Ecosystems as Infrastructure

Transcription

Ecosystems as Infrastructure
By Eric Lohan and Will Kirksey
Living Machines Systems, L3C
1180 Seminole Trail, Suite 155
Charlottesville, VA 22901
434.973.6365
www.livingmachines.com
Overview:
Nothing is as important to living organisms as
water. Water also serves as a crucial design
element to advance green building as an
integrating element of natural and human
ecosystems. In fact, recent innovations in
integrated water resource design and advanced
ecological wastewater treatment systems allow
using “Ecosystems as Infrastructure”.
Water has only recently become a consideration
for green building. Individual facilities
have usually been a part of a larger water
infrastructure. Now in many regions, that
larger infrastructure is overtaxed, aging, and
expensive to maintain. At the same time,
fresh water resources are being stressed
as demand outpaces replenishment. New
ecological engineering approaches such as Living
Technology® from Living Machine Systems allows
green building advocates to directly address
water problems at the facility and community
level.
The emerging ecological model of water and
wastewater infrastructure is analogous to the
structure of ecosystems. Natural ecosystems
are decentralized and composed of large
numbers of diverse, fractal components that use
and reuse water, energy, and materials locally.
The streams and rivers in a region display a
decentralized structure of repeating patterns
at different scales and nutrients are utilized
and recycled all along the way with natural
environmental processes.
Likewise, human water and wastewater systems
can be decentralized and can utilize ecological
treatment technologies. To be successful this
model requires maintaining and even improving
on the public health advances that were
obtained by the centralized municipal systems
in the past. Work is underway in a variety of
quarters to develop the new standards, new
regulations, new tools, new partnerships, and
new technologies that are necessary.
This new approach has the potential to
fundamentally transform our relationship with
water. The ‘once-through’ centralized approach
is giving way to an emerging movement toward
decentralized wastewater treatment and
reuse. This movement is spreading just like
the succession process of new species in an
ecosystem. These decentralized, ecological
systems are saving water, energy, and money
while supporting sustainable community
development.
Sustainably regenerating our watersheds
requires a functional and effective
water infrastructure using a full range of
decentralized, cost-effective technologies.
Advanced ecological wastewater treatment
systems are especially appropriate in this role.
Recent innovations allow the packaging of
enhanced, complex ecosystems to be applied
as reliable water treatment systems. These
treatment systems offer significant advantages
as fractal components of an integrated network
of treatment units deployed to improve the
regional ecosystems and watersheds.
The Conventional Approach:
The current centralized approach, with
some exceptions, is focused on large-scale,
centralized systems, using water once before
sending it downstream, and treating all
water to drinking standards regardless of
intended use. In many areas, this approach
requires moving water long distances, with
obvious high consumption of energy, and using
treatment technologies that also are large
energy consumers and usually generate a large
quantity of sludge needing further treatment
and disposal. Many scientists, engineers,
and community leaders are now aware that
continuing this approach to water infrastructure
isn’t sustainable. It can’t continue to deliver
the quality, quantity and consistency of water
we currently consume, much less meet the
demands of the future. Furthermore, we can’t
afford to maintain and expand this system.
http://www.livingmachines.com
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The current model outlined in Figure 1
is complex, energy intensive, and water
inefficient. The explosive growth in population
and economic activity over the past century is
overwhelming the ability of centralized systems
to serve the need. Limits are appearing that
were unimaginable 100 years ago. For example:
•Water resources are declining in quality
and quantity – the ‘once-through’ model of
centralized treatment is outpacing watershed
regeneration.
•The capacity of receiving waters is being
exceeded – the quantity of waste is so large
in most places that dilution is no longer
adequate.
•Centralized systems have large greenhouse
gas impacts from energy consumption and gas
emissions.
•Large quantities of sewage sludge are being
produced, requiring further treatment and
disposal
•Maintenance and new construction costs are
becoming intolerable1
Simply put, our centralized water system is
reaching the point of diminishing returns;
resources have become constrained, and we
can’t sustain even current levels of performance
in the future. We need to think about creating
smarter, more natural wastewater treatment
approaches.
The Ecological Model – Decentralized
Infrastructure Systems:
An alternative approach for wastewater
treatment is to apply an ecological model to
wastewater infrastructure. This model applies
ecological concepts to both the design of the
regional infrastructure and the design of the
specific treatment processes. The ecological
1 Water systems are showing evidence of a basic
principle of general systems science: as size increases
linearly, the cost to grow and maintain a system tends to
increase exponentially. The USEPA estimates that if capital
investment and O&M costs remain at current levels the
gap in funding for 2010-2019 will be almost $600 billion
for water and wastewater infrastructure.
model aims to integrate the best of existing
infrastructure with new decentralized water
management and treatment systems. This
integrated network will be designed to
supplement, protect, and restore natural water
cycles by treating pollution near the source
and reusing water locally. This promotes
an integration of human and ecological
communities into one water-based framework.
Natural streams and rivers display a
decentralized structure of repeating patterns
at different scales. Small streams or brooks
may transport entrained sediments or nutrients
to wetland areas scattered throughout the
upper reaches of the watershed, which help
improve water quality. At other points in the
watershed, when seasonal rains raise water
levels, riparian floodplains slow the flow rate
of the river and intercept large amounts of
sediment and nutrients. If one component of
this process is impaired there are numerous
back up components at the same scale or
different scales that can rebuild the lost
capacity. Integrated strategies for decentralized
wastewater treatment and water reuse at
multiple scales can mimic this approach
improving the overall effectiveness of our water
infrastructure (Figure 2).
A broader recognition and application of this
new approach requires improving awareness of
the possibilities among the major stakeholders.
A new decentralized wastewater strategy must
be put in place that is cost-effective, safe,
technically sound, and sustainable economically
and ecologically. Such a strategy will include
and maintain the best of the current systems
and existing tactics, such as low impact
development and water conservation. In
addition, continued, reliable access to water
requires the new approach to be resilient in the
face of changing regional conditions and help
deal with ongoing drought and water scarcity
challenges.
Beyond being a well-conceived approach to
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Figure 1. Conventional centralized wastewater treatment and disposal model ©Worrell Water Technologies
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Figure 2. Ecological decentralized wastewater treatment and reuse model ©Worrell Water Technologies
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providing water, the new water strategy must
also contribute to addressing other interrelated
issues such as energy, climate change, and
economic strength. An ecologically based model
of wastewater treatment infrastructure has the
potential to meet all of these goals. Significant
work is underway by a number of organizations
and associations, notably including the Alliance
for Water Stewardship and the Consortium
of Institutes for Decentralized Wastewater
Treatment.
The Ecological Model – Treatment Technologies
The ecological model can be applied not only
to the design of regional infrastructure but
also to the design of wastewater treatment
technologies that play a pivotal role in these
larger systems. Most centralized or municipal
treatment facilities use an activated sludge
approach to wastewater treatment. This
technology uses diffused air to accelerate the
growth of bacteria and the removal of nutrients.
It requires a very small footprint but uses a
large amount of energy. This conventional
process is most stable at larger scales. Smaller
decentralized applications require much greater
operational attention and may not be able to
consistently meet the water quality standards
required for wastewater reuse.
natural treatment processes in nature using
more complex communities of bacteria, other
microorganisms, and plants living on rock
aggregate to remove nutrients.
Early systems were energy efficient but required
a very large footprint and hence were not
appropriate for suburban or urban applications.
A new generation of advanced wetland
treatment processes have been developed which
turbo-charge wetland processes with the use
of high efficiency pumps. These systems are
high-performance and reliable combinations of
ecological science, engineering, and information
technologies.
Tidal wetlands (see the Living Machine®
description in the appendix) are among the most
efficient of ecological treatment processes.
Tidal wetlands reduce the footprint of early
wetland designs by 80%, yet require less than
25% of the energy of MBRs. These systems can
be readily incorporated into urban and suburban
sites due to the compact footprint. Because they
are also beautiful in addition to being functional
they have been incorporated into site design or
even into building architecture as atria.
The evolution of this technology over the
last two decades has allowed decentralized
treatment systems to be much more widely
applicable. The activated sludge process has
been modified with the addition of membrane
filtration technology to create Membrane
Bioreactors (MBRs). These membrane filters
help polish effluent from the activated sludge
treatment process creating consistent high
quality effluent required for reuse and further
shrink the footprint of activated sludge systems;
but, they also increase the energy requirements
of an already energy intensive process.
Making the Transition
Water issues are among the most complex
facing our communities right now, combining
environmental, economic, and human health
factors. Addressing these issues with the
conventional approaches isn’t working, but
the necessary evolution requires substantial,
coordinated effort – both bottom up and top
down. In particular, we need to reexamine and
update policies, design standards, engineering
models and analysis tools, monitoring and
control technologies, funding programs, and
management structures to support decisionmaking and maintain quality and public health
standards.
Another approach has been adopted in the
development of advanced wetland treatment
systems. Wetland treatment systems mimic
These efforts are much too extensive to detail
here, but the following areas need to be
addressed:
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• Design standards– technical examination
and expansion of existing design standards
by engineering societies and research
organizations; creation of new standards
as necessary to ensure that there are
clearly defined performance standards that
protect public health and the environment.
• Engineering models and technologies –
develop new analytical tools, information
systems, construction techniques, remote
monitoring and control methods, and
performance tracking approaches. These
should improve the ability to evaluate,
design, build, and operate individual
treatment systems as well as integrated
regional wastewater ecosystems.
• Funding programs – examine government
funding and grant programs to remove
barriers, equalize subsidies, and
provide a level playing field for funding
decentralized, ecological treatment
systems.
• Management structures – experiment
with new ways of management, ownership,
and operations of regional systems. For
example, centralized management and
ownership of decentralized systems by
a municipality or regional authority may
offer advantages in cost effectiveness,
quality control, and coordination of
treatment. In other cases, ownership by a
cooperative or by a DBOO (design, build,
own, operate) private utility company
could be appropriate.
• Policies– review of the laws and
regulations governing water and public
health to identify and remove unwarranted
barriers to adapting innovative
technologies while continuing to ensure
protection of the public. The lack of unified
national or in many areas even state
standards for water reuse has hampered
development and implementation of new
technologies and systems. 2
2 A recent report commissioned by the Cascadia
USGBC ‘Code regulation and systemic barriers affecting
Living Building Projects’ identifies seven important steps
for modifying the regulatory environment to foster the
These efforts require the support of a diverse
group of professionals who need to be educated
on the current limitations of centralized
systems and both the strengths and limitations
of a decentralized ecological approach. New
partnerships are required to develop and
implement this approach. Professionals who will
play a key role in this process include:
1. Municipal water and wastewater officials
2. Environmental and public health
regulators
3. Environmental Engineers
4. Water resource specialists and planners
5. Architects and landscape architects
6. Engineering contractors and builders
7. Knowledgeable civic leaders
8. Progressive developers
9. Industry leaders
10.Wastewater treatment plant operators
The complexity of natural water systems, the
intricacies of existing water infrastructure and
the complicated existing legal and regulatory
requirements for water use, disposal, and
reuse rule out simple prescriptive qualitative
or quantitative standards for sustainable
water use and reuse. Despite these challenges
a few standards have been developed or are
under development that attempt to provide a
template for sustainable water infrastructure.
1. LEED – The US Green Building Council
(USGBC) Leadership in Energy and
Environmental Design (LEED) standards
are the most widely adopted and most
well developed standards for green
building. LEED standards promote
water efficient fixtures, xeriscaping,
and water reuse for irrigation, toilet
flushing, and other water reuse
requirements. Although these standards
have played a key role in launching
the green building movement in the
adoption of sustainable systems and technologies. These
steps are particularly relevant for supporting water reuse
projects and are described in Appendix 2.
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US, they have been criticized by water
advocates as water credits are more
difficult to achieve than others and are
frequently passed over.
2. Living Building Challenge – The
Cascadia regional group of the USGBC
has recently developed a new standard,
the Living Building Challenge (LBC). LBC
does not have elective credits but only
prerequisites. The water prerequisites
include:
Prerequisite Ten – Net Zero Water
100 percent of occupants’
water use must come from
captured precipitation
or reused water that is
appropriately purified
without the use of
chemicals.
Prerequisite Eleven – Sustainable
Water Discharge
100 percent of storm water
and building water discharge
must be handled on-site.
These standards set a much higher bar
for water reuse but may place unrealistic
expectations on small buildings. The LBC
is trying to solve watershed problems by
focusing only on the building scale, which
may not be the optimum approach.
3. Water Neutral – The LEED and
LBC approaches address the building
industry but many other industries and
development practices affect the water
cycles in our communities. A UNESCO
Working Group is developing criteria that
reflect a more comprehensive approach
to ‘Water Neutral’ development and
industries. They define three criteria:
1. Defining, measuring and
reporting one’s water footprint;
2. Taking all action that is
reasonably possible to reduce the
existing operational water
footprint;
3. Reconciling the residual water
footprint by making a reasonable
investment in establishing or
supporting projects that focus on
the sustainable and equitable use
of water.
4. Alliance for Water Stewardship
– While the approach developed
by the UNESCO group provides a
general template there are no binding
requirements to give the language
credibility. New water standards are
under development by the Alliance
for Water Stewardship an umbrella
organization that represents key water
and environment NGOs including the
Pacific Institute, The Water Environment
Federation, World Wildlife Foundation,
the Nature Conservancy, and the
European Water Partnership. The goal
of these standards is to apply the LEEDtype framework exclusively to water
infrastructure from a holistic and global
perspective. It could become a very
important tool.
Communities will need to draw from these
approaches and others to develop standards
that fit with their specific requirements. There
is no one size fits all solution but it is hoped
that tools developed will be flexible enough to
become widely applicable.
Adopting the Strategies
The implementation of an integrated water
strategy for a community or a facility
requires a basis of detailed knowledge of
water flows in community infrastructure and
the in the surrounding environment. This
information may be developed from a number
of sources depending on scale. Regional GIS
databases often contain a wealth of important
information about soil conditions, land use, and
development. Weather data can be applied to
identify opportunities for rainwater harvesting.
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Utilities are increasingly using information
management systems to streamline utility
operations. A variety of government agencies
maintain important information about water and
environmental quality including the USGS, EPA,
NOAA, and the NRCS.
Significant work is generally required by a
trained analyst to integrate the various sources
into an effective decision-making framework.
In addition, a sustainable water reuse plan
requires an understanding of the water usage
demands and projections for the future. Once
an accurate knowledge of water sources and
uses is obtained, it is possible to develop a
water budget or water footprint. This should
detail the sources of water used in a community,
including potential nontraditional sources such
as rainwater or stormwater, and potential water
reuse opportunities as well as a detailed view
of water uses. By identifying water sources and
sinks we can qualitatively match high quality
sources with uses such as municipal water for
potable applications and lower quality water
sources such as reclaimed water with uses such
as toilet flushing or cooling towers.
The second goal of the water budget is
quantitative and requires detailed calculations
or estimations of water sources and sinks and
allows the development of water efficiency
and reuse strategies which accurately match
water availability with water requirements.
Water budgets are necessarily linked to design
standards or goals. There are two common
interpretations of how to balance a water
budget, with respect to ‘developed conditions’
or ‘pre-developed conditions’.
In an example using the ‘developed conditions’
interpretation, the Thames Gateway Project,
a 40 mile redevelopment project along the
Thames Estuary from the London Docklands to
Essex, is proposing to increase density by 10
percent without increasing the total water use
of the area by implementing efficiency upgrades
in new and existing buildings. This interpretation
has been criticized because in many cases
developed conditions are unsustainable and
should not be used as a baseline even if new
development doesn’t make it worse.
By contrast a water budget from the Sustainable
Urban Design Plan for Lloyd’s Crossing, a
35-square-block mixed-use area of Portland
Oregon, developed by Mithun and a team of
green design experts targets pre-developed
conditions. Design targets reference water
flows and quality that would occur on a similar
area of undeveloped Oregon forest providing a
truly sustainable reference point (see Figures
3-5 for predevelopment, current conditions and
proposed development water budgets).
The water budget provides the framework for
designing sustainable water infrastructure.
This process entails designing infrastructure
systems and selecting technologies that achieve
the required flows and quality for each use.
At present there is no systematic process for
achieving this goal. As discussed above, this
process will entail a variety of stakeholders and
design professionals working closely together.
Only a few communities have begun to address
these questions so models are limited and
what may be ideal in one community may be
inappropriate in another.
A few key considerations should drive the design
of sustainable water infrastructure systems.
1. Infrastructure systems should
be designed to optimize their
interrelation with the natural
hydrologic cycle. Utilizing low
impact development practices such
as bioswales and other natural
stormwater retention or detention
strategies is one example.
2. Sustainable infrastructure systems
should be developed at multiple
scales and should be mutually selfreinforcing across all scales.
3. Water infrastructure should be
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designed to support local reuse of
water and nutrients to avoid the
high cost and energy consumption
required for long-distance water
movements.
4. Sustainable water infrastructure
systems should utilize technologies
that are also energy efficient and
cost effective from a capital and
lifecycle perspective. A number of
technologies such as desalination
sacrifice energy efficiency for
water efficiency and thus are not
likely to be successful long-term
solutions in many areas.
5. Innovative technologies and
systems must protect public health
as well as or better than existing
systems. These systems must
also foster public acceptance of
recycled or reclaimed water by
eliminating all odor and color from
water before reuse, even for nonpotable applications.
Implementing Technologies
selecting applications that are appropriate for a
given scale. Figure 7 provides examples of water
reuse process diagrams at three different scales:
building scale, institutional or community scale,
and municipal scale. Different technologies and
water reuse goals are appropriate at different
scales. The optimum overall performance
from a cost and water efficiency perspective is
achieved by developing appropriate projects at
a variety of scales.
For maximum effectiveness implementing new
technologies must be appropriately targeted.
The application of new decentralized treatment
and reuse systems should be focused in areas of
rapid growth or failing existing treatment (e.g.
septic systems or package plants), in regional
networks as a means of avoiding expansion of
a centralized plant and the interconnecting
infrastructure, and as stand alone applications
to serve specific needs. In this way they help
rehabilitate and extend the life of existing
critical infrastructure by reducing the load on
these systems.
At the core of sustainable water infrastructure
systems are decentralized wastewater
treatment systems. These systems are generally
composed of six discrete steps as represented
in Figure 6. Wastewater conveyance systems
collect and transport wastewater from a
variety of sources. Treatment processes include
physical treatment such as filtration, screening,
and clarification, which can remove inorganic
materials or larger organic constituents.
Biological treatment processes such as MBRs and
advanced wetland systems remove suspended
solids and dissolved organic constituents such
as carbonaceous materials, and nutrients such
as nitrogen, and phosphorus. After biological
treatment, final filtration and disinfection may
be required to remove any remaining viruses,
bacteria or other harmful microorganisms
These decentralized systems should be
constructed in the context of an integrated
regional natural and human ecosystem, so that
the design of specific wastewater treatment
technology can help integrate natural water
cycles with human and environmental needs.
In some cases, it may be appropriate to undo
or modify some of the existing infrastructure
with strategies such as sewer mining to reuse
water, removing water control structures, or
restoring natural water channels. Environmental
and infrastructure benefits can also be
designed to enhance the local economy. The
selection of wastewater treatment technology
can be coupled with the creation of business
opportunities and new jobs. By involving
community interests in planning of water reuse
opportunities it is possible to optimize the
creation and maintenance of livelihoods and
locally productive economic activity.
Implementation of these technologies requires
Opportunities to implement sustainable
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Figure 6. Decentralized wastewater treatment system components ©Worrell Water Technologies
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Figure 7. Example water reuse designs at three different scales: building scale, community or institutional scale,
and municipal scale ©Worrell Water Technologies
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infrastructure development and water reuse
will be different in each community but
will generally be easy to identify since we
collectively waste a lot of water. Four different
projects examples are described in Appendix 3
to illustrate projects in urban, suburban, and
rural areas from the Southeast to the Southwest
and the Rocky Mountains to the Northwest.
Conclusion
The members of the design community
have long been practical visionaries – seeing
alternatives for improvement and bringing them
to life, creating the future in the process. We
know that there is no desirable, sustainable
future without adequate, high-quality water
flowing through human society and through
the ecosystems that support it. It’s time
to accelerate the evolution of our water
infrastructure to an ecological model that will
be the basis of truly green building and green
communities.
Living Machine Systems, L3C, (and predecessor companies
under the same ownership) has been developing advanced
ecological wastewater treatment systems for 15 years.
Our signature technology, called Living Machines®,
integrates tidal wetland ecosystems, engineering, and
information technologies to create Living Technology®
These high efficiency technologies have been used to
treat wastewater from a variety of sources, including
municipal, zoos, animal shelters, and food production;
and have been applied to a variety of reuse applications
including irrigation, toilet flushing, cooling towers, and
wash water. Clients have included M&M Mars, the Port
Authority of Portland, Oregon, the San Francisco PUC,
Furman University, the Esalen Institute, the US General
Services Administration, Oberlin College, the US Navy, and
the Emmen Zoo in the Netherlands.
Eric Lohan is General Manager for Living Machine Systems.
Eric has worked for ten years on the development of the
Living Machine® technology and is coauthor of five patents
on advanced wetland technologies. Will Kirksey, PE is
Global Development Officer for Living Machine Systems
and Senior Vice President for WWT, the parent company.
Will has over 35 years of experience in environmental
engineering and policy, including senior roles with the
Florida Governor’s Office, Battelle Labs, and the Civil
Engineering Research Foundation.
Water is a common denominator demonstrating
that Human communities and the natural
environment are all part of the same ecosystem.
That is a powerful concept offering a
foundation for 21st Century design. Integrating
green community design with Ecosystems as
Infrastructure promotes viability, value, and
resilience in the relationship of nature and
human ecosystems.
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Appendix 1
Appendix 2
The lack of unified national or in many areas
even state standards for water reuse has
hampered development and implementation of
new technologies and systems. A recent report
commissioned by the Cascadia USGBC ‘Code
regulation and systemic barriers affecting Living
Building Projects’ identifies seven important
steps for modifying the regulatory environment
to foster the adoption of sustainable systems
and technologies. These steps are particularly
relevant for supporting water reuse projects.
1. Identify and address regulatory
impediments. Byzantine and in some
cases outdated standards for water reuse
are hampering the adoption of new
technologies and stifling innovation.
2. Create incentives matched with
goals. Water savings that accrue
from water reuse should result in
direct economic savings similar to net
metering approaches for solar energy.
Unfortunately this is not always the case.
3. Develop education and advocacy
programs. With proper training and
support the regulatory community
can become the strongest allies of
appropriate sustainable water reuse
technologies. Community leaders,
developers, and design professionals
would all benefit from understanding
more about successful new technologies
or applications.
4. Accelerate research, testing,
development, deployment, and
monitoring. States and particularly the
federal government need to develop
appropriate incentives to certify new
technologies to assure their performance
but also foster the development of
new technologies. This should include
appropriate consistency and reciprocity
among jurisdictions. Every new cell
phone does not have to undergo unique
performance and safety evaluations in
every US city in which it is sold.
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5. Create Green Zones, designated
sustainable development districts. There
are always risks associated with the
implementation of new technologies and
systems. The Green Zone model allows
new technologies to be demonstrated
on a provisional basis with adequate
regulatory oversight.
6. Facilitate the creation of a holistic
integrated regulatory process. For
water system approval there are
frequently overlapping and conflicting
water regulations for public health,
environmental protection, and resource
allocation. A holistic integrated
regulatory process would allow social
and environmental goals to be met most
effectively.
7. Ensure social equity in policies that
safeguard public health, safety, and
welfare. Frequently water reuse
practices are targeted at addressing the
needs of the wealthy (irrigation of golf
courses) while parks in working class
neighborhoods do not have access to
reuse water for irrigation. In the US and
globally the poor have disproportionately
born the cost of environmental pollution.
Appendix 3
Four different projects examples are described
below to illustrate projects in urban, suburban,
and rural areas from the Southeast to the
Southwest and the Rocky Mountains to the
Northwest.
Example Projects:
Oregon Health and Science University,
Portland OR
The Center for Health and Healing at the
Oregon Health and Science University along
the Willamette River in Portland is 16 stories
tall and totals about 400,000 square feet. This
structure uses a series of interconnected water
systems designed by Interface Engineering to
reduce municipal water use and to eliminate
surges of stormwater. While all potable water
comes from municipal supply, highly efficient
sinks, showers, and toilets are used throughout
the building, and rainwater is captured and
stored in a 22,000-gallon cistern for fire
suppression, HVAC (heating/ventilation/airconditioning) cooling towers, as well as radiant
cooling.
Collected rainwater is also used for a portion
of the toilet flushing demand and building
wastewater is treated onsite with an MBR in
the basement. Treated and disinfected water is
reused for toilet flushing as well as irrigation.
All wastewater is disposed on site through the
irrigation system. A green roof on the building
collects a portion of the rainfall and reduces
stormwater runoff. With these design changes,
the building’s potable water demand is reduced
by over 60% -- saving an estimated 5 million
gallons of water per year.
Guilford County Schools, NC
When a suburban school district outside of
Greensboro NC wanted to build a new middle
school and high school campus they estimated
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that sewer connection fees would be over $4
million dollars. They opted for a decentralized
approach to water reuse at less than one
quarter of that price. A 365,000 gallon concrete
rainwater cistern was constructed to collect
runoff from the roofs of both buildings. All toilet
flushing on campus is provided with rainwater.
The roof of the tank is used as a regulation size
basketball court. All wastewater is treated by a
Living Machine® advanced wetland treatment
system. The system is located between the two
buildings and provides aesthetic and educational
benefits in addition supplying irrigation water
for all of the school’s athletic facilities.
References
Dallas Animal Shelter, TX
Water Environment Federation www.wef.org
The Pacific Institute www.pac-inst.org
Alternet Water Blog www.alternet.org/water/
The City of Dallas recently built a new city
wide animal shelter to facilitate the care and
adoption of stray animals. This large facility
requires 10,000 gallons of water per day to
clean animal kennels. A reuse system was
built to collect and treat wash-down water
from kennel cleaning with a Living Machine®
Tidal Wetland system and a three-stage
disinfection system. Reclaimed water is then
reused for kennel washing. By reducing the
potable requirements for wash-down by up to
70 percent, this system saves approximately
1 million gallons of water per year, enough to
supply 100 homes.
BP, Casper WY
Significant water reuse potential exists in
industrial applications and in environmental
remediation. In Casper, Wyoming BP is spending
the next 100 years or more cleaning up
petrochemicals that have leached into the soil
and contaminated groundwater. They are using
an advanced wetland system designed by North
American Wetland Engineers that reclaims
almost 1 billion gallons of water per year that
is then used for irrigation of an adjacent golf
course. This energy efficient process was also
cost effective saving BP at least $12 million over
other alternatives.
Asano, T., F. Burton, H. Lerenz, R. Tsuchihashi,
and G. Tchobanoglous. 2009. Water Reuse:
Issues, Technologies, and Applications. McGraw
Hill Books, New York, NY.
Kadlec, R.H. and S. Wallace. 2008. Treatment
Wetlands 2nd Edition. CRC Press Boca Raton, FL.
Lohan, T. (ed) 2009. Water Consciousness.
Alternet Books, San Francisco, CA.
Vickers, A. 2001. Handbook of Water Use and
Conservation. Water Plow Press, Amherst, MA.
Nonprofit Organizations
Design Firms
2020 Engineering, Bellingham, WA,
www.2020engineering.com
Alliance Environmental LLC. , Hillsborough, NJ,
www.allianceenvironmentalllc.com
Interface Engineering, Portland, OR, www.
interfaceengineering.com
Mithun, Seattle, WA, www.mithun.com
Naturally Wallace, Minneapolis, MN, www.
naturallywallace.com
Sherwood Design Engineers, San Francisco, CA,
www.sherwoodengineers.com
Worrell Water Technologies, Charlottesville, VA
www.livingmachines.com
Water Standards
US Green Building Council www.usgbc.org
Cascadia USGBC and Living Building Challenge
www.cascadiagbc.org
Alliance for Water Stewardship www.
allianceforwaterstewardship.org
16
Living Machine STEP Sheet
Figure 1. Living Machine Process
1.
2.
3.
4.
5.
6.
Influent wastewater is collected from a variety of sources and flows into the Primary Tank.
Solids settle and are solubilized in the Primary Tank.
Effluent flows through a filter into the Recirculation Tank.
Influent is pumped to the Tidal Flow Wetlands (TFW) which alternately fill and drain providing an ideal
environment for bacteria and plants which consume nutrients in the wastewater.
After initial treatment in the TFW water is pumped to the Vertical Flow Wetlands (VFW). VFW remove
any remaining solids and nutrients as water trickles through the wetland.
After biological treatment in the Living Machine® wastewater may be disinfected before reuse for toilet
flushing, irrigation, cooling towers, washwater or other nonpotable applications.
© Worrell Water Technologies/Interface Multimedia
17
Figure 2. Comparison of wastewater treatment technologies based on energy use and footprint requirements for
a given volume of flow. Comparison was created at 100 m3 or 26,000 gallons per day © Worrell Water Tech-
18
Figure 3. Example predevelopment water budget from the Lloyd Crossing Sustainable Urban Design Plan and
Catalyst Project © Mithun/KPFF
19
Figure 4. Example current development water budget from the Lloyd Crossing Sustainable Urban Design Plan
and Catalyst Project © Mithun/KPFF
20
Figure 5. Example proposed 2050 development water budget from the Lloyd Crossing Sustainable Urban
Design Plan and Catalyst Project © Mithun/KPFF
21

Ecosystems as Infrastructure

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