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Disaster Resilient City Development Strategies for Sri Lankan Cities
1. Background of the Project
The township of Balangoda is situated at Rathnapura district, 145km away from
Colombo and 44km from Rathnapura in Sabaragamuwa province of Sri Lanka. It is a
significant commuter point for the people who passing Colombo – Badulla (A4) main
road and also a connective gateway between the rural regions of the surrounding.
The routine functions of Balangoda town have been interrupted at many times in the
past few years due to the flooding of ‘Dorawela Oya’ that flowing through the town.
The absence of the smooth flow of the stream is the foremost reason for this and the
following facts are also contributed to this.
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The destructive erosion of the stream bank in several regions
Obstructive growth of vegetation on the stream banks
Debris fallen in to stream
The stream has exposed to fill due to gem mining in upstream
Sand and remains of washed lode are depositing on the stream bed, resulted
on dropping the capacity of the stream
The program of Disaster Resilient City Development Strategies for Sri Lankan Cities is
engaging to overcome this phenomenon with long term solutions including mitigation
for avoid flooding, avoid the erosion and collapse of the stream bank, enhance the
water quality of the stream, with the intention of providing risk free, functional and
aesthetical backdrop to the city for the future development.
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Disaster Resilient City Development Strategies for Sri Lankan Cities
2. Significance of the township of Balangoda
Geo-morphological Importance
The Balangoda region is situated in the boundary between the Second Peneplain and
the Third Peneplain in Sri Lanka. In Kalthota area, it can be seen very sharp boundary.
The elevation of the uplands ranges from 270m to 1060m above mean sea level. An
escarpment over 100m high separates the lowland from the uplands, which can be
seen continuously at Kaltota and Minipe.
Geological Importance
Geologically Balangoda lies in the highland series of
the Sri Lankan Precambrian complex comprising
metamorphic rocks, which have been folded in to
form the Balangoda syncline. Also, the boundary
between the Highland complex (HC) and Vijayan
complex (VC) lies on this area. Due to that, the
surrounding is rich with mineral deposited sites such
as;
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Calcite Mines – Piyangiriya
Sedimentary Limestone Deposit – Illukpelassa
Calcite mines – Illukpelassa
Feldspar and Quarts deposits – Thanjanthenna
Pegmatite with Gem Mineralization – Thanjanthenna
Kaolin deposit – Kirimatithenna
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Disaster Resilient City Development Strategies for Sri Lankan Cities
Historical Importance
There is evidence of Paleolithic (Homo
Erectus) people in Sri Lanka about 300,000
BP and possibly even as early as 500,000 BP.
There is strong evidence of prehistoric
settlements in Sri Lanka by about 125,000
BP. Anthropologically modern human
remains have been found which have been
dated back to the subsequent culture of the
second Stone Age period - which appears to
have endured until about 1000 BCE in
Sri Lanka with the transition to Iron
working. This Mesolithic culture was known
as the Balangoda Culture.
The Balangoda Man appears to have been responsible for creating Horton Plains, in
the central hills, by burning the trees in order to catch game. However, discovery
of oats and barley on the plains dating to about 15,000 BCE suggests that they also
may have engaged in agriculture. The place called Bellan Bandi Palassa is also situated
near Balangoda town.
3. Present situation
The economy of the region is mainly dependent on farming and mining. The thing is
that most of mining sites are not well ordered or not properly prevailing any kind of
environmental or geological protective procedures. Some areas were abandoned after
excavating and those are highly potential for geological hazards like earth slips,
erosions, floods & landslides etc. So a proper awareness about those things and
proper guidance is a must.
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Disaster Resilient City Development Strategies for Sri Lankan Cities
4. Conceptual Background
As affirmed by these facts, Balangoda is a unique area in Sri Lanka with a rich historical
character and a unique geological & natural topography of great diversity. It should
also be noted that this area is also more vulnerable to disasters such as landslides,
erosions, floods etc which may be the result of improper development.
Therefore any large scale intervention in terms of design; be it engineering, urban
design or landscaping, it should take into account this significant character of the
region with its strengths and vulnerabilities, in order to result in a suitable and
successful design solution. The proposed conceptual solution was developed based on
the recognition of this uniqueness, as an intervention that is partially derived from that
nature.
To enhance Balangoda township and it’s geo-morphological, historical values, while
creating awareness on erosion mitigation and flood controlling methods in the
general public.
A Theme Park..!!!!
5. Design Concept
A City Park for Stream Preservation – “Functional Aesthetics for the city”
In its present condition, the stream known as ‘Dorawela Oya’ is in need of certain
mitigation interventions to prevent erosion and collapse of stream banks. These
methods must be integrated into the existing city landscape in the form of a Park
which functionally but unobtrusively introduces the mitigation methods into the place,
more significantly for the awareness of the target community.
The integral methods will be environmentally viable and of self sustaining nature with
minimal maintenance requirements in long term. The proposed mitigation solutions
will therefore;
Form a pleasant, contextually sensitive urban parkland
Be a unique mitigation solution that responds to the functional aspects of
the stream along its length
Be ecologically friendly and discourage unplanned intervention while
successful sustaining itself
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Disaster Resilient City Development Strategies for Sri Lankan Cities
Disaster Mitigation
Environmentally
Viable methods
Environmentally
Viable methods
‘CITY PARK’
Landscape design
solution with
“Functional
Existing &
Aesthetics)
Public
Proposed city
Awareness
functions
Water quality
improvement
6. Zoning the stream environment
The stream area is presently needed for many human activities, and the proposed
mitigation solutions will classify the human activities which are positive and negative.
The stream area will be zoned based on these activities and its impact on the stream
side.
High human permeability areas with un-restricted access to the stream –
Public gathering areas of recreational nature (eg: Play Ground area)
Low public permeability areas where access is available but discouraged –
Existing market (Pola) and bus stand region where the stream becomes
vulnerable to littering and pollution
Non-permeable areas with no access to the stream bank –
These are areas where human trespass in unwelcome, such as the water
retention and overflow zones
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Disaster Resilient City Development Strategies for Sri Lankan Cities
7. Project Summary
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Existing
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Unplanned / degenerative intervention.
Deliberate ignoring of the canal's condition
Result
Natural and human crisis through flooding, pollution,
degeneration of the town environment
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Disaster Resilient City Development Strategies for Sri Lankan Cities
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Solution
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Beyond mitigation
Effective, sensitive, practical mitigation methods
A pleasant, functional, effective, urban landscape
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Disaster Resilient City Development Strategies for Sri Lankan Cities
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Spatial use in harmony with the need of mitigation
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Environmental compatibility of the
'green solution' coupled with effective engineering solutions
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ALLOCATED BUDGET: 8 MILLION LKR
LAYOUT PLAN
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High human permeability areas
Low public permeability areas
Non-permeable areas
Disaster Resilient City Development Strategies for Sri Lankan Cities
8. Layout Plan & Landscape Design Proposals
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Disaster Resilient City Development Strategies for Sri Lankan Cities
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Disaster Resilient City Development Strategies for Sri Lankan Cities
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