CHENNAI: Neighborhoods on East Coast Road (ECR) to soon get an eco-friendly drain network to get rid of overflowing drains.
The new network will be a combination of drains made of melted plastic, rubber and electronic waste; rainwater harvesting system, artificial wetlands, sponge parks and a series of recharge wells ideal for a sandy soil. The drains tried out abroad will help prevent polluted water from being let into the sea and will also spare the area of ugly box-type concrete drains.
Taking note of suggestions from the National Green Tribunal’s expert committee and the Tamil Nadu coastal zone management authority (TNCZMA) to implement eco-friendly and sustainable solutions along the ECR, the Greater Chennai corporation has proposed to set up natural infrastructure instead of concrete box drains along the sandy Kovalam basin.
Since 46 outfall locations of the conventional drains are breeding spots of Olive Ridley turtles, the civic body has junked the concrete drain project in Kottivakkam, Palavakkam, Neelankarai, Injambakkam and the KfW experts have started preparing a project report for eco-friendly drains.
“Wherever possible, we will set up eco-blocks and infiltration tanks that will allow rain water to flow and collect in artificial ponds. Vegetation beds such as tree plantations will be used in locations where there is minimal or no water stagnation. In areas of heavy inundations, artificial wetlands will also be set up. Sponge parks that include an urban park space with tanks, greenery and water beds to soak up rainwater will also be set up. All the road run-off will be stored there for a period of time reducing water stagnation,” said chief engineer S Rajendiran.
RR Sivaram, rain water harvesting expert, said that the new system “will increase groundwater recharge and reduce flooding at 15-20% lower cost with a longer shelf life.”
Manushi Ashok Jain, co-founder and director of Sponge Collaborative, working on a sponge park in Kosasthalaiyar basin, said, “Costly gray infrastructure investment has very limited co-benefits and high likelihood of failure due to limited options with recurrent maintenance costs. A blue-green infrastructure can reduce costs, environmental impact and create several benefits in terms of public health, biodiversity, reducing heat island effect, reducing pollution and building resilience. This approach has been widely implemented in China with constructed ponds and wetland parks in more than 20 cities, anti-flood parks in Thailand, cloudburst parks in Copenhagen, and river parks in Singapore as part of the Active, Beautiful, and Clean Water Program. ”
Sushma, a resident from the area said, “It is great that the citizens’ voice is at last heard. However, eco-blocks are not eco-friendly as the name suggests and should not find a place near the ocean or beach.”
The steering committee that met last week has approved the KfW proposal and has asked them to study and produce a detailed project report. “Once they submit it, we will go ahead with the project,” said an advisor of the Thirupugazh committee.