SOAK AND SQUEEZE THE GREEN

University of Moratuwa (UoM), Faculty of Architecture, Department of Architecture, Moratuwa

Project idea

SOAK AND SQUEEZE THE GREEN

PROJECT TYPE:
WETLAND RESTORATION PROJECT (ECOLOGICAL)

SITE:
KIRALA KELE, MATARA, SRI LANKA

PROJECT CONCEPT:
“REJUVENATION OF A MAL-FUNCTIONING SYSTEM INTO A MULTI-FUNCTIONING SYSTEM FOR IT’S PROTECTION”

PROJECT OBJECTIVES:
PRIMARY:
01. Supports the protection of wetland and marshlands:
- By controlling the ongoing activities that may cause the destruction and loss of wetland (Such as landfilling, Removal of vegetation, Bird hunting, Ongoing criminal activities)
SECONDARY:
01. Increase the wildlife value of the area by recreating the space.

02. Raise public awareness:
- Educate people about wetland and its values
- Reduce or change their ecosystem-damaging practices

03. Let the landowners know that wetlands are recognized as a valuable and essential part of the ecosystem.

Kirala kale is a marshy wetland system and a mangrove forest. And this is the most conservation area in Matara city. It covers an area of 1800ha which is accessible from,
Matara – Akuressa road (A24)
Matara – Hakmana road (B535)

It is comprised of Marshlands, Mangrove habitats, Paddy lands, Irrigation canals which is located in the right bank, lower catchment area of the Nilwala river. Home gardens can be found in the immediate boundary. And also, it is in the same level with the sea.

Kirala Kele was published as a protected area in 2003. now it is under the control of the wildlife department, Mirissa branch. Nilwala flood protection scheme has changed the eco-system of the wetland area.

Location:
Kirala Kele is located 3Km away from Matara District.
Latitude: 5°58'32.98"
Longitude: 80°31'43.13"

Area: 1800 Hectares
Sanctuary area: 310 Hectares
Population: 35,000

Context Analysis:
Hydrology - This site acts as the sponge of the whole Matara city. When the water level of the Nilwala river rises during rainy seasons, the excess water is released into Kirala kele. During wet seasons, the wetland absorbs excess water. Later when the water level of the Nilwala river drops lower than the Kirala kale during dry seasons, retained water is pumped back into Nilwala river. There are two main irrigating canals as inlets. The two main outlets are:
01. Thudawa pump house. Started in 1983. 8 pumps. rate: 4 cumec discharge
02. Gravity outlet. Started in 1993. 5 gates. rate: 16 cumec discharge (19.2 m3/s)

After the devastating flood in 1969 in Matara, the Nilwala Flood protection scheme was initiated in 1983 as a solution for the frequent floods. During this project all the canals were excavated much deeper and the acidity of the soil rose causing the pH value of the soil to drop. As a result of this, currently most of the paddy fields in this area has been abandoned and they've turned into marshlands. As a result of the Nilwala Flood protection scheme, a well-organized canal system has been formed. There are three main canals named S, T and U. There is also a secondary canal system of length 48km.

Project description

PROJECT TYPE:
WETLAND RESTORATION PROJECT (ECOLOGICAL)

PROJECT CONCEPT:
“REJUVENATION OF A MAL-FUNCTIONING SYSTEM INTO A MULTI-FUNCTIONING SYSTEM FOR IT’S PROTECTION”

Project Identification:
Kirala Kele is a site that has more potentials. Bird sanctuary is a main strength of the site. This site is on its way to destruction due to land fillings and human encroachments. Abandoned and degraded lands are the ones facing direct threats. To overcome this challenge, a functional site must be established by creating a sustainable ecosystem. When consider the migration routes of birds, Kirala Kele is one of the pieces in the chain of Western route to Bundala which is widely used by migrating birds to reach Sri Lanka. Without Kirala Kele, the chain breaks down because all these places are like steppingstones in this route. This shows how important this site is to Sri Lanka and that is the basis of this project.

Identified threats:
This land was a paddy field before. But due to water and soil problems it has turned into a marshland. A marshland is a very important eco-system that has good potentials. As this land is a marshland, this will soon become a habitat for native people if not protected properly. Because it is an abandoned paddy land at the moment (Higher human influence). If that happens, it will be a major threat to the whole Kirala Kele area. Therefore, we have to protect this site(Marshland). If the surrounding paddy fields also turn into marshlands, they will also face the same threat mentioned above. The main reason for this abandoning of the paddy fields is the water problem. Therefore, the main idea behind this project is to formulate a design to protect this marshland while, rectifying the water problem which can protect the surrounding paddy fields as well. Develop the site to protect the marshy eco system, while providing quality water supplies to the surrounding paddy lands, before turning those paddy lands also into marshlands.

Technical information

Master Proposal:

Past, The whole area of the Kirala Kele has been a sustainable area, where more than 5000 acres of land was cultivated by the people who live in the surrounding areas.

Current situation, Out of the cultivated area, most parts have been abandoned due to the rise of acidity of soil as a result of the Nilwala Flood Mitigation project. This has caused those paddy fields to turn into marshlands. And, numerous species of invasive plants has rapidly spread, and this has resulted in malfunctioning of the wetland system. Invasive Plants:
- Acacia saligna
- Panicum maximum
- Typha angustifolia
- Lantana camara
- Eichhornia crassipes
- Alstonia macrophyla

Future, The mission of the project is to introduce a pilot project to a selected potential site, which can provide a sustainable eco-system to the Kirala Kele area and can be applied to the whole context of Kirala kale, by addressing the identified issues.



DESIGN BRIEF:
Primary outcomes:
• Ecological sanctuary.
• Bird watching sanctuary.
• Wetland promenade.

Secondary outcomes:
• Observatory.
• Bird watching.
• Butterfly watching.
• Sound scaping.
• Research facilities.
• Places to gain experience.
• Visitors center.

Ecological functions:
• Water purification.
• Treating anthropogenic discharges (storm water / wastewater)
• Natural water cleansers – Biological : plants, Chemical: microbes
• Pollutant transformation: - Bio filters , Bio absorbers
• Phytoremediation techniques (Phytotransformation, Phytodegradation)
• Provide wildlife habitats.
• Improve water retentions.



TARGET USERS:
Primary:
Local and foreign visitors in the form of observers, bird watchers and researchers are the Primary Target Users of this design.

Secondary:
Residents of the surrounding neighborhood will have new job opportunities as well as indirect opportunities for an extra income. Guiding, maintenance staff and security are direct job opportunities while handicrafts made of natural materials like “Pan” and native beverages like “Kirala Juice” are some of the indirect entrepreneurship opportunities.



SOFTSCAPE CONCEPS:

01. Tree Tunnel Areas:
- Tree avenue system
- Provide shade
-Different trees provide different senses

02. Canal Edges:
- As an ecological boundary

03. Pond Edges:
- As an ecological boundary

04. Canals and Ponds:
- Using submerged and emergent plants to reduce the water flow

05. Floating Wetland:
- Plants as biofilters
- Plants as bio absorbers

06. Ecological Skin:
- Covering hard edges by using soft edges

07. Marshland Areas:
- Creating the self-sustainable ecotone



HARDSCAPE CONCEPTS:

01. Manmade Architectural Structures:
- Covered with an ecological skin

02. Manmade Structures and Other Elements:
- Oriented and designed to capture the best image of the surrounding

03. Elevated Walkway Along the Wetland:
- It is not highlighted, but provide safety and the sense of direction