainfalls. Hydrologists
are commonly asked to evaluate rainfall intensities for given recurrence frequencies or to indicate how rare an observed event is by
estimating its return period. This study aims to improve the characterization of rainfall hazard over a city by linking point to areal
rainfall frequency analysis. We use a stochastic rainfall field generator based on the turning-bands method to directly assess areal
rainfall distributions and to illustrate the link between different approaches. The simulating algorithm is applied to rainfall data from
the city of Marseilles. The frequency analysis of simulated fields provides the elements to deal with the notions of return period and
severity of observed storm events. The study concludes on the importance of a unified approach to better assess rainfall.
Removal of dissolved metals by zero-valent iron(ZVI): Kinetics, equilibriums, processes, and implications for stormwater runoff
treatment. R. Rangsivek*+; M. R. Jekel
Presented by Ropru Rangsivek, Technical University of Berlin, Germany
This study investigates the processes of copper and zinc ion removal from stormwater runoff by zero-valent iron (ZVI, Fe0). Kinetic
and equilibrium tests were performed with laboratory prepared and in-situ stormwater runoff samples collected from roof, street
and highway catchments. Based on the results, a substantial portion of Cu2+ is reduced and transformed to insoluble forms of Cu0
and Cu2O. Unlike wise, the adsorption and co-precipitation associated with freshly precipitated iron oxides play important roles for
the removal of Zn2+. Investigations under various water quality conditions prevailed relative minor impacts on Cu2+ uptake rates.
However, they apparently altered the removal stoichiometry and phases of copper deposits. The removal rates of Zn2+ increase with
higher dissolved oxygen (DO), ionic strength (IS), temperature (T) and pH. Dissolved organic carbon (DOC) in runoff samples forms
complexation with metals and Fe2+, thereby, kinetically decreases the metal uptake rates. Furthermore, depending on its
composition, a larger molecular weight organic fraction was found to compete for the adsorption sites. The study demonstrates ZVI is
a promising media achieving comparable capacity to a commercial adsorbent like Granular Ferric Hydroxide (GFH). Long-term
performances of ZVI, however, may be limited and governed by the formation of non-conductive layer of iron and cuprous oxides.
On the issue of trend and noise in the estimation of extreme rainfall properties. W. Rauch+; S. De Toffol*
Presented by Wolfgang Rauch, University Innsbruck, Austria
Up until today extreme rainfall properties are frequently applied in sewer design guidelines. Uncertainty in the estimation of such
properties will hence directly influence the dimensions of sewers, structures and pumps. In this paper the issue of potential trend
and noise in the estimation is investigated for 6 rain series from ranging from 19 to 55 years in duration. Different to recent research
that predicts a - climate induced – increase in heavy precipitation no clear indication for such trend was found in the investigated
historical rain series. Another important aspect is the length of the rain series that is required for the estimation of the extreme
rainfall property and the associated uncertainty. The analysis indicates that at least a period of 10 years should be used for the
estimation. But even so the possible deviation expressed in terms of the 90 percentile is in the order of 5 to 10% of the ‘true value’,
defined as the value derived when the whole given series is used for the estimation.
PAH and metals in snow along a highway. K. Reinosdotter*+; M. Viklander; P. A. Malmqvist
Presented by Karin Reinosdotter, Luleå University of Technology, Sweden
Snow quality and its variations due to distance from the road were studied. Also, how the snow quality changes over time during the
melting period was discussed. Snow samples were collected at three occasions during the winter of 2004. The samples were taken
along a highway in the Luleå region, Sweden, with an average daily traffic load of 9200 vehicles. Snow samples were taken
perpendicular to the road and at different distances. The snow samples were analyzed for metals and PAH. Also, weather parameters
such as temperature, precipitation, and wind speed and wind direction were measured. The highest total metal and PAH
concentrations were found at the sample site closest to the road and at the end of the season. Before the melting period started, 4257 % of the total amount of metals and PAH were found in the first 1m of the snow pack. This information could be valuable when
one is discussing how to achieve a sustainable snow-handling management.
Assessment of the exchanges between sewage network and surface water during flooding of the town of Oullins. E. Renouf; A.
Paquier*+, E. Mignot
Presented by André Paquier, Cemagref, France
Oullins is a small city that suffers frequent flooding either from Yzeron River overflow or from the sewage network overflows during
storm event. In December 2003, both causes join to provoke severe damages in the lower part of the city. Two models were built.
One simulates the flows in the sewage network solving 1-D de Saint Venant equations. The second one, solving 2-D shallow water
equation, represents Yzeron main channel and associated flood plain that extends over the lower part of Oullins both on left and
right banks. The two models are independently calibrated. Coupling between these two models is performed in order to examine if
an accurate representation of the exchanges between sewage flows and surface flows could improve the simulation of the 2003's
flood. The final aim of the study will be the design of the works to improve the operation of the sewage network during an event
similar to the last flood.
Using decision analysis to determine optimal experimental design for monitoring sewer exfiltration with tracers. J.
Rieckermann*+; M. E. Borsuk; W. Gujer
Presented by Jörg Rieckermann, EAWAG, Switzerland
The tracer methods developed to assess exfiltration from sewers in the European project APUSS (Assessment of the Performance of
Sewer Systems) have a high degree of freedom with regard to the choice of tracer and the dosing strategy. These can lead to very
different degrees of uncertainty in the measured exfiltration ratio. In this study, we demonstrate how to select an optimal
experimental design using decision analysis, which accounts for this uncertainty and its associated costs. Although the results are
site-specific, we can conclude generally that, when NaCl is used as the tracer, the accuracy of the exfiltration estimate is most
sensitive to the amount of tracer used and the starting time of the experiment.
Stormwater source control as a strategy for sustainable development: State of the practice and perceived trends. G. Rivard*+;
G. Raimbault; S. Barraud; G. Freni; B. Ellis; M. Zaizen; R. Ashley; M. Quigley; E. Strecker
Presented by Gilles Rivard, Aquapraxis inc., Canada
The primary objective of the paper is to draw upon the experiences acquired in many parts of the world to provide an up-to-date
summary of the state of the practice for source control techniques and approaches, in a sustainable development context. After a
discussion of the prevailing context for urban drainage approaches, three main themes covering techniques and design criteria,
institutional aspects and performance issues are discussed relative to source control implementation. The discussion is based on
findings from the compilation and analysis of available literature, recently developed databases, the experience of the different
members of the SOCOMA group and recent research on design methodologies that explicitly seek to better couple effective design
and achievement of performance goals. The paper also discusses perceived trends in the selection, analysis, and implementation of
source controls, highlighting the areas where knowledge is lacking and providing recommendations on needs for future research.
An analytical model for hydrologic analysis in urban watersheds. P. Rivera; J. Gironás*+; J. P. Montt; B. Fernández
Presented by Jorge Gironas, CSU, United States of America
Guo and Adams (1998a, b) presented a methodology to estimate the cumulative distribution function for maximum discharges and
total volumes of urban floods based on the rainfall-runoff transformation and the rainfall volume and duration, modeled as
independent variables exponentially distributed. Rainfall records in many locations did not show this independency; therefore this
model may fail at estimating these distributions. In this paper a new analytical model based on a different characterization of the
storms is presented. In order to represent the dependence between rain volume and duration, the average intensity and duration are
modeled as independent variables exponentially distributed. The present approach includes the theoretical probability distributions
for the storms, the mathematical functions used in the developing of the analytical model, and the probability distribution for runoff
volumes and peak discharges. Good results are obtained in comparison with those from continuous SWMM simulations. Modifications
of the typical watershed parameters and the respective effects and results using the model proposed by Guo and Adams, are also
presented.
Flooding flows in city crossroads: experiments and 1D modelling. N. Riviere*; R. J. Perkins+; B. Chocat; A. Lecus
Presented by Richard Perkins, Ecole Centrale de Lyon, France
This study focuses on the discharge distribution in an intersection of four channels, similar to a city crossroad. The channels and the
intersection are all horizontal. Flow enters through two of the channels, and leaves through the other two. The flow is subcritical
everywhere, and flow depths are controlled by vertical weirs at the exits of the outlet channels. The main variables that are
measured are the flow rates in the four channels. When the weir heights in the outlet channels are the same, the ratio of flowrates
in the outlet channels depends only on the ratio of flowrates in the inlet channels; if the outlet conditions are different, other
parameters, such as the total flow rate also become important. The flow has also been simulated numerically using a solution of the
1-D St. Venant equations, with a simple model to predict flow distribution in the intersection. A comparison with the experimental
data shows that this model works well for the limited range of experimental conditions studied here. However further work is
needed on a wider range of conditions, closer to real conditions, before the model can be considered valid for practical applications.
Pervious pavement research in Spain: structural and hydraulic issues. J. Rodríguez*+; D. Castro, M. A. Calzada, J. W. Davies
Presented by Jorge Rodríguez, Universidad de Cantabria, Spain
This paper describes part of a new programme of research into the performance of pervious pavement structures in Spain. The
project is collaboration between University of Cantabria and Coventry University and it tries to introduce the use of pervious surfaces
in Spain at the same time as innovating these techniques. An experimental study of the structural and hydraulic effectiveness and
suitability of different materials for the pervious surface (concrete blocks, porous asphalt and porous concrete) and the sub-base
(limestone, recycled concrete and mixes with recycled plastic) is being carried out considering their ability to support the
microbiological communities for the biodegradation, including the study of geotextiles and their ability to retain humidity during dry
periods. This research is taking place under weather conditions corresponding to the North of Spain, an area with excellent potential
for introduction of all kinds of SUDS. Work is being carried out in the laboratory and at field sites in Gijon and Santander. The paper
presents initial results on the hydraulic performance of two different concrete blocks and their clogging tendency under differing
conditions of slope, silt and rain. These lead to initial conclusions on design, lifespan and maintenance needs.
Physical effects of wet weather discharges on aquatic habitats - Present knowledge and research needs. L.A. Roesner*+; B.P.
Bledsoe; C.A. Rohrer
Presented by Larry Roesner, Colorado State University, United States of America
This study explores the current state of knowledge with respect to the effects of wet weather flows from urban areas on the physical
character of aquatic habitat. It identifies knowledge gaps with respect to our ability to define the cause-effect relationships,
examines the comprehensiveness of the data used in support of the published literature in the subject area, and makes a qualitative
determination of the usefulness of those data for further analysis to increase our knowledge in the subject area. Finally, it
recommends further research studies that will increase our knowledge in the subject area, with emphasis on pilot-scale projects that
can be used to develop practical protocols for preventing or mitigating the effects.
Real-time control of the integrated urban drainage system in the city of Leipzig. R. Rohlfing*+; C. Nietzschmann; M. Wiemann
Presented by Richard Rohlfing, PFI Umweltconsult, Germany
The existing sewer network of the City of Leipzig (Germany) is characterized by old brick sewer pipes. The objective of the old part
of the drainage system consists in the rapid discharge of stormwater to the numerous outlets of the network. In the given system,
even small storm events cause combined sewer overflows (CSOs). About 80 % of all combined sewer overflows occur at the overflow
structure at the inlet of the treatment plant or at the first outlets upstream the treatment plant. The intended maximum pollution
load into the receiving waters was exceeded significantly. Options for construction and activation of storage capacity applying realtime control within the sewer network were investigated. At the same time, the rehabilitation of the treatment plant was planned.
This provided a good opportunity for an optimisation of both parts of the drainage system. A total emission concept was used for the
optimal design of the storage capacity of the network and for the rehabilitation of the treatment plant taking into account real-time
control. For the reason of flood protection, water pollution control and support of the treatment plant processes, control structures
51
have to perform multiple objectives. This has to be done using integrated real-time control. With the given example of the urban
waste water system (sewer system, treatment plant, water bodies) in the city of Leipzig, it is demonstrated in which way the
integrated control system was designed.
Matching the critical portion of the flow duration curve to minimize changes in modeled excess shear. C.A. Rohrer*+; L.A.
Roesner
Presented by Christine Rohrer, Colorado State University, United States of America
Hydrologic and hydraulic modeling in the USEPA Stormwater Management Model (SWMM) were used to examine the effectiveness of
typical stormwater management practices in reducing the potential for stream erosion. Fifty-year continuous simulations were used
to produce flow duration curves and stream erosion rates for a variety of critical shear stress values representative of both cohesive
and non-cohesive sediments. An excess shear stress erosion potential index was used to evaluate changes in erosion between
undeveloped conditions of a 10 hectare watershed and four variations of post-development stormwater control. Evaluation of flow
duration curves showed that when development takes place the duration of mid- to low-range discharges increase significantly,
especially when detention practices are applied. In channels with low entrainment thresholds for bed and bank materials, e.g., sands
and highly erodible clays, the significant increase of the duration of mid- to low-range discharges results in erosion potential index
values greater than two regardless of the detention practices used. Overcontrol detention resulted in erosion potential index values
of less than one, indicating a loss of erosion potential for bed materials such as most gravels (ds > 6 mm) and resistant clays that
have critical shear stress values greater than four Pa.
Water quality criteria for total suspended solids (TSS) in urban wet-weather discharges. L. Rossi*+; R. Fankhauser; N. Chévre
Presented by Luca Rossi, EAWAG, Switzerland
Total suspended solids (TSS) from combined sewer overflows (CSOs) and stormwater discharges represent a crucial parameter for
evaluating wet-weather pollution in urban areas. In fact, the increase of TSS in water during rain events can have ecotoxic effects on
aquatic organisms. Furthermore, major potentially harmful substances such as heavy metals, PAHs and organic matter are adsorbed
onto TSS and later settle on sediment. Water quality criteria for TSS consequently enable the risk of wet-weather pollution to be
assessed, for instance to avoid detrimental effects on aquatic organisms. The criteria proposed in this study cover the short-term
impact of TSS on fish (acute quality criteria AQC), taking into account the duration of their exposure in the receiving water. The
concentration-exposure duration-effect curve proposed here thus predicts “ill effects” on fish for different exposure times and TSS
concentrations. The ecotoxic effects of adsorbed pollutants are also taken into account with an additional safety factor. We
implement this TSS criteria in a software that allows us to estimate the number of rain events that exceed a given morbidity
threshold for fishes per year.
SWMM5: The USEPA’s newest tool for urban drainage analysis. L.A. Rossman; R.E. Dickinson; T. Schade; C. Chan; E.H. Burgess;
W.C.
Huber*+
Presented by Wayne C. Huber, Oregon State University, United States of America
A new version 5.0 of the United States Environmental Protection Agency (USEPA) Storm Water Management Model (SWMM) has been
developed. Its computational engine has been completely re-written using an object-based approach. It also has a Windows graphical
user interface that allows users to create and edit system components directly on a map of the catchment area and view the results
of simulation runs in a variety of formats. SWMM 5 contains several computational enhancements, such as improvements to its
dynamic wave flow routing routine, support for user-defined rules for real time operational control, and user-defined treatment
functions. A utility is also included for converting old SWMM data sets into the new SWMM format. The complete package, including
new documentation and full source code, is available at no charge from the USEPA web site: http://www.epa.gov/ednnrmrl/swmm.
Daily patterns of micro-organisms in the foul sewer system of Doncaster, United Kingdom. J. Rueedi*+; A.A. Cronin; B.L. Morris
Presented by Joerg Rueedi, University of Surrey, United Kingdom (Great Britain)
Much is known about short-term changes in sewage volumes because they are often measured in pipeline design studies. Usually,
sewage volumes peak in the morning and again in the evening, and leakage rates are expected to change correspondingly. To assess
the contaminant load leaking into the subsurface, however, it is important to know the daily evolution of contaminant
concentrations. These data are scarce, particularly for pathogenic micro-organisms. This study describes results of raw sewage
sampling at three pumping stations for total coliforms, faecal coliforms, faecal streptococci, sulphite-reducing clostridia, coliphage
and enteric viruses. The results show that all analysed micro-organisms follow a similar daily pattern, namely high concentrations
during the morning, dropping around noon, rising again during the afternoon and then falling again in the evening and nighttime.
Concurrent measurement of sewage volumes enabled assessment of total contaminant loads leaving the urban area, estimation of
likely daily patterns of toilet/grey water contribution to raw sewage and calculation of daily average loads for urban mass balance
modeling. The paper shows how important it is to measure not only daily patterns of sewage volumes but also sewage concentrations
because both vary significantly during the day due to different household usage patterns.
Comparative study among different methodologies to determine storm sewer inlet efficiency from test data. B. Russo; M.
Gómez*+
Presented by Manuel Gomez, UPC - ETS ING. CAMINOS, Spain
Storm drain inlets are used to collect urban runoff and discharge it to an underground sewer system. Inadequate attention to inlet
capacity can cause undue hazard to the security of many urban activities. Several agencies and manufacturers of grates have
investigated inlet grate interception capacity by hydraulic tests. Actually the reference in this field is the Hydraulic Engineering
Circular No.12 published by U.S. Department of Transportation; it describes a semi-theoretical method for estimating inlet efficiency
but was elaborated for some different types of grates and its use is limited to these ones. Recently Neenah Foundry Company, in its
recent catalog, presented a research project about inlet grate capacity but this methodology suffers from the same restriction. The
Hydraulic Department of the Technical University of Catalonia started a new research line in the field of inlet hydraulics and one of
the goals was the finding of a formula usable for each type of grate and street geometry, even that could be applied to inlets not
previously tested but similar to those used in the experimental campaign. A comparative study among these methodologies was
carried out and it was demonstrated the similarity of the results in terms of efficiency.
Methodology to study the surface runoff in urban streets and the design of drainage inlets systems. Application in a real case
study. B. Russo*+; M. Gómez; P. Martínez; H. Sanchez
Presented by Beniamino Russo, Technical University of Catalonia, Spain
Barcelona is located in the Mediterranean area in the North of Spain and this increases its hydrological problems concerning urban
environment. Recently a big effort has been done to increase the capacity of the city sewers but still there are flood problems
although the sewer capacity shows to be enough. This is the case of the North Bus Station area. The aim of this study was to solve
the problems concerning the frequent floods in this area so a specific hydraulic analysis based on a simulation modeling of the
behavior of the pipes was carried out. The results of the simulation showed that local pipes had sufficient capacity and floods were
caused by a lack of inlets. To avoid floods it was necessary to design a correct drainage system in the whole urban basin. The
hydraulic behavior of the involved streets was analyzed with HECMOD. According to a design storm, it was calculated the number of
necessary inlets to fulfill the risk criteria associated to the surface runoff. Finally it was possible to know the flow evolution in this
catchment and the related values of some hydraulic parameters (water depth and velocity) responsible for the security of pedestrian
and vehicular circulation.
Bacterial loading in the water of urban streams in Helsinki, Southern Finland. O. Ruth*+
Presented by Olli Ruth, University of Helsinki, Finland
Little research has been done into the hygienic quality of urban waters in Finland, and virtually none during the winter, when smaller
streams are covered by ice. This paper presents data on three urban streams in Helsinki compiled at weekly intervals throughout the
year in the periods 1995-96 and 1998-99. The results suggest that water quality varies greatly between winters according to weather
conditions, with fairly large quantities of bacteria passing into the streams with the melt water in mild winters, while water quality
remains good in frosty winters. Bacterial loading was highest in summer in all cases, however, and counts of hygienic indicator
bacteria in these streams in Helsinki were on average 10-20-fold and momentarily several hundred-fold relative to those in areas in a
natural state, although concentrations were low relative to those in actual storm water. The majority of the bacterial loading was
found to originate from the excrement of warm-blooded animals, particularly dogs and birds. The easiest way of improving water
quality in the streams of Helsinki would be to draw the attention of dog owners to the problem and ensure more efficient removal of
dog excrement from the streets.
Quantification of sewer exfiltration - a review. M. Rutsch*+; J. Rieckermann; P. Krebs
Presented by Mandy Rutsch, Dresden University of Technology, Germany
One of the goals of the APUSS project (Assessing Infiltration and Exfiltration on the Performance of Urban Sewer Systems) is to assess
sewer exfiltration, in order to support cities and operators to define problem-oriented rehabilitation strategies. In this paper, we
review various methods currently used for the estimation of exfiltration and discuss data needs and applicability for rehabilitation
planning. Although, each approach has its individual advantages and drawbacks, we identified pressure tests and tracer methods to
have the highest potential for decision support in rehabilitation planning. With regard to future challenges (e.g. micro pollutants)
such methods might play a key role in integrated sewer management.
New Goals and Strategies for CSOs Control from Legal Aspect. T. Sakakibara*+; T. Masuta; M. Matsubara; S. Kato
Presented by Takashi Sakakibara, Saitama City Government, Japan
This paper describes the new goals and strategies for Combined Sewer Overflows (CSOs) control in Japan, shows the amendment of
Enforcement Order of Sewerage Law which support the CSOs control in legal aspect. Under the “CSO control studying Committee”,
established by Ministry of Land Infrastructure and Transport in 2001, new goals for CSOs were proposed: i) to reduce the overflow’s
pollutants loads under the level of Separate Sewer System. ii) to halve the overflow events from stormwater outlets to satisfy secure
in terms of public health. iii) to eliminate the debris. To meet these goals, the comprehensive strategies as follows were built up: i)
create guidelines and monitoring manual for planning tools. ii) start urgent program and project with financial support. iii) progress
special research and development project “SPIRIT21”. iv) amend the Enforcement Order of the Sewerage law as legal support for
goals. In the contents of this amendment, following items were stipulated for CSOs control. i) wet weather water quality standard
for CSOs should be less than 40mg/l. ii) structure of weir at stormwater outlet. iii) installation of screen to eliminate the debris. iv)
monitoring CSOs at least once a year for BOD. v) interim measures.
Characterisation of urban stormwater runoff from separated sewer overflows in Luxembourg. M. Salvia-Castellvi*+; J. F. Iffly; C.
Guignard; L. Pfister
Presented by Mercè Salvia-Castellvi, CRP-Gabriel Lippmann, Luxembourg
Separated sewer overflows (SSOs) are well known for their overflows of untreated water during storm events. In this study, a total of
22 storms was surveyed in two separated sewer systems in the town of Luxembourg during the period from August 2003 to February
2004. For each storm event, both runoff and quality parameters were analysed. Inter-storm and intra-storm variability were
determined for both sewers, and the relationships between Event Mean Concentrations (EMC) and runoff patterns analysed. The
magnitude of the first flush effect was calculated through the dimensionless curves representing the variation of the cumulative
pollutant mass ratio in relation to the cumulative volume ratio. The presence of illicit sanitary inputs in one of the sewers produces a
significant first flush effect in its storm runoff as well as higher EMC for all the pollutants related to suspended solids.
Integrating on-site water management practices: A field study in Prince George's County, Maryland. T. Saravanapavan*; L.
Shoemaker; J. Zhen; A. Davis; M. Clar+; S. Meigs; M. Cheng.
Presented by Michael Clar, Ecosite, Inc., United States of America
Decentralized and integrated stormwater management is becoming an efficient alternative to conventional “centralized” structural
Best Management Practices (BMPs). Decentralized management techniques, targeted to provide infiltration and minimize runoff
closer to the sources, not only meet the stormwater control targets but also maintain the natural ecosystem integrity. On the other
hand, conservation and reuse of rainwater and grey water are also emerging as environmentally sensitive “green” architectural
techniques. Although both stormwater management and green architecture techniques have similarities, the disciplines have had
limited interaction in practice. This study takes a holistic approach to site-level water management by examining both in-home and
on-site water management concurrently. The analysis was performed on a demonstration site location in Bowie, Maryland, USA that
is representative of single family home. A comprehensive site characterization and evaluation of water uses were performed. Water
use profiles for the site potable water, grey water, wastewater, rooftop runoff, and stormwater were evaluated to understand the
opportunities and alternatives for integrated stormwater management. A number of alternative scenarios were screened through
technical, economical, and social feasibilities and potential alternatives were recommended. The study demonstrates the capability
and benefits of integrating stormwater, potable water, grey water and wastewater available at the site.
Performance evaluations of storm tanks. A.J. Saul*+; J.R. Blanksby; W.J. Shepherd; C. Barker; M. Tillotson
Presented by Adrian Saul, Pennine Water Group, University of Sheffield, United Kingdom (Great Britain)
Storm tanks at WwTW are an essential but often neglected component of the sewerage system in terms of pollutant retention and
the subsequent impact of the pollution that is discharged from tanks to receiving waters. From an integrated catchment viewpoint
this component of spilled flow is a key element in the process. It may be argued that, in recent years, the design philosophy for
storm tanks has been static, certainly in the UK, and has not moved forward in the same way as other developments associated with
integrated quantitative and qualitative modelling of sewer systems and the performance of other ancillary structures. It is common
practice for the pollution retention performance of storm tanks to be omitted from regulatory guidelines and hence there is little
need to understand what is actually spilled to the receiving water. This paper describes a review of current practice and, based on
the findings of a UKWIR research project WW22B, presents a potential methodology that may be used to better understand the
hydraulic and pollutant retention performance of storm tanks.
Uncertainties related to extreme event statistics of sewer system surcharge and overflow. K. Schaarup-Jensen*+; C. Johansen; S.
Thorndahl
Presented by Kjeld Schaarup-Jensen, Aalborg University, Denmark
53
Today it is common practice - in the major part of Europe - to base design of sewer systems in urban areas on recommended
minimum values of flooding frequencies related to either pipe top level, basement level in buildings or level of road surfaces. Thus
storm water runoff in sewer systems is only proceeding in an acceptable manner, if flooding of these levels is having an average
return period bigger than a predefined value. This practice is also often used in functional analysis of existing sewer systems. If a
sewer system can fulfil recommended flooding frequencies or not, can only be verified by performing long term simulations - using a
sewer flow simulation model - and draw up extreme event statistics from the model simulations. In this context it is important to
realize that uncertainties related to the input parameters of rainfall runoff models will give rise to uncertainties related to the
corresponding extreme event statistics. This paper illustrates this problem in a case study with two different values of one input
parameter - the hydrological reduction factor - in two otherwise identical operations of the MOUSE LTS model. The use of a long
historical rainfall time series makes it possible to draw up extreme event statistics covering return periods of as much as 33 years. By
comparing these two different extreme event statistics it is evident that these to a great extent depend on the uncertainties related
to the input parameters of the rainfall runoff model.
The real issues with in-ground SUDS in Scotland. W. Schlüter*+; C. Jefferies
Presented by Wolfram Schluter, RPS-MCOS, Ireland
The aim of this research was to produce enhanced detailing and improved operation of in-ground SUDS. Data from on-site monitoring
at three filter drain and three infiltration trench systems were analysed and the results were combined with information gathered
from 40 assessments of in-situ systems in Eastern Scotland. Current findings showed that almost 50% of all systems were found to be
unsatisfactory and more than half of these were rated as having failed. 36% provided fair and 16%, good performance. Only one
system was considered to be performing excellently. Several reasons were identified for the poor performance. The principal cause
of problems was runoff from unstabilised areas or construction runoff, which was found to be affecting the systems’ longevity.
Almost 30% of all sites were affected by construction runoff. Another major problem was related to system maintenance since
maintenance programs were generally not in place. This study has shown that regular maintenance is vital for the longevity of inground SUDS.
Extreme storm events in combined sewer overflow analysis. T. G. Schmitt*+
Presented by Theo Schmitt, University of Kaiserslautern, Germany
The public awareness has related increased flooding events to climate change. The chance of more frequent extreme storm events
would heavily affect urban drainage systems and their performance in terms of both urban flooding and pollution load discharges.
The paper outlines CSO design and performance criteria for combined sewer systems. The significance of extreme storm events is
further analysed applying long-term pollution load simulations for two urban catchments of different characteristics. Simulation
results firstly illustrate the high variability of annual data in relation to long-term average overflow characteristics. Secondly,
extreme storm events are identified to significantly contribute to annual CSO discharge and overflow duration. Two to three
overflow events might add up to more than 50 % of annual overflow volume and load. Comparing a more rural drainage system with a
downtown catchment area indicates an even greater impact of extreme events in case of drainage systems with large storage volume
and a low level of CSO discharge. It is concluded that CSO performance criteria based on long term annual data is superior to single
event data. Furthermore, providing extra storage volume to existing CSO tanks, does not promise efficient reduction of CSO
activities.
The scope of integrated modeling - system boundaries, sub-systems, scales and disciplines. T.G. Schmitt*+; W. C. Huber
Presented by Theo Schmitt, University of Kaiserslautern, Germany
Integrated modeling has become an urgent issue of urban drainage and wastewater treatment planning. The scope of integrated
modeling, system boundaries and disciplines to be involved are addressed in view of future developments and new paradigms in
urban drainage, demanding the inclusion of the full urban water cycle. A system analysis is demonstrated to identify relevant subsystems and components, processes and interactions within the urban water system. The permissibility to exclude subsystems or
neglect interactions is evaluated. Integrated modeling of urban water system is characterized as an ambitious task in regard to
system complexity, heterogeneous scales and interface problems. The methodical status quo is characterized in preliminary
approaches towards integrated modeling. It is concluded that it does not seem promising to create and apply one entity model for
the scope of integrated urban water modeling. Instead, the development of adequate and efficient IT frameworks is identified as the
key issue of integrated modeling. Harmonizing interfaces to facilitate the linking of existing models is presented as the objective of a
European research project HarmonIT and the U.S. EPA Multimedia Integrated Modeling System project MIMS.
Application of case-based reasoning to support the management of experimental constructed wetlands treating gully pot liquor.
M. Scholz*+; B. H. Lee
Presented by Miklas Scholz, The University of Edinburgh, United Kingdom (Great Britain)
The aim was to predict the treatment efficiencies for gully pot liquor of experimental vertical-flow constructed wetland filters
containing Phragmites australis (Cav.) Trin. ex Steud. (common reed) and filter media of different adsorption capacities. Six out of
twelve filters received inflow water spiked with metals. For two years, hydrated nickel and copper nitrate were added to sieved
gully pot liquor to simulate contaminated primary treated storm runoff. For those six constructed filters receiving heavy metals, an
obvious breakthrough of dissolved nickel was recorded after road salting during the first winter. However, a breakthrough of nickel
was not observed since the inflow pH was raised to eight after the first year of operation. During the C°second year, reduction
efficiencies of heavy metals, five-day @ 20 N-Allylthiourea biochemical oxygen demand (BOD) and suspended solids (SS) improved
considerably. Concentrations of BOD were frequently <20 mg/L, an international threshold for secondary wastewater treatment. This
is likely due to biomass maturation and the increase of pH. Case-based reasoning (CBR) was applied to predict BOD and SS, and to
demonstrate an alternative method of analyzing water quality performance indicators. The CBR method was successful in predicting
if outflow concentrations were either above or below the thresholds.
The Glasgow Sustainable Urban Drainage System Management Project. M. Scholz*+
Presented by Miklas Scholz, The University of Edinburgh, United Kingdom (Great Britain)
‘The Glasgow Sustainable Urban Drainage System (SUDS) Management Project’ satisfies the first of three phases of the ‘Glasgow
Surface Water Management Project’. This is Glasgow City Council’s contribution to the Transformation of Rural and Urban Spatial
Structure (TRUST) project, one of the European Union’s (EU) inter-regional (INTERREG IIIB) North Sea funded research projects. This
project shows also how SUDS can contribute to the overall catchment dynamics of cities such as Glasgow, ultimately relieving stress
on the current predominantly combined sewer system, and increasing the urban habitat value at the same time. Fifty-seven sites
within 46 areas of Glasgow were identified for assessment. A detailed soil chemistry analysis and a desk study relating to ecological,
historical and current (regeneration and development) planning issues were undertaken. Detailed design guidelines were then
drafted for seven selected representative demonstration areas (including the Gadburn area) of high public and property developers
interest, and education value. A SUDS option decision support tool was developed to help the planners to suggest appropriate SUDS
techniques for potential construction sites based on site characteristics (SUDS variables). A combination of swales with ponds or
wetlands were the most likely SUDS options for the majority of the demonstration areas.
Integrated Simulation of the Berlin Sewage System and Evaluation of a global Real-time Control Concept. K. Schroeder*+; R.
Mannel; E. Pawlowsky-Reusing; J. Broll
Presented by Kai Schroeder, KompetenzZentrum Wasser Berlin gGmbH, Germany
The paper presents the build-up of a model for the integrated simulation of the sewage system of Berlin, Germany, focusing on the
catchment of the wastewater treatment plant Ruhleben. The Ruhleben catchment, draining 185 km² and a population of 1.38 million
inhabitants is characterised by its high portion of combined sewerage. The model comprises the collection system, pump stations,
pressurised mains and the wastewater treatment plant. Hydraulic and quality processes are taken into account. A preliminary
assessment of the sewage system and the analysis of historical operational data showed a high potential concerning global real-time
control of the pump stations. Three different global control scenarios have been studied on the basis of a long time simulation over
50 days and compared with a local control regime. The results show that the coordinated operation leads to a reduction of total
emissions. Main improvements can be achieved concerning the discharges from combined sewer overflows. These improvements are
of major significance due to the high hazard potential of combined sewer overflows.
A general algorithm for the development of control algorithms for RTC of sewer systems. M. Schütze*+; J. Alex; M. Ogurek.
Presented by Manfred Schuetze, ifak Magdeburg e. V., Germany
Despite the large number of publications on the topic of real time control (RTC) of urban drainage systems, there are, however, only
few indications on how a control algorithm for a particular case study is actually determined. Often, this involves an time-consuming
and costly heuristic procedure, based on the expertise and intuition of the person carrying out such study. This paper presents a
generic procedure for the set up of RTC strategies. Essentially RTC control actions are expressed as a function of known input
variables (e.g. water level measurements). Using a hydrologic simulation model, developed under the SIMBA platform, the procedure
is tested on two examples and shows to be successful in finding a good RTC algorithm.
New guidelines for planning of real time control for urban drainage systems. M. Schütze*+; U. Haas; M. Scheer; W. Schilling
Presented by Manfred Schuetze, ifak Magdeburg e. V., Germany
Recently, the Working Group “Real time control” of the German Association for Water, Wastewater and Waste (DWA, formerly: ATVDVWK) has prepared a guideline document on planning of real time control (RTC) systems for urban drainage catchments. At present,
the document is in its consultation phase, its publication as a DWA guideline document is envisaged (in German language) in 2005.
This paper summarises its main issues, in order to make the guidelines available to an international audience. The guidelines will
assist the consultant engineers, wastewater system operators and authorities in estimating the RTC potential for their system and in
planning and developing RTC systems in a structured way.
Pollutant removal efficiency of alternative filtration media in stormwater treatment. N. Seelsaen*; R. McLaughlan; S. Moore; J.E.
Ball+; R. M. Stuetz
Sorption experiments were used to assess the ability of various materials (sand, compost, packing wood, ash, zeolite, recycled glass
and Enviro-media) to remove heavy metal contaminants typically found in stormwater. Compost was found to have the best
physicochemical properties for sorption of metal ions (Cu, Zn and Pb) compared to sand, packing wood, ash, zeolite and Enviromedia. The compost sorption of these metal ions conformed to the linear form of the Langmuir adsorption equation with the
Langmuir constants (qm) for Zn(II) being 11.2 mg/g at pH 5. However, compost was also found to leach a high concentration of
dissolved organic carbon (DOC, 4.31 mg/g), compared to the other tested materials. Various combinations of sand, compost and
other materials were observed to have excellent heavy metal removal (75-96% of Zn and 90-93% of Cu), with minimal DOC leaching
(0.0013-2.43 mg/g). The sorption efficiency of the different Enviro-media mixes showed that a combination of traditional (sand) and
alternative materials can be used as an effective medium for the treatment of dissolved metal contaminants commonly found in
stormwater. The application of using recycled organic materials and other waste materials (such as recycled glass) also provides
added value to the products life cycle.
Development of climate and urban drainage scenarios for impact assessment for Helsingborg, southern Sweden. A. SemadeniDavies*+; C. Hernebring; G. Svensson; L. G. Gustafsson
Presented by Annette Semadeni-Davies, Lund University, Sweden
Climate change due to human activities has the possibility of changing both the natural and built environment over the coming
decades. As the global population grows and becomes more urbanised, stakeholders have an urgent need for tools to assess the
impacts of global warming on urban water resources. However, to date, coping strategies and new technologies have not been
addressed within most hydrological impact assessments. This paper presents a project to investigate the relative effects of climate
change and changes in water management on waste-water and storm-water in central Helsingborg, southern Sweden, through
sensitivity analyses with a urban drainage model (MOUSE) and a substance transport model (SEWSYS). Scenarios are developed for
changes in both regional climate and urban draiange. The latter are based on current trends in Sweden and range from no change to
complete rehabilitation of existing pipes and use of local storm-water volume and quality controls in new housing areas. Climate
scenarios are derived from the RCAO regional climate model developed by the Rossby Centre. At the time of writing, the project was
in the modelling phase, it is hoped that initial results can be presented at this conference.
Winter water quality profiles for a stormwater pond in southern Sweden. A. Semadeni-Davies*+
Presented by Annette Semadeni-Davies, Lund University, Sweden
Profiles of conductivity, temperature, dissolved oxygen (DO) and pH were made for Bäckaslöv stormwater pond (ca. 1.8 ha, average
depth 1.6 m) in Växjö, south Sweden, over two winters (2001-2 and 2002-3). The first winter had mild and wet conditions while the
second was cold and dry. The pond was at least partially ice covered over both winters. Readings were taken at 20 cm vertical
intervals approximately every fortnight from December to April at three pond locations: the inlet, the outlet and an access bridge.
Additionally, YSI probes at the inlet (pH, temperature) and outlet (pH, conductivity, DO and temperature) were installed during the
second winter for continuous monitoring. The profiles provide an insight into the functioning of the pond, particularly following
applications of de-icing salts for traffic safety. Conductivity in particular can be used as an affordable diagnostic tool for pond
processes. It was found that chloride from de-icing salts leads to strong stratification which changes pond hydraulics. There are three
flow possibilities for flow which relate to the relative chemical characteristics of both pond and stormwater: ice dominated (fresh
pond and stormwater) ; salt dominated (fresh pond, salt stormwater); and ice and salt combined (salt pond, fresh stormwater).
55
Modelling tidal effects in catchments with large variable tidal infiltration. A. Sharpe; I.T. Clifforde+; P. Martin*
Presented by Ian Clifforde, Black & Veatch Consulting, United Kingdom (Great Britain)
This paper describes a project to find a cost effective way of reducing storm overflow spill frequency to an acceptable level on a
combined sewer system experiencing excessive tidal infiltration. Tidal infiltration reduction works had already been carried out, but
infiltration remained high. Normally, where variable tidal infiltration is present but does not comprise a significant fraction of the
flow in the sewer, an allowance can be made assuming a constant inflow equal to the peak observed tidal inflow. In this particular
study, however, the tidal component was so large that this approach would be excessively conservative. Although large rainfall
events and high tide conditions can coincide, they don’t always. A sewer network model utilising continuous simulation was used to
fully understand the impact of this tidal infiltration and then to size appropriate spill reduction measures. The paper describes how
extensive tidal inflow surveys were used to develop a synthetic long term tidal inflow hydrograph taking into account variations in
tide height throughout each month. This was used in conjunction with a long term rainfall time series to assess present and proposed
systems spill frequencies, enabling a credible assessment of proposed storm storage provision to meet the spill frequency
requirements.
Integration of low impact design into a regional stormwater programme, Auckland, New Zealand. E. Shaver*+; S. Ira
Presented by Earl Shaver, Auckland Regional Council, New Zealand
Stormwater management has been implemented in the Auckland Region for approximately 25 years. Implementation has evolved
over that time period from a water quantity programme whose focus has been to reduce flood potential, to water quality
consideration whose goals are to reduce downstream contamination. More recently, a major shift in programme focus has been to
consider streams as important aquatic resources that must be protected to the extent possible. Approximately 90% of Auckland
streams are either first or second order streams and these streams are very susceptible to adverse effects from stormwater runoff.
These effects relate to water quality issues and also to impacts related to physical structure of the channels which is related to
water quantity. The implementation of “conventional” stormwater management is based on mitigation of adverse effects to the
extent possible but those practices only reduce the level of degradation rather than preventing the effects from occurring in the first
place. Since protection of streams is now a programme priority, a revised approach to stormwater management has become
necessary. The paper explores how Auckland’s stormwater programme is integrally linked to the implementation of low impact
design principles. It discusses the main elements of the programme (i.e. integrated catchment management planning, capabilities,
stormwater solutions, funding and education), and highlights how low impact design has been incorporated into each workstream.
Case studies on both a site and watershed basis are also presented.
Estimation of solids loadings to rainfall-runoff unit operations using a unit pollutograph concept for source area watersheds. Y.
Sheng; J. Sansalone*+; F. Calomino
Source area watershed in the built environment deliver significant loads of solids and constituents such as metals, organics and
phosphorus associated with solids. The ability to model the mass delivery process of solids in small urban watersheds is essential for
advancement of rainfall-runoff quantity and quality control design in the built environment. In this study the hydrologic concepts of
the unit hydrograph (UH) and instantaneous unit hydrograph (IUH) were used to support the concepts of a unit pollutograph (UP) and
an instantaneous unit pollutograph (IUP). These latter two concepts were developed as analogous concepts for estimation of solids
mass transport loading as a pollutograph from source area watersheds. Relationships between solids mass and hydrologic volume
were based on relationships that expressed either a first-order or zero-order relationship between solids mass and volumetric
transport. The resulting concepts were applied to historical rainfall-runoff events where the hydrologic and water quality
measurements had been conducted. From this development a site mean IUH and IUP determined from the rainfall-runoff record and
water quality data, the corresponding site mean UH and UP were developed for solids. The hydrographs and solid pollutographs
generated by convolution of the UH and UP compared well with measurements, indicating the feasibility of the concept.
Investigation of blockage relationships and the cost implications for sewerage network management. W. Shepherd*+; A.
Cashman; S. Djordjevic; D. Dorini; A. Saul; D. Savic; L. Lewis
Presented by Will Shepherd, Pennine Water Group, University of Sheffield, United Kingdom (Great Britain)
Blockage of sewers is a problem that not only results in significant expense to water companies, but is also responsible for 45 % of
sewer flooding in the UK (NAO, 2004). An investigation into the relationships between blockage incidents and the characteristics of
the sewerage network is being carried out as part of the UK research project ‘Cost-S – A Whole Life Costing Approach to Sewerage’
funded by the Engineering and Physical Sciences Research Council (EPSRC) and the water industry. The aim of this research is to
produce a tool which will allow sewerage managers to optimise the performance of the network based on set constraints and key
performance indicators. Analysis using historic incident data and sewer asset data has resulted in useful relationships between
physical characteristics of the sewer network and blockage rates, this information will be formed into a multi-parameter model. The
model will however be limited due to the quality of data currently available – UK water companies inherited poor asset databases on
privatisation and data recorded on incidents has been limited. The companies knowledge of the underground assets is however
improving and incident recording is becoming more rigorous, thus the models could be enhanced in the future.
Development of a decision support system for integrated water resources management in intensively used small watersheds. H.
Sieker*+; S. Bandermann; K. Schröter; M. Ostrowski; A. Leichtfuss; W. Schmidt; E. Thiel; C. Peters; R. Mühleck
Presented by Heiko Sieker, Ingenieurgesellschaft Prof. Sieker mbH, Germany
The main objective of the research project WSM300 is the development of a methodology which guides and supports an improved
water resources management on the level of small watersheds (up to 300 km²). The developed methodology is to be implemented
into a software based tool within the framework of a generic Decision Support System (DSS). Core of the DSS is a “decision matrix”,
which has been implemented as a web based application (www.wsm300.de). The management objectives are represented by the
indicators labelling the rows. They will be the result of a discussion of the objectives and problems in the specific sub-basin, which is
supported by the catalogue of indicators. The matrix, once the labels are defined, serves as a plot for the planning process, defining
clearly which objectives have to be considered and which indicator-values have to be calculated. The DSS further includes a concept
and tools for the combination of existing software components and supports the processing of model-outputs to indicator-values.
Filled with the indicator-values, the matrix allows a comparison of the scenarios and provides a good basis for a decision. If desired,
multi-criteria decision aid methods can further help find the optimal scenario and mediate between stakeholders. As a co-product of
the web-based DSS, the “River-Information-System” was established informing the public about the newest developments in their
catchment.
Developing a planning and design framwework for retrofit SUDS. R. Singh*+; C. Jefferies; V. Stovin; G. Morrison; S. Gillon
Presented by Rohit Singh, University of Abertay Dundee, United Kingdom (Great Britain)
Sustainable Urban Drainage Systems (SUDS) are attracting increased attention due to their ability to attenuate flow, reduce flooding
and improve water quality. However, planning of retrofit and new SUDS remains unclear in the context of pollution control, hydraulic
efficiency and urban planning. Recent research has produced an initial methodology for the design and planning of retrofit SUDS in
combined sewer areas. The methodology was applied in this new study initially to construct a database of all retrofit options such as
roofs, car parks according to their land use. A second inventory was created for open spaces, classified according to their functions:
vacant and derelict land; parklands; private property; and play areas. A conceptual disconnection of urban surfaces was analysed for
two trial locations using a hydraulic model for the drainage area and the studies indicated the need for catchment scale
disconnections. It was found that different priorities result where an improvement in water quality in the streams is preferred over
options which only address hydraulic deficiencies. A framework for prioritisation of retrofit SUDS based on water quality
improvement was developed addressing the type of drainage system, the land use, the type of retrofit option, and the available
open space.
Laboratory experiments for predicting clogging in stormwater infiltration systems. N.R. Siriwardene*; B. E. Hatt; A. Deletic+; T.
D. Fletcher
Presented by Ana Deletic, ISWR, Australia
Infiltration systems divert urban stormwater away from the surface runoff path, acting to temporarily store and then infiltrate it into
the surrounding soils. However, these systems have a very high failure rate due to clogging. Research is being conducted at Monash
University to develop a fundamental understanding of clogging processes and to develop a new clogging prediction method for
stormwater infiltration systems. This paper presents the method and results of the preliminary experiments carried out on a one
dimensional rig. The experiments were conducted in order to investigate transport of sediment particles in stormwater through the
filter media and soil underneath it, by simulating vertical flow through typical infiltration systems. Both constant and fluctuating
stormwater levels in the system were studied to examine the effect on the clogging process. It was found that a clogging layer will
form on the interface between the filter medium and soil. If the water level in the system is held constant, a large percentage of the
sediment concentrates around that water level. This has important implications on modeling of clogging in systems that do not
empty completely.
Determination of CSO spill frequency based on rainfall data. M. Skotnicki; M. Sowinski*+
Presented by Marek Sowinski, Poznan University of Technology, Poland
In the paper a simple method of CSO spill frequency determination, which uses historical rainfall records and linear reservoir model,
was described. The method is based on evaluation of characteristic parameters, such as the time of duration and the intensity of the
rainfall which initiates CSO, further referred to as the initiating rainfall. A constant rainfall intensity and a runoff formation only
from impervious surfaces was assumed, neglecting runoff hydrograph transformation in sewers by derivation of basic relations of
presented method. An initiating rainfall is determined individually for particular CSO as a function of the catchment parameters and
the parameters of CSO spillway. The initiating rainfall intensity is calculated on basis the flow with depth equal to weir crest level.
The duration time of initiating rainfall is a function of catchment parameters and travel time in sewers. Classification of historical
rainfalls according to parameters of initiating rainfall makes possible to determine the number of rainfalls generating CSO spills in a
specified period, hence the frequency of spills can be easily computed. In the paper a case study results were presented. Results
obtained from described method are almost the same as results of SWMM5 package simulation of the rainfall-runoff process in urban
catchment.
Integrated urban catchment modelling for a sewer-treatment-river system. A. Solvi*+; L. Benedetti; L.; Weidenhaupt; A.;
Vanrolleghem; P.A.
Presented by Anne-Marie Solvi, CRP Henri Tudor, Luxembourg
River water quality can be improved by optimising the urban wastewater system management through integrated operation of the
transport and the treatment of these waters. Mathematical models are then useful tools to understand and explore the system in
question. They allow to test various operating strategies and to see their effects on the long term. In this study of a river catchment
in Luxembourg, the WEST® software is used as the modelling and simulation platform for the whole integrated system. It already
contains standard models for WWTP and river processes. For surface runoff and sewer transport, the KOSIM hydrological model was
implemented into the WEST® model-base. The implementation was thoroughly verified by comparing simulation results from both
softwares. Also, backwater effects are taken into account through a conceptual model of backflows and results are compared to
hydrodynamic results obtained with the InfoworksTM CS software. These are then used to calibrate the former.
Reduction of pollution load from street-runoff by an inlet-filtration-system filled with adsorptive material. H. Sommer*+; H.
Sieker
Presented by Harald Sommer, Ingenieurgesellschaft Prof. Dr. Sieker mbH, Germany
Pollution of surface waters by runoff from sealed areas is coming more into focus. As shown by several national and international
studies, this part of wastewater cannot be neglegted. There are different strategies to reduce emission from urban runoff. One is to
reduce the pollution load to rivers and lakes by centralised retention, purification tanks and centralised constructed wetlands. An
alternative strategy is source control. The presented solution in this paper concerns the thousands of inlets in urban areas draining
highly polluted runoff from roads and highways. This solution consists of a cartridge that can be inserted into standard inlets. Within
2 filtration steps, a settling volume and a adsorptive filtration, the inflowing runoff is treated. The results of the quality
measurements are: - a mixture of special filter sand with an adsorptive material is suitable for different inorganic and organic
compounds. - a high retention for suspended solids was found - a significant reduction for heavy metals (zinc and copper), ophosphate, and PAC was observed.
The development of geotextiles incorporating slow release phosphate beads for the maintenance of oil degrading bacteria in
permeable pavements. G. E. Spicer*+; D. E. Lynch; A. P. Newman; S. J. Coupe;
Presented by Gillian Spicer, Coventry university, United Kingdom (Great Britain)
The development of a self-fertilising geotextile mat designed to provide a sustained slow-release of required inorganic nutrients for
the growth of oil degrading micro-organisms in porous pavement systems (PPS) is reported. The system comprises a geotextile spun
from polymer fibres containing spherical phosphated polymer beads that release phosphate upon contact with water at a desirable
level for microbial growth. Initial results using model PPS have shown that the self-fertilising geotextile system works very
effectively as increased microbial activity has been observed throughout the experiment, illustrating that the oil-degrading bacteria
can effectively utilize this polymer composite as a suitable nutrient source.
Water quality performance of SUDS ponds analysed on a WQI. A. Spitzer*+; C. Jefferies
Presented by Adolf Spitzer, University of Abertay Dundee, United Kingdom (Great Britain)
Results from a three year water quality (WQ) monitoring in two SUDS ponds are presented and the use of a water quality index (WQI)
as a method for determining the WQ performance of Sustainable Urban Drainage Systems (SUDS) is proposed. WQ data were
collected at the inlets and outlets of the Halbeath and Linburn ponds, located in adjacent catchments in the Dunfermline Eastern
Expansion Area (DEX) in Eastern Scotland. Pond inflows and outflows were analysed for DO, pH, TSS, turbidity, chloride,
conductivity, NH3 and O-P. The results show that both ponds performed well in removing TSS. There was no evidence of nutrient
removal in either pond. Runoff from the residential housing area in the Linburn pond catchment typically carried the highest
pollutant loads and the data suggest that several pollution events occurred during construction in the catchment. Improvement of
57
site practices and better housekeeping in residential areas would lead to significant runoff improvements. The use of a parameterweighted WQI for WQ analysis is proposed, as it can be easily adapted to SUDS situations. A WQI also allows better evaluation of
SUDS performance than evaluation from single WQ parameters and is suitable for use in modelling software and standard spreadsheet
applications.
Dynamic modeling of detention tanks for flood control in urban drainage systems in developing countries. P. Sreeja*; K. Gupta+;
O. Mark
Presented by Kapil Gupta, Indian Institute of Technology Bombay, India
Increasing urbanization and high population density have resulted in an increase in the impervious areas in the cities. This results in
flooding and overloading of existing drainage systems. Implementing structural measures for controlling urban flooding are extremely
difficult due to the space constraints in densely populated cities in developing countries. An alternative cost effective solution can
be achieved by implementing a control strategy for the existing control structures at different locations in the drainage network. In
this direction, a detention tank in the drainage system can be effectively used for storing excess water during high intensity rainfall
and subsequently releasing it to the downstream drainage channel using a flow control mechanism, to optimize the capacity of the
drainage system. With this in view, an effort has been made to develop a dynamic numerical model, which incorporates the
influence of controller units for the operation of gates of detention tank in order to control the flow. The response characteristics of
the system in time and frequency domain have been discussed in this paper. The validity of the developed model has been
demonstrated by simulating it for a catchment near Mumbai, India. The results were analyzed to emphasis its importance in field
application.
Sewer invert trap design using laboratory and CFD models and continuous simulation. V.R. Stovin*+; A.N.A. Schellart; S. Tait;
R.M. Ashley; R. Burkhard
Presented by Virginia Stovin, The University of Sheffield, United Kingdom (Great Britain)
The focus of the research reported here was the need to provide a robust design for a new sewer invert trap within a comparatively
short timescale. In order to achieve this goal the authors have brought together three complementary engineering tools:
Computational Fluid Dynamics (CFD) modelling; laboratory modelling and continuous hydraulic simulation. The paper will describe
the basis behind the use of each of the tools and demonstrate how their results were integrated – within a short timescale – into the
design and construction process. In all three components of the study sediment behaviour was characterised according to grain size
distribution. Construction of the invert trap is underway, and a comprehensive programme of flow and sediment accumulation
monitoring is planned.
Reliability and safety of sewer system. D. Stransky*+; P. Fatka
Presented by David Stransky, Czech Technical University in Prague, Czech Republic
Knowledge of the hydraulic reliability and safety of the gravity sewer system is important for nearly all actors of urban drainage. The
main goal of the presented project was to develop a methodology enabling flexible, simple, complex and transparent assessment of
hydraulic behaviour of the sewer system. The methodology allows to perform an assessment related to different functional regimes
(e.g. pressure flow, surface flooding) as well as to different spatial (manhole-sewer system) and temporal scales (rain event–long
term period). The procedure developed was tested in an experimental catchment in Prague. Application of the methodology on
existing sewer systems is preferred. Its use for the sewer system design is possible but results should be interpreted with respect to
the design uncertainties (especially in the runoff coefficient). Until the design uncertainties are reduced to an acceptable level, the
effective use of reliability and safety as design criteria will not be feasible.
Development of the San Diego creek natural treatment system. E. Strecker*+; P. Mangarella; N. Brandt; T. Hesse; K. Rathfelder;
M. Leisenring
Presented by Eric Strecker, GeoSyntec Consultants, United States of America
A Natural Treatment System (NTS) Master Plan that includes a watershed-wide network of constructed wetlands was evaluated for
treatment effectiveness of dry weather base flows and runoff from smaller more frequent storms in a 120 square mile (311 km2)
urban watershed. The goal of the ‘regional retrofit’ wetland network is to serve as an integral component in watershed-wide Best
management Practices (BMPs) for compliance with pollutant loading limits (TMDLs) requiring discharge limits of sediments, nutrients,
pathogen indicators, pesticides, toxic organics, heavy metals, and selenium. The NTS Plan was assessed with ‘planning-level’ water
quality models that account for the integrated effects of the planned 31 NTS facilities. The NTS Plan is estimated to achieve total
nitrogen (TN) TMDL for base flows and reduce in-stream TN concentrations below current standards at most locations. Total
phosphorous TMDL targets would be met in all but the wettest years. The fecal coliform TMDL would be met during the dry season,
but not all wet season base flow conditions, and not under storm conditions. The NTS Plan is not designed to meet the sediment
TMDL, but would capture, on average, about 800tons/yr (726,000 kg/yr) of sediment from urban areas. The wetlands are estimated
to remove 13 percent of the total copper and lead, and 12 percent of the total zinc in storm runoff.The NTS Plan provides a costeffective alternative to routing dry-weather flows to the sanitary system.
Storm water management in the town of Unicov. Idea – Design – Construction – Operation - Evaluation. M. Suchanek*+; R. Kuby;
J. Kozusnicek; J. Vychodil
Presented by Milan Suchanek, DHI Hydroinform a.s., Czech Republic
The paper introduces a design and an evaluation of a function of a storm water retention system (retention tank and in line storage)
at the Unicov sewer network. The system design was based on the MOUSE mathematical model in 2001. The structures were
constructed based on this design during the period of 2002 – 2003. It was possible to make first evaluations of the system
performance in 2004, having one year of the operation experience.
Distributed hydrologic model with Bayesian Monte Carlo technique to estimate surface loading in urban area. D. Sutani*+; T.
Kawaguchi; M. Shirahama
Presented by Sutani Daisuke, Nihon Suidou Consultant Co.,Ltd, Japan
There are a lot of uncertain factors involved in runoff analysis for urban area. Among others, accumulated non-point loadings on
urban surface and in ditch or drains are eminent parameters, which are generally introduced as definite values into runoff model.
However, it is desirable that these parameters are treated as continuous probability variables so as to discuss and make decision for
effective counter measures based on the degree-of-belief of the model parameters. In order to obtain probability density function
(PDF) of the parameters, distributed hydrologic model with Bayesian Monte Carlo (BMC) technique is applicable. BMC technique is a
combination method of Bayes’ inference and Monte Carlo technique. Although BMC technique has a significant benefit of the ability
to reduce total model output uncertainty, it includes limitations of computational requirement. Especially, when it is necessary to
treat a lot of parameters like distributed hydrologic model, the application of BMC becomes difficult. In this paper, new methodology
for handling BMC procedure to remain the above benefit and to overcome its disadvantage is developed and proposed. And
application results of distributed hydrologic model with BMC technique are presented.
Performance of a High-Rate Sedimentation Process for Combined Sewerage Treatment in Wet Weather. K. Suzuki; T. Fujihashi;
S. Kosanda*+; H. Hinuma; R. Hata
Presented by Sakae Kosanda, EBARA Corporation, Japan
A novel high-rate sedimentation process has been developed for directly treating combined sewer overflows (CSOs). This was done
using a test facility at an actual wastewater treatment plant in Tokyo. Pilot test results, carried out 13 times, from December 2002
to July 2003 in wet weather, suggested that the process was suitable for treatment of CSOs. The performance of the process was
favorable at 50 m3/(m2 ·h) up to 880 mg/L influent TSS, removing between 78 % and 91 % of TSS at loading and between 64 % and 85
% of BOD5 also at loading. The pilot testing clarified that a decrease in the influent alkalinity due to rain water caused a drop in the
pH after FeCl3 addition and thus improved coagulation, with a significant decrease in the effluent TSS. Mixing, coagulation and
flocculation were carried out in a baffling type mixing tank to enable uniform mixing without any short-passes. Coagulation
conditions in this mixing method were evaluated and results clarified that rapid mixing was required momentarily after each addition
of FeCl3 and polymer, i.e. to diffuse these additives into the influent.
Computer Aided REhabilition of Sewer and Storm Water Networks (CARE-S). S. Sægrov*; W. Schilling; R. Ugarelli+
Presented by Rita Maria Ugarelli, Bologna University, Italy
Sewer and storm water systems in cities worldwide suffer from insufficient capacity, construction failures and pipe deterioration.
The consequences are structural damage and local floods leading to inflow of water into basements, traffic disturbances, street and
surface erosion, and pollution of local receiving waters. CARE-S is a computer based system developed to meet this challenge. It is
designed for sewer and storm water network rehabilitation planning. It provides fundamental instruments for estimating the current
and future condition of sewer networks, i.e. performance indicators, selecting and ranking of rehabilitation projects and long-term
investment needs. The procedure for selection and ranking of projects is supported by tools for analysis of structural failures and
hydraulic performance. Socio-economic issues are also included in the priority ranking process of CARE-S.
Computer Aided Rehabilitation of Water Networks (CARE-W). S. Sægrov+; W. Schilling*
Presented by Sveinung Sægrov, SINTEF, Norway
CARE-W is a computer based system for water network rehabilitation planning. It provides fundamental instruments for estimating
the current and future condition of water networks, i.e. performance indicators, selecting and ranking of rehabilitation projects and
long-term investment needs. The procedure for selection and ranking of projects is supported by tools for prediction of network
failures and calculation of water supply reliability. The research project CARE-W was finished in 2004 and is now available for
practical use.
Historical overview of the Copenhagen sewerage system. S. Sørensen*; B. Petersen; N. Kofod; P. Jakobsen+
Presented by Per Jacobsen, Copenhagen Energy, Denmark
The Copenhagen sewerage system was established in 1857. Thus, in 2007 we celebrate our 150th anniversary. Previous to the
establishment there were some years of discussion of the principle – combined vs. separate sewer network. Most of the sewer
network we know today was founded 1860-1910. Until 1892 the contents of latrines were still collected and driven to the country for
fertilization. The rest of the sewage was lead to the harbour, causing extreme odours and sedimentation of sludge. In the time the
water closets were allowed to lead the wastewater to the sewer network, the sewage was collected in new pipes along the harbours,
and only during rain there were spills from CSO. In the harbour, public baths were established, but because of the poorer and poorer
water quality, the last bath closed in 1952. In the 1990s, a SCADA system was established and real time control introduced. Since
then, RTC is an integrated part of managing the sewer network. In the same period, some mayor projects started with the aim of
reducing the CSOs and large storage volumes were established. This resulted in the establishment of a public bath in 2002 followed
by yet another in 2003.
Alarm system for bathing water in the harbour of Copenhagen. S. Sørensen*+; N. Kofod Andersen
Presented by Sonia Sørensen, Københavns Energi, Denmark
Many projects have been made to reduce CSO to the harbour areas of Copenhagen but – according with the time schedule of the
master planning – not all the receiving areas have the required bacteriological standards as to admit bathing guests. The public
interest is intense, and an effort was made to establish the first public bathing facility in 2002. In 2003, the second facility opened.
The spots were picked in areas with CSO-structures with low overflow frequency – approx. 1-3 per year. Because of the insecurities
of the water quality, the Environmental Protection Agency (EPA) of Copenhagen, Copenhagen Energy, Sewerage Department (KE) and
Danish Hydraulic Institute (DHI) have established an alarm system. The EPA has the authority and the coordinating role and is
responsible for the informations. KE has the SCADA system and thereby the information of overflows from the sewer system. DHI
receives the SCADA information continuously and makes prognoses with the MIKE-model of all the harbour areas. If an overflow is
registered in the SCADA system, a red flag is raised in the public bath and bathing is then forbidden. The EPA has the final decision
to hoist the green flag and controls estimations when bathing is allowed.
U.S. EPA research on urban stormwater pollution control. A. N. Tafuri*+; R. Field
Presented by Anthony Tafuri, US Environmental Protection Agency, United States of America
The U.S. EPA’s Urban Watershed Management Branch is responsible for developing and demonstrating technologies and methods
required to manage the risk to public health, property and the environment from wet weather flows (WWF) in urban watersheds. The
activities are primarily aimed at restoring surface waters in the context of water quality uses intended for aquatic life and
recreation. WWFs include combined sewer overflow (CSO), sanitary sewer overflow (SSO) and urban storm water. The primary goals
of the research are development of: (1) watershed management strategies and associated models integrating area-wide WWF control
for groundwater and surface water protection; (2) multi-purpose WWF methods, practices, and technologies including new and
retrofit designs for drainage, flood, pollution, erosion and sedimentation control, for management of contaminated sediments in
sewers; (3) pretreatment requirements for adequate WWF disinfection; and, (4) protocols for measuring WWF control program
effectiveness. The overall direction of the program is geared to developing novel approaches for controlling WWFs and the
integration of watershed based urban wet weather controls in mixed land-use watersheds for resolving water quality impairments as
well as integration with drinking water source water protection. This paper addresses select projects and products related to these
activities, especially the ongoing research activities related to best management control technologies for urban stormwater
generated pollution control.
Potentials of stored Rainwater as an alternative water resource to meet the increasing water demand: A case study. T.
Tamama*+; T. Kawasaki; Y.Nakayama
Presented by Toshihiko Tamama, Nippon Jogesuido Sekkei, Japan
Detention/storage of rainwater instead of its quick removal is an effective control measure for urban drainage. As well as its peakcut effect, multi-purpose use of stored rainwater is expected as an on-site water resource. Though Japan is not an arid area (annual
average precipitation is 1,718mm/year) serious water supply shortage arises at times in some urban areas, due to the heavily
concentrated population or industrial activities and the relatively small catchment area. Utilization of stored rainwater is thus
promoted in such areas, including Naha city, capital of Okinawa Island, located in south-east end of Japan. A feasibility study was
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conducted at Naha New Town, extending 2 km2 which was planned to be developed near the center of Naha city, aiming at
estimating the potentials of stored rainwater to substitute for the water supply system to meet the water demand. Based on day by
day mass-balance calculation and cost-benefit analysis, it is concluded that usage of stored rainwater shall be limited to domestic
use and 8.5% of water demand shall be substituted and total run-off discharge of stormwater from Naha new town shall be reduced
by 67 % through storage and utilization.
Combination of e-learning tools and face to face for urban hydrology teaching. B. Tassin*+; J. C. Deutsch
The development of new information technologies gives the opportunity to move from classical face-to-face teaching to other
learning techniques and media, including for instance Problem Based Learning, voice recording and video presentations. At the Ecole
Nationale des Ponts et Chaussées, an Internet based course was developed 6 years ago, and on the basis of successful assessments by
the students, it was decided to move to a CD-Rom course, based on recent technological tools. This CD-Rom is now under
development and it implied a full reordering of the topics of the course.
Thermal stratification in retention ponds. B. Tassin*+; B. Vinçon-Leite; A. Groleau; C. Quiblier
Retention ponds are widely used for runoff control. In France, they are particularly numerous in recent urbanised areas. They are
characterised by an area around 1ha and a depth ranging from two to four or five meters. The temperature vertical structure of two
such ponds, located in the Paris suburb, was monitored continuously over a 1 month and a10 month period in 2004. This paper aims
at showing the polymictic behaviour of these systems during Spring and early Summer. Not only a diurnal stratification is
observation, with gradient values over 10°C/m, but also stratified episodes over several days (up to 10 days) occur several times per
month. Consequence of this polymictic character on water quality is assessed on dissolved oxygen profiles.
‘Triple-bottom-line’ assessment of urban stormwater projects. A.C. Taylor*+; T.D. Fletcher
Presented by Andre Taylor, CRC for Catchment Hydrology, Australia
New guidelines have been developed and trialled in Australia to assist urban stormwater managers to assess options for projects that
aim to improve urban waterway health. These guidelines help users to examine the financial, ecological and social dimensions of
projects (i.e. the so-called ‘triple-bottom-line’). Features of the assessment process described in the guidelines include use of multi
criteria analysis, input from technical experts as well as non-technical stakeholders, and provision of three alternative levels of
assessment to suit stormwater managers with differing needs and resources. This paper firstly provides a background to the new
guidelines and triple-bottom-line assessment. The assessment methodology promoted in the new guidelines is then briefly
summarised. This methodology is compared and contrasted with European guidelines from the ‘SWARD’ project that have been
primarily developed for assessing the relative sustainability of options involving urban water supply and sewerage assets. Finally, the
paper discusses how assessment methodologies that evaluate the financial, ecological and social dimensions of projects can, under
some circumstances, be used to evaluate the relative progress of options for urban water management on a journey towards the
widely pursued, but vaguely defined goal of ‘sustainable development’.
The perception of flood risk and water nuisance. T. Terpstra*+; J. M. Gutteling; G.D. Geldof; B. Kappe
Presented by Teun Terpstra, University of Twente, Netherlands
In this paper we applied the psychometric paradigm to validate a questionnaire that assesses the risk perception characteristics of
flooding and water nuisance. The state-trait anxiety inventory was used as a bench mark to determine whether perceptions are
related to anxiety characteristics. A focus group was used to further validate the questionnaire. Factor analyses of 49 questionnaires
identified eight flooding factors (explained variance: 74%) and three water nuisance factors (explained variance: 62%). Internal
consistencies of the obtained scales were moderate to high. Like in the perception of external safety risks, ‘dread’ seems to be the
most important concept binding different characteristics. Although dread towards both flooding and water nuisance is rather low, it
seems more present in the latter case. Furthermore, the extent of dread for water nuisance seems related to someone’s state
anxiety. In both cases awareness of ‘increasing risks’ is clearly present, and we find the characteristics ‘(no) dread’,
‘(un)controllable situation’ and ‘does not affect me’ to be related.
Developing the DayWater adaptive decision support system for urban stormwater source control: A challenge!. D. R.
Thevenot*+; M. Förster
Presented by Daniel Thevenot, University Paris XII & ENPC, France
Although urban stormwater management (USWM) is essential for controlling both flooding and pollution problems, decision-making in
any USWM project is especially complex since it involves a large number of stakeholders and large variety of domains of knowledge,
i.e. both technical (hydraulic, chemical or eco-toxicological) and managerial (planning, assessing, decision-making, etc…). In order
to facilitate the sustainable management of urban water management, an Adaptive Decision Support System (ADSS) for stormwater
source control will be developed by a consortium of seven European research institutions and three private companies. The resulting
3-year research project (DayWater) started in December 2002 with financial support from the European Commission (5th Framework
Programme). The major challenges of the DayWater project are presented and discussed in relation with the following points: crossdisciplinary partners, coverage of the European scale, strong end-user involvement, consideration of decision-making procedure in
urban stormwater issues. This paper aims to compare the original work plan with the progress achieved to date and to analyse the
reasons for both the success and difficulties encountered by the DayWater consortium as an example of a European research project
dealing with a complex context.
Assessment of runoff contributing catchment areas in rainfall runoff modelling. S. Thorndahl*+; C. Johansen; K. Schaarup-Jensen
Presented by Søren Thorndahl, Aalborg University, Denmark
In numerical modelling of rainfall caused runoff in urban sewer systems an essential parameter is the hydrological reduction factor
which defines the percentage of the impervious area contributing to the surface flow towards the sewer. As the hydrological
processes during a rainfall are difficult to determine with significant precision the hydrological reduction factor is implemented to
account all hydrological losses except the initial loss. This paper presents an inconsistency between calculations of the hydrological
reduction factor, based on measurements of rainfall and runoff, and till now recommended literary values for residential areas. It is
proven by comparing rainfall-runoff measurements from four different residential catchments that the literary values of the
hydrological reduction factor are over-estimated for this type of catchments. In addition, different catchment descriptions are
presented in order to investigate how the hydrological reduction factor depends on the level of detail regarding the catchment
description. When applying a total survey of the catchment area, including all possible impervious surfaces, a hydrological reduction
factor of approximately 0.5 for residential areas with mainly detached houses is recommendable - contrary to the literary
recommended values of 0.7 - 0.9.
Urban Drainage in Cold Climate - Education and Training. S.T. Thorolfsson*+; B.V. Matheussen
Presented by Sveinn T. Thorolfsson, NTNU, Norway
The overall goal of this project is to contribute to education and training in urban drainage in cold climate. If engineers are to
handle year round urban drainage in cold climate, they must have education and training within urban drainage in cold climate
conditions. The project, Education and Training Laboratory on Urban Drainage in Cold Climate (ETL-UD-CC) was implemented at
Department of Hydraulic & Environmental Engineering, (NTNU). ETL-UD-CC is based on internet connection between Risvollan urban
hydrological field laboratory (RUHFL) and Risvollan urban hydrological station (RUHS). RUHS is designed for year round measurements
in cold climate. RUHS is made online. This make real time data and the urban hydrological database back to 1986 available in the
classroom. The students can then rub model calibration and verification in the classroom using real time and historical urban
hydrological data. The key parameters in cold climate are the snow water equivalent (SWE) and the snow covered area (SCA). The
urban snow melt modeling is still in the early stage. The field measurements and the real time data make it possible for the students
to make decisions on what to do in operating the urban drainage system and to simulate the effects on the urban drainage system
year round. The student enjoy staying outside the classroom and the feedbacks are promising The authors believe that TEL-UD-CC
may contribute to education and training in urban drainage in cold climate.
Planning for urban floods in Sweden: the situation in Kristianstad. D. Thorsteinsson*+; A. Semadeni-Davies; R. Larsson
Presented by Dadi Thorsteinsson, Lund University, Sweden
The physical planning process with respect to urban flood risk in Sweden is currently at the forefront of public perception following
several floods in urban areas over recent years. The Swedish planning process has a four-tiered hierarchy covering a range of spatial
scales from larger scale comprehensive plans to individual building permits; generally, the smaller the area, the tighter the planning
required to manage flooding. There is a judicial vacuum when it comes to who has responsibility for ensuring sound flood risk
management within the planning process. Although areas of special risk should be indicated in the comprehensive plans, these are
not legally binding. Whilst they must adhere to Swedish law, municipalities have autonomous control over land-use planning within
their borders. This fact can and does lead to unnecessary flood exposure when the flood risk expertise is either lacking in a
municipality, or available expertise is not included in the planning process at an early stage. This article focuses on the situation in
Kristianstad, southern Sweden, from the city’s foundation to present day. The city, population 75 000, and the risk of flooding is
unusually pronounced due to its low-land (partly below mean sea level) location on a flood plain.
Hydrogeological investigations at an urban area of Union Brewery, Ljubljana, Slovenia. B. Trcek*+; A. Juren
Presented by Branka Trecek, GEOLOGICAL SURVEY OF SLOVENIA, Slovenia
An urban lysimeter has been constructed within a highly urbanised and industrialised area at Union Brewery in Ljubljana (the capital
of Slovenia) with the intention of monitoring and controlling the environmental impacts of industry and traffic on Pleistocene alluvial
gravel aquifer, which is an invaluable groundwater resource of the brewery. The physico-chemical and isotopic properties of sampled
groundwater have produced general information on the hydrodynamic functioning of the study area and on solute transport – the
main flow components, the flow hierarchy and the environmental response to the flow system have been indicated. Two important
flow types were identified - lateral and vertical flow. The former has an important role in groundwater protection, while the latter is
the main influence on contaminant transport towards the aquifer saturated zone.
Potential surface pollutant load of daily rainfall for stormwater disposal planning in urbanized basin. E. Trulli*+; G. Boari
Presented by Ettore Trulli, Università degli Studi della Basilicata, Italy
The efficient planning of stormwater disposal in densely urbanized basins during rain time periods requires the verification of the
pollutant load discharged into the end receiver water body and, according to the law, should keep into account the specific use the
water resource is devoted to. It is difficult to foresee the associated polluting loads especially because of the irregular succession of
rainfall, the complex evolution of transport processes on the surface basin and the flow variability in sewers. In order to calculate
the surface polluting load rates of drainage water conveyed into separate sewerages, the present paper illustrates the results of an
elaboration regarding the daily rainfall observed in the urbanized basin of the river Basento in Potenza. The rain events we examined
were characterized by a total depth higher than10 mm. Total suspended solids and COD were examined as quality parameters. Total
mean and peak loads were calculated. A simulation of the water quality was carried out by means of EPA-SWMM. The input phase has
been implemented using a data processing system which allowed us to elaborate drainage basin territory data.
Reducing detention volumes with improved outlet structure. B. P. Tullis*+; E. C. Olsen; K. Gardner
Presented by Blake Tullis, Utah State University, United States of America
Detention basin outlet flow control structures typically include a weir, orifice, and/or culvert. One disadvantage of these types of
control structures is that the flow rate continually varies with the water level in the detention basin. The corresponding outflow
hydrographs for such control structures are typically bell shaped, with the maximum allowable peak flow duration lasting only a
“moment” at the point where the rising leg of the hydrograph transitions to the falling leg of the hydrograph. The outlet control
structure is sized according to that maximum flow rate that lasts for only a moment. The required storage volume of the detention
basin is the difference between the basin’s inflow and outflow hydrographs. This paper describes the mode of operation and presents
experimental results of a new detention basin outlet structure (DBOS) where the outflow hydrograph reaches the allowable peak
discharge early in the storm event and maintains that flow rate for the majority of the runoff period. By increasing the discharge
rate from the detention basin, the required storage volume can be reduced. This can result in significant economic savings,
particularly in areas where the available land is either very expensive, scarce, or both.
Towards a new business model in urban drainage modelling and hydroinformatics. E. Tumwesigye; Z. Vojinovic*+; A. Jonoski; M.
B. Abbott
Presented by Zoran Vojinovic, UNESCO-IHE, Delft, Netherlands
A now long-standing view of the software supply-industry is that "software is a product", whereby various software components are
combined and coordinated in conveniently packaged forms that can provide solutions to specified ranges of practical engineering
problems. The development in the use of the Internet has however more recently brought with it a new way of thinking about
modelling, whereby the software can be employed as required, or ‘on demand’. Currently, the software developers/vendors sell
their often expensive products to organisations that normally have projects from which they are able to recoup the costs of the
packages and to pay the associated maintenance fees. Once the decision has been made to purchase a particular modelling product,
the change to an alternative (which in each case again may be expensive) can be very difficult to justify. This imposes several
limitations upon the organisations involved in the provision of urban-drainage modelling service. Therefore, a more current view is
that it may in many cases be better to move away from a supply-driven to a demand-driven market model in which small packets of
software are made available to the clients via Internet facilities in such a way that the clients are easily able to assemble these
packets into software that serves their purpose for the period that it is required. This paper describes a new concept of
hydroinformatics modelling software which has evolved as a response to these new technological developments and rapidly changing
market conditions. Although this necessitates some technical innovations, it is not primarily a technical development, but it is an
essentially sociotechnical development since it involves quite substantial inter-institutional changes within the structure of
organisations providing modelling and more general hydroinformatics services. It is emphasised that this development in no way
supersedes that associated with packaged software products, but complements it. Indeed, just to the extent that this new paradigm
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is adopted, more organisations than ever can be expected to ‘graduate’ further to owning their own software products supported by
their own in-house expertise.
Synthetic flood simulation in urban area and application of simulation model. T. Uetsuka*+
Presented by Tetsuhiko Uetsuka, Environment and Sewerage Bureau,City of Osaka, Japan
To mitigate flood damage in urban areas, such preventive policy as disaster prevention program and evacuation procedures should be
effectively established together with upgrading and expansion of sewerage systems and improvement of rivers. However, it is
difficult to effectively design these measures unless the magnitude of flood is accurately estimated in advance on the basis of the
physical conditions of the targeted area and the present states of sewerage system development and river improvement. In this
paper, we describe and discuss the results of flood simulation that we performed using a synthetic flood simulation model, which
enables us to integrally analyze the behavior of water in sewer pipes, rivers, and flood plain. Furthermore, we report some examples
of examination of flood damage prevention manuals that we have drawn up on the basis of the simulation results.
Evaluation of rehabilitation impact on hydraulic and environmental performance of sewer systems (WP3 CARE-S Project). R.
Ugarelli*+; G. Freni; V. Di Federico; T. Liserra; M. Maglionico; M. Pacchioli; P. Prax; S. Sægrov; N. Schulz
Presented by Rita Maria Ugarelli, Bologna University, Italy
The research project CARE-S (Computer Aided RE-habilitation of Sewer Networks) deals with public sewer and storm water networks
of any dimension. CARE-S aims to analyse the structural and functional reliability of wastewater networks at minimum cost and
disturbance. The ultimate product will be a Decision Support System (DSS) that will enable municipal engineers to establish and
maintain effective management of their sewer networks. The project work plan follows a logical structure for the necessary work. It
is divided in 10 Work Packages (WP) and each WP is distributed among several partners. The present paper presents the structure
and the final results of WP 3 .The work package aim is the description of hydraulic and environmental performance of drainage
systems both in the present condition and in possible future scenarios considering sewer system temporal decline and the application
of feasible rehabilitation techniques.
Soil filters for enhanced treatment of CSO - Recommendations and developments in Germany. M. Uhl*+; U. Dittmer; S. Fuchs
Vertical flow sand filters have been developed as powerful tools for treatment of combined sewage overflow. Essentials of two
technical guidelines (MUNLV (2003), DWA M 178 (2005)) are described which were recently worked out in Germany with significant
contributions by the authors of this paper. The recommended layout comprises a retention basin on top of a sand filter layer (grain
size 0/2 mm). The filter velocity is controlled by a throttle in the outflow. For COD, NH4-N and SS medians of removal rates typically
range between 70-90 % can be expected under regular loading conditions. However, extreme conditions such as exceeding loads of
SS, frequent loading and long-term inundation have adverse effects on the performance of the filter plants. Recommendations for
successful long term operation were derived from various field studies.
Enhanced treatment of CSO with vertical flow sand filters. M. Uhl*+; M. Janiczek; S. Grobe; W. Merkel
Experimental studies of vertical flow sand filters for CSO treatment were conducted in lab and semi scale to investigate the
dependency of processes and treatment efficiencies on filter material characteristics and operational boundary conditions. It was
found out that sands with grain sizes of 0/2 mm and carbonate additives offer the best material conditions for high elimination rates.
Artificial throttling of the outflow to constant 0.01 l s-1m-2 proved to be essential for high treatment efficiency for ammonium, COD
and faecal bacteria. Long impoundage causes adverse effects resulting in high outflow concentrations and low treatment
efficiencies. After each feeding the filters must be emptied for regeneration which is completed within 1-2 days. Too long dry
periods impair the treatment abilities due to reduced bacteria population in the filter. Treatment efficiencies reached medians over
90 % for ammonium, medians about 70 % for soluble COD and medians about 90 % for total COD. Bacterial concentration of
hygienically relevant microorganisms can be reduced by 1-2 log steps.
Discharge control by a side weir in a triangular main channel. A. Uyumaz*+
Presented by Ali Uyumaz, Istanbul Technical University, Turkey
Side weirs have been used extensively for water-level control in irrigation and drainage canal systems, as a means of diverting excess
water into relief channels for flood protection works, and as storm overflows from urban sewage systems. A complete analytical
solution of the equations governing the flow in the side weir channels is not possible. Until quite recently, approximate methods
based on experiments conducted over a limited range of the many variables involved have been used. In many cases, the use of such
methods caused very substantial errors in the calculated spill discharge. The flow over a side weir in a rectangular channel has been
the subject of many investigations but there are no more studies about side weirs in a triangular channel reported in the literature.
In this study, numerical investigations of flow over side weirs in triangular channels are reported. Numerical models are obtained
from energy principles on the basis of a constant energy assumption and solved by a finite difference method. The results are
presented in graphical form. The study covers both sub- and supercritical flow regimes. Derived expressions are compared with
experimental results for the side weir discharge and water surface profiles for these regimes. KEYWORDS Side weir; discharge;
discharge capacity; water surface; triangular channel
Performance indicators for waste water treatment and urban drainage system. G. Vaes*+; P. Swartenbroekx; F. Provost; S. Van
den Broeck; L. Bourgoing
Presented by Guido Vaes, HydroScan, Belgium
In Flanders the practical implementation of investments in main sewers and treatment plants and the exploitation of it, is carried
out by Aquafin. The investments are commissioned by the Flemish government, who wants to introduce a result commitment that is
function of the performance of the management of the waste water transport and treatment system. To realise this, a framework of
performance indicators was worked out and tested. For the typical Flemish waste water system this framework of performance
indicators was set up with respect to the optimal management of the system (treatment plant + urban drainage system). First, a
literature study was carried out in order to find similar examples in other countries. In the second phase a basic framework of
performance indicators was set up based on the knowledge of the waste water system, the literature and the available
measurements. The focus was to use as much as possible (easily and objectively) measurable parameters for the calculation of the
performances. In a third phase this framework was tested on three pilot cases, i.e. the total drainage system to three different
treatment plants. In the final phase the methodology was further refined and finalised.
Filtering method for infiltration flow quantification. G. Vaes*+; B. Willems; J. Berlamont
Presented by Guido Vaes, HydroScan, Belgium
In Flanders, most of the drainage systems are combined sewer systems, in which waste water and rainfall runoff are drained
together. However, not only rainfall runoff enters these pipes. Also other sources of water have a contribution to the flow, as e.g.
infiltration of groundwater in the pipe system, inflows from drains, creeks, etc… These flows of relatively clean water also arrive at
the treatment plant where the influent is diluted and the treatment efficiency consequently decreases. In order to plan actions to
reduce these undesired inflows in the drainage system, it is necessary at first instance to quantify these flows. This paper describes a
filter methodology to determine the quantities of these undesired inflows from a time series of the total influent based on the
recession times of the different subflows.
Urban water management as a change process. E.A.E.M. van Beurden*; G.D. Geldof+
Interactive implementation is a method for the transition from an end-of-pipe approach to a source control approach (in this paper
by means of an urban water plan process) for the existing urban areas. But the success of interactive implementation cannot be
guaranteed. Based upon experiences in the water plans of Nijmegen and Nieuwegein, six conditions for a successful process based
upon interactive implementation, are formulated. Those conditions are usually not met at the start of the process and require a,
small, organisational change. Kotter’s theory of organisational change provides a framework for this small change process.
Climate change and urban Drainage: Strategies. H. Van Luijtelaar*; W. Stapel; M. Moens+; A. Dirzwager
Presented by Michel Moens, ARCADIS, Netherlands
The national study ‘Climatic Change and Urban Drainage: Quick Scan’, in the Netherlands has shown that climatic change can have a
significant effect on the functioning of urban drainage systems, Van Luijtelaar and Dirkzwager (2002).It is important to anticipate on
the effects of climatic change knowing the fact that urban drainage systems are realized for a period of 40 years or more. The
follow-up project called ‘strategies’ is aimed at developing ‘strategies’ to anticipate on possible effects of climatic change on the
urban drainage system. One of the project’s main considerations is to set up cost-effective strategies, which can be refined from a
general to a more specific level. The project aims to bring together the expertise of numerous specialists on the fields like: waste
water systems (sewer systems, transport of sewage water, sewage treatment plants); water systems (quality, quantity, nature,
ecology); urban environment (spatial planning, traffic and transport, urban development); society (legal and regulatory issues,
financing, economic aspects, public perception). Several sessions were organized where experts examined the functioning of urban
wastewater systems from various angles. RIZA, the Institute for Inland Water Management and Wastewater Treatment, has
commissioned Tauw Consulting Engineers in cooperation with DHV and ARCADIS, to carry out this project.
Cost-effectiveness of in-stream aeration to improve river water quality. V. Vandenberghe*+; P.A. Vanrolleghem
Presented by Veronique Vandenberghe, University Ghent, Belgium
In this research the cost-effectiveness of in-stream aeration as a measure to improve river water quality is examined. Different
processes are compared in terms of costs to be able to calculate the magnitude of the costs related to in-stream aeration. A dynamic
QUAL2E river water quality model of the Dender river, implemented in ESWAT is used to simulate one-year time series of dissolved
oxygen in the river. As the flow is very low during summer and large algae blooms occur, the oxygen concentration in the water is
often below critical levels. To avoid fish kills, an acute intervention like aeration can be necessary. However, other measures in the
urban wastewater system exist that are more profound and sustainable. Unfortunately, the costs of such measures are much higher
and in this research the aim was to evaluate the results of other measures on DO concentration and to compare those with in-stream
aeration. The measures considered are connection of still directly discharging households to the sewer system, shading and diffuse
pollution reduction. Diffuse pollution reduction seemed not to be important as long as point pollution inputs were discharging
considerable amounts of nutrients to the river. Point pollution input reduction is very successful if not only BOD but also nitrates and
phosphates are eliminated. However, the implementation takes very long. Shading is a not costly, attracting intervention that can
make other measures more cost-effective.
Statistical classification of frequent rainfall events as a basis for operational aspects of sewer systems. H.-R. Verworn*+; S.
Kraemer; L. Shi
Presented by Hans-Reinhard Verworn, University of Hannover, Germany
Statistical analysis of rainfall and runoff are generally carried out for design and rehabilitation purposes. All processes generated by
smaller events are of no interest in this context. While these design events have no relevance for the everyday performance of the
drainage systems, statistical analysis of the more frequent events has to cover more aspects than just the maxi-mum intensities of
certain durations. Operational aspects for sewer systems include e.g. sedi-mentation and remobilisation of settleable solids which
depend mainly on turbity, velocity and bed shear stress. In this investigation the whole rainfall process has been analysed for the
frequency of events with certain properties. In a first step a subdivision of the rainfall process into secluded rainfall events has been
carried out. The effects of various lengths of time with no rain between the events are described. Then the maximum intensities for
various durations are determined and analysed for their frequency resulting in frequency distributions. The re-sults are also related
to the total number of events and to design rainfall values. The applica-tion of the results for operational purposes is demonstrated
by an example. Assuming quasi-linear transformation from rainfall into runoff the findings on the rainfall side are transferred to the
runoff side leading to frequency distributions for flow and velocity.
Real-time urban runoff simulation using radar rainfall and physics-based distributed modeling for site-specific forecast. B. E.
Vieux*+; .B. Bedient; E. Mazroi
Presented by Baxter Vieux, University of Oklahoma, United States of America
Quantitative precipitation estimates (QPE) derived from radar are useful in runoff simulation in urban drainage. Simulation
experiments using radar data sampled at various resolutions identify the limits to predictability for various basin sizes. Spatial
resolution of radar rainfall used as input to a distributed model affects prediction error and scales with drainage area. Radar data
used in this analysis are derived from both S-band (NEXRAD) and X-band radars. Using radar QPE derived from the existing WSR-88D
(KHGX) as input to a physics-based hydrologic model of Brays Bayou (260 sq. km.) provides a baseline for comparison and guides
design of future radar networks. Results of experiments using historical radar events, including the tropical storm Allison, indicate
that accurate rainfall-runoff predictions in real-time are possible and useful for site-specific forecasts. Radar and distributed
hydrologic model provide accurate rainfall and runoff data supporting site-specific flood information.
HYDROPLAN-EU Knowledge Management Framework for Urban Water Asset Management. Z. Vojinovic*+; R.K. Price; W. V. den
Broek
Urban water networks for water supply, sanitation and storm drainage provide important services, the failure of which can be very
serious for the urban environment and the population. The sustainability of such assets, which frequently, if not continuously,
interact with each other and with other components of urban water cycle (i.e., surface water, groundwater and receiving waters), is
therefore an important issue for the asset managers. The services provided by these assets are at risk in three primary respects
including structural integrity, hydraulic performance and environmental impact, which indicate the need for a total life cycle
approach to managing the network assets, from planning and design, through construction and operation to replacement and
disposal. This paper describes a 5th EU Framework project, named Hydroplan-EU, which covers asset management of water supply
and drainage networks. This project is important because of the fact that there are more than 20,000 significant wastewater and
water supply networks in Europe, most of which do not have associated with them formal asset management practices. In view of
the acknowledged need for hundreds of billions of Euros in terms of capital investments in these networks throughout Europe over
63
the next 10 years, and the need for more than 20 billion Euros on asset management activities annually, the introduction and
dissemination of an internationally accepted procedure can make significant economic savings, and bring about important
improvements in the quality of life of the communities served. In this respect, the Hydroplan-EU demonstration project promotes a
particular engineering procedure for urban water asset management that is being developed and tested in five cities in European
countries.
Dynamic least-cost optimisation of wastewater systems remedial works requirements. Z. Vojinovic*+; D. Solomatine; R. K. Price
In recent years there has been increasing concern for wastewater system failure and identification of optimal set of remedial works
requirements. So far, several methodologies have been developed and applied in asset management activities by various water
companies worldwide but often with limited success. In order to fill the gap, there are several research projects that have been
undertaken in exploring various algorithms to optimise remedial works requirements but mostly for drinking water supply systems
and very limited work has been done for the wastewater assets. Some of the major deficiencies of commonly used methods can be
found in either one or more of the following aspects: inadequate representation of systems complexity, incorporation of a dynamic
model into the decision-making loop, the choice of an appropriate optimisation techniques and experience in applying that
technique. This paper is oriented towards resolving these issues and discusses a new approach for the optimisation of wastewater
systems remedial works requirements. It is proposed that the optimal problem search is performed by a global optimisation tool
(with various random search algorithms) and the system performance is simulated by the hydrodynamic pipe network model. The
work on assembling all required elements, and the development of an appropriate interface protocols between the two tools aimed
to decode the potential remedial solutions into the pipe network model and to calculate the corresponding scenario costs is
currently underway.
Alternative engineering solutions for water pollution minimization from urban drainage systems - The case of Rio de Janeiro,
Brazil. I. Volschan Jr.*+; E. P. Jordão
Presented by Isaac Volschan, Rio de Janeiro Federal University, Brazil
Tropical climate countries use separate, instead of combined sewer systems. However, legal and illegal sewage connections to the
urban drainage system result into local water resources pollution. This paper discusses the problem causes, and shows local,
alternative and original solutions that have been adopted in recent years for its minimization in Rio de Janeiro State. It presents
practical examples of engineering solutions, emphasizes their applicability, advantages and disadvantages, as a contribution for the
theme discussion in the scenario of developing countries.
Integrated approach for hydrological modelling of Cherial watershed using remote sensing and geographical informtaion system
(GIS). P. Vuppala*+; S. S. Asadi; M. A. Reddy
Presented by Padmaja Vuppala, Jawaharlal Nehru Technological University, India
Accurate, timely and reliable monitoring and assessment of land and water resources and their systematic use and exploration for
developing new ones in Cherial watershed of A.P in southern India is carried out in the present study. The research aims to evaluate
both surface and groundwater resources in the region and develop methods for its sustainable management. Innovative methods of
remote sensing and GIS are adopted as an effective tool in meeting the objective of the study. The thematic layers are derived from
Landsat- TM satellite imagery and Survey of India (SOI) topomaps and further converted to digital format using AutoCAD software.
The derived thematic maps are integrated using Arc/Info and ArcView GIS software for the generation of final action plan maps for
water and land resources development which are optimally suitable to the terrain and to the development of water resources so that
the level of production is sustained without decline over time. Since most of the surface and ground water resources are being
exhausted in the study area, new methods such as construction of artificial recharge structures for increasing the recharge of surface
water run-off to ground water aquifers have been suggested.
Characteristics of benzo(a)pyrene in highway runoff pollution. Y. Wada; T. Ozaki*+; M. Muraoka
Presented by Taira Ozaki, Kansai University, Japan
The influence on receiving water of highway runoff is considered to be serious in Japan. On the road surface, tire wear, automobile
exhaust emissions, floating in the atmosphere and so on, accumulate on the road surface and in its lateral ditches. This polluted
matter is discharged by stormwater into the receiving water. These accumulated pollution loads contain harmful materials to both
the human body and the ecosystem. In this study, the amount of accumulated pollutants and highway runoff pollutants were
investigated by the authors. In order to grasp the characteristics of benzo(a)pyrene in highway runoff pollution, we calculated the
concentration of benzo(a)pyrene using design rainfall. In order to evaluate the influence of the public water bodies by inflow of
benzo(a)pyrene, predicted no effect concentration (PNEC) was used as the indicator in this research. PNEC of benzo(a)pyrene is
0.005 µg/L. The maximum concentration of runoff water (Cmax) and total of the product of concentration and outflow time (ΣCT)
are exceeding PNEC. Cmax and ΣCT of central peak design rainfall are the highest in the design rainfalls. In the case of central peak
design rainfall, the influence on receiving water of highway runoff is the highest.
Resident evaluation of a waterside environments. Y. Wada*+; K. Michioku; N. Wada
Presented by Yasuhiko Wada, Kansai University, Japan
The advance of urbanization has brought rapid and large-scale changes to the landscape. Development has impacted the river basins
and water circulation, thereby there are causing various problems due to changes in the volume of water in rivers and water
pollution. In Japan, with the graying of society and the expansion of leisure time, people seek “ease of mind” and they are becoming
more and more interested in the natural environments close to home. In this research we investigated extensively resident
awareness of the waterside environment in City A and studied factors necessary for and important to future improvement of this
environment based on analysis of: frequency of waterside utilization; differences in the impact of the waterside environment
between those who are satisfied with the current state of the environment and those who are not; and functions people expect from
the waterside. As a result, in order to realize a desirable waterside environment, water quality should be improved and rivers should
be made cleaner, while facilities to enable residents to safely enjoy riversides should be constructed. To enhance utilization by
residents, it is important to publicize those improvement projects that are implemented to make rivers more attractive.
New directions in low impact development: Implications for urban redevelopment. N. Weinstein*+
Presented by Neil Weinstein, The Low Impact Development Center, Inc., United States of America
Low Impact Development (LID) LID offers many innovative solutions to both dry and wet weather stormwater flow management, but
this approach also presents many challenges for the development of implementation and sustainable management strategies. This
paper will highlight the research and planning strategies that the Center has found in its work on integrating planning, and
implementation of Low Impact Development into watershed planning, design, and construction through various federal and local
grants and projects. The new objectives and opportunities for the retrofit of urban areas are requiring stormwater planners and
engineers to gain a much broader understanding of the implications and opportunities of using LID in the urban environment. The
paper will focus how LID can be used to accomplish both community redevelopment and water quality objectives. The Center has
found that LID not only offers many advantages over conventional centralized water resource protection strategies, but also presents
many new opportunities for community and economic development.
Monitoring of combined sewer overflow tanks: Results of 500 years of measurement records. G. Weiss*+; H. Brombach; C. Wöhrle
Presented by Gebhard Weiss, UFT Umwelt- und Fluid-Technik GmbH, Germany
In Germany, today about 24,000 combined sewer overflow tanks (CSO tanks) are in operation. For their dimensioning and design,
German standards are available and respected. However, efficiency and performance of these costly structures are usually not
known by the operator nor by the local water authority. Thus, a trend towards monitoring the overflow activity is observed. This
paper points out the state-of-the-art in CSO overflow monitoring. Basic features of water level measurement as well as some
plausibility checks for the data are shown. Evaluation of overflow data is rather difficult. Assessment of the overflow activity versus
hydrological data, e.g. by comparison with simulation results, is costly. A much simpler way of evaluation is the ranking and rating of
measured overflow activity. On the 8ICUD 1999, already a paper on this subject was presented. Now, 6 years later, the database of
the ranking has grown to more than 500 years of measurement.
Fate and behaviour of selected organic substances in the urban drainage system. A. Welker*+
Presented by Antje Welker, University Kaiserslautern, Germany
For the presented study a set of „new“ substances was selected to analyze their origin and be-havior in urban water systems. The
consequences of different strategies for emission control in combined sewer systems are discussed by the example of these
substances. At first results of a literature survey on the occurrence of the selected substances in the main flow types of urban
drainage systems are presented. The results of measurement programs show a wide range of concentrations for various substances.
Main reasons for this divergence are different conditions of field studies in terms of investigation methodologies, site specific factors
and hydrological conditions. Followed by a summary representative concentrations in dry weather flow, surface runoff and WWTP
effluent pollution load were stated. Simulations for a fictive catchment (combined sewer system) were conducted. Three scenarios
were de-signed, that represent commonly used measures for emission control. For these scenarios an-nual pollution loads from CSO
structures and WWTP were calculated. The results are predominately dependent on substance properties like origin (dry weather
flow versus surface runoff) and the elimination rate in the WWTP. In summary the results give in-dications about possible strategies
to reduce pollutant emissions from combined sewer sys-tems. These are not only depending on the catchment conditions but also
extremely differ with the considered substance.
Modelling of snowmelt and rainfall runoff - Dynamics of road runoff and suspended solid transport. C. Westerlund*+; M.
Viklander; C. Hernebring
Presented by Camilla Westerlund, Luleå University of Technology, Sweden
In this paper, a simple model concept is presented to describe the dynamics of road runoff and suspended-solid transport from a
small urban catchment in northern Sweden. The study period stretches from March 28 to May 28, 2000, including both snowmelt and
rainfall. A modified degree-day method is used to describe the snowmelt and the transport of suspended solids is described by a
linear build-up function and a wash-off model. The model was verified through measurements taken from March 22 to May 22, 2001.
The results from the simulations showed that the simple model concept was capable of describing the dynamics of road runoff and
suspended solids rather well, based on the continuous course of events for the whole modelling period. However, if the model was
used for simulating a snowmelt period, or single events during snowmelt, the model approach would be too simple.
Results of full-scale tests of an integrated real-time control strategy for sequencing batch reactor plants. J. Wiese*+; J. Simon;
A. Welker
Presented by Juergen Wiese, ASA GmbH, Germany
This paper presents results of a research project, in which an integrated real-time control (RTC) strategy for a Sequencing Batch
Reactor (SBR) plant was realised in full-scale. By implementation of the RTC the hydraulic treatment capacity could be increased by
50 %. Furthermore, it was possible to improve the TN, TP and NH4-N treatment efficiency; the treatment efficiency regarding COD is
comparable. Consequently, it was possible to reduce the total emissions from sewer system and wastewater treatment plant (WWTP)
significantly.
Random number generator or sewer water quality model ?. P. Willems*+
Presented by Patrick Willems, Katholieke Universiteit Leuven, Belgium
Integrated urban drainage modelling and environmental impact assessment require sewer emission models to be linked with
submodels for treatment infrastructure and receiving rivers. The uncertainty in current water quality modelling is, however, huge,
and environmental impact assessment looses more and more credibility. Based on an integrated modelling case for a combined sewer
– WWTP – river system, it is shown in the paper that the integrated model does not produce more accurate results in comparison with
the random simulation of emission concentrations from a frequency distribution. This should, however, not pose a serious problem as
in most applications of impact assessment model results are not needed in real time but in statistical terms. Further investigation
makes clear that detail/sophistication in water quality modelling is not so important, but that more focus has to be given to longterm simulations, the use of parsimonious models and model validation based on concentration frequencies.
Relative comparison of different types of uncertainties in sewer water quality modelling. P. Willems*+
Presented by Patrick Willems, Katholieke Universiteit Leuven, Belgium
Quantifiable sources of uncertainty have been identified for a case-study of integrated modelling of a sewer system with a more
downstream wastewater treatment plant and storage sedimentation tank. The different sources were classified in model input and
model-structure uncertainties. They were quantified and propagated towards the uncertainty in the prediction of sewer emissions
(flow, and physico-chemical water quality concentrations and loads). Based on variance decomposition, the total prediction
uncertainty was splitted into the contributions of the various uncertainty sources and the different submodels. Although the results
strongly depend on the water quality variable considered, it could be concluded in most general terms that the uncertainty by the
water quality submodels is an order of magnitude higher than for the flow submodels. Future model improvement should therefore
mainly focus on water quality data collection.
Integrating Groundwater into Urban Water Management. L. Wolf*+; J. Klinger; I. Held; H. Hötzl
Presented by Leif Wolf, University of Karlsruhe, Germany
The management of urban groundwater resources is directly linked to urban water supply and drainage concepts. A proper
integration of groundwater into urban water management plans is recommended for long-term planning. The paper describes the
development of a new modelling suite which addresses the urban water and solute balance in a holistic way. Special focus has been
placed on the assessment of the impact of sewer leakage on groundwater in four case study cities. Tools for the prediction of sewer
leakage including the assessment of uncertainties are now available. Field investigations in four European case study cities were able
to trace the influence of sewer leakage on urban groundwater using microbiological indicators and pharmaceutical residues.
An overview of water sensitive urban design practices in Australia. T.H.F. Wong*+
Presented by Tony Wong, Monash University, Australia
65
Ecological Sustainable Development in Australia can be described as going beyond the protection of the environment from the
impacts of pollution, to protecting and conserving natural resources. In an urban environmental context this means urban
development (both greenfield development and urban renewal) that seeks to have no long term effects on various aspects of the
environment related to aspects such as greenhouse gas levels, material resources, biodiversity and ambient water environments.
Water environments, such as waterways and coastal waters, and water supply catchments are key areas where urban development
can have significant impacts. Water Sensitive Urban Design in Australia has evolved from its early association with stormwater
management to provide a broader framework for sustainable urban water management. It provides a common and unified method for
integrating the interactions between the urban built form (including urban landscapes) and the urban water cycle. This paper
presents an overview of current industry practice and research implementation of Water Sensitive Urban Design in Australia.
Flood control measures in Kuala Lumpur city centre. W. S. Wong*+; M. N. Zulkifli; K. W. Loke; N. M. K. Nik Hassan
Presented by Wai Sam Wong, Dr. Nik & Associates Sdn. Bhd., Malaysia
Due to rapid urbanisation in the Kuala Lumpur city, flooding has become very frequent and severe in the recent years that have
caused great economical losses and disruption to social activities. Immediate flood control measures have to be implemented and
because of the land constraint, the proposed measures have to be innovative to achieve the required protection level with minimum
disturbance to the present conditions. The project work involved a detailed review of previous studies and projects; rainfall-runoff
and hydrodynamic modelling; and development and evaluation of flood control options. The hydrological and hydraulic analyses; and
modelling simulations carried out have been based on very refined land-use cover data and application of innovative and soundly
based techniques. Innovative options have been investigated so that the measures will be based on flood detention concept at the
upper catchment to attenuate peak flood discharges flowing into the KL city centre. Flood bypass tunnel and diversion channels with
storages as well as deep pond detention storage are among the measures being recommended to solve the problem. Due to the
infrequent usage of the bypass tunnel for flood flow diversion, portion of the tunnel is also being utilised as motorway to make the
project more viable.
The evaluation of cost and benefits of structural stormwater best management practices. A. Wossink*+; B. Hunt
Urban stormwater runoff can be controlled by the use of various best management practices (BMPs). This papers presents an
economic decision making tool to answer the question facing engineers and developers as to what is the best BMP to choose given a
particular target pollutant and watershed as described by curve number range and soil type. The decision tool is applied for the
conditions of North Carolina, USA. The main findings are that (1) all the BMPs investigated, except for bioretention not in sandy soil,
displayed economies of scale, (2) no significant relationship could be assessed between removal efficiency and watershed size, (3) in
North Carolina, bioretention is, in general, the most cost-effective option for smaller watersheds, whereas wetlands are preferable
for larger wetlands.
Performance analysis of the Maclean Avenue detention tank, City of Toronto. L. Xu; B. J. Adams*+
Presented by Dr. Barry J. Adams, University of Toronto, Canada
The Maclean Avenue detention tank was constructed by the City of Toronto to decrease the frequency of beach closing caused by
directly discharged stormwater and CSOs in the Eastern Beaches area of the City. The purpose of this study is to evaluate the
performance of the detention tank for wet weather flow pollution control through a 5-year field monitoring program and to improve
the engineering understanding of such stormwater control facilities. Tank performance measures on runoff quantity control are
obtained from the analysis of 220 runoff events recorded in those five years, and the tank performance for pollution control is
subsequently calculated from the quantity control analysis results and influent and effluent EMCs. According to the specific
operational features of the Maclean tank and the principles of analytical probabilistic models, models are derived for both runoff
quantity control and quality control analysis of the tank. Field monitoring data are used to calibrate and validate the derived
models. A comparison among the observed results, predicted results from QQS continuous simulations and the derived analytical
probabilistic models is made and conclusions are drawn on the current performance of the tank and on the utility of monitoring and
modeling results.
A Proposal of Combined Separate Sewer System (CSSS). M. Zaizen*; Y. Matsumoto+
Presented by Yasutoshi Matsumoto, Takenaka Civil Engineering & Construction, Japan
With respect to the systems of urban drainage, two main systems have been adopted so far, i.e., combined sewer system (CSS) and
separate sewer system (SSS). Each of them has some merits and demerits respectively. Regarding the environmental demerits, the
CSS has a problem of combined sewer overflow (CSO), and the SSS has a problem of diffuse pollution. Then, what system is more
appropriate for urban areas? This paper describes a new concept of urban drainage system and important points to pay attention to
while evaluating the system. The system, here named “combined separate sewer system (CSSS),” is an essay on a new system of
urban drainage when planning newly developed urban areas by means of making use of existing technologies. And the paper also
searches for a possibility to adopt the CSSS to existing urban areas to improve the water environment.
Optimal control strategies for stormwater detention tanks. M. Zawilski*+; G. Sakson
The paper presents the results of optimisation of a combined sewerage system draining a real urban catchment in the city of Lodz.
Application of 8 storage tanks distributed on the catchment area and a single tank at the lower part of the cachment was analysed.
The calculations were performed using a set of historical rainfalls from the two-year period. Detention volume distribution across the
catchment and outflow characteristics of the storage tanks have an essential influence on the annual number of CSO events. The
effect of minimising the number of CSO events is greater in the case of a single storage tank. Adjusting the storage tank outflow can
both improve the results of the reduction of CSO events and minimise the annual CSO spill volume. A bit further improvement can be
obtained with the aid of RTC.
Trends in the combined sewerage development in the past and their importance for the present infrastructure. M. Zawilski*+
A short story of the combined sewerage system origin and developing is presented. The system introduced as a modern solution
about 150 years ago allowed for improvement of life conditions in many European cities. Designed for big flows, according to design
storms and constructed in densely built-up urban areas, it reveals serious problems today. Increasing ratio of the sealed surfaces
connected to the combined sewerage needs an urgent action in order to upgrade the whole system to meet the present regulations.
An upgrade plan for a combined system has been elaborated in Lodz, Poland to be implemented in next few years. Technical
problems connected with implementation of the plan in the present city infrastructure are discussed.
Integrated watershed-based drainage restoration planning. U. Zimmerman*+; F. Sieker
Presented by Ullrich Zimmerman, Ingenierugesellschaft Prof. Dr. Sieker mbH, Germany
For a watershed of 200 km² in south-western Germany, an integrated planning approach for retrofitting the sewer systems of ten
communities was developed. The planning objective was to optimize the water quantity and quality of the receiving waters by
minimizing the restoration costs for the communities. Seven different indicators (flooding, hydraulic stress, Nitrate load, Phosphorus
load, COD load, BOD load and the costs expressed as monetary values) were defined and six different retrofitting scenarios were set
up. The results were compared by multi-criteria analysis to determine the optimised solution for the entire watershed. To do this,
three different software models were coupled and a 30 year long simulation was computed. To summarize the results, it can be said
that source control measures, like swale and trench systems, have a stronger and more positive impact on the receiving waters than
the conventional measures. However, the optimised solution for a wide range of problems arising in a watershed will be several
measures tailored to site. This research work outlines the necessity and importance of an integrated watershed-based planning
approach and highlights the structure and needs to carry out such complex planning approaches.
Canada's CSO technologies manual - Framework for community action. G. Zukovs*+; J. Marsalek
Presented by George Zukovs, XCG Consultants Ltd., Canada
Municipal wastewater authorities are increasingly exploring new and innovative treatment technologies, which are specifically
designed for combined sewer overflows (CSOs). When applied as part of an overall wastewater management strategy, these
technologies can produce efficient and cost-effective solutions for CSOs. However, like all technologies they require systematic
design and proper operation. In many cases, the basic information needed by municipal decision makers and their engineers to
evaluate, select and design CSO treatment technologies has been difficult to assemble. In recognition of this need, the Government
of Canada through the Great Lakes Sustainability Fund has recently developed a CSO Treatment Technologies Manual, which should
serve to provide advice and guidance on the application of physical and physical-chemical technologies for the treatment of CSOs.
67
10th International Conference on Urban Drainage
Copenhagen, Denmark, August 21-26, 2005
Organised by
Section of Environmental Engineering
Aalborg University, Denmark
- in collaboration with
The Danish Water Pollution Committee (Spildevandskomiteen) and
The Society for Environmental Engineering (IDAmiljø) – The Society
of Danish Engineers (IDA)
Danish Water and Waste Water Association (DANVA)
Joint Committee on Urban Drainage (JCUD) of the International
Water Association (IWA) and the International Association of
Hydraulic Engineering and Research (IAHR)
The Urban Water Resources Research Council (UWRRC) of the
Environmental & Water Resources Institute (EWRI) of the American
Society of Civil Engineers (ASCE)
- and sponsored by
COWIfoundation, a commercial foundation which is a majority
shareholder of COWI A/S
CityNet, the Network of European research projects on integrated
urban water management, supported by the
European Commission under the Fifth Framework Programme, Key
Action "Sustainable Management and Quality of Water" within the
Energy, Environment and Sustainable Development programme
DHI Water & Environment
Krüger A/S
SAS - Scandinavian Airlines, the official airline for the 10ICUD

10 International Conference on Urban Drainage

Transcription

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