The Greater Chennai Corporation (GCC), through the Integrated Stormwater Drain (ISWD) project of the Kovalam Basin, plans to prevent flooding and save rainwater which would go waste into the sea.
In a press meeting organised at the Ripon Building on Tuesday, Corporation Commissioner G. Prakash said as per a study done by the civic body for executing the ISWD project in the Kovalam Basin (divided into three packages of M1, M2 and M3), more than 86% portion of the M3 package located on the East Coast Road (ECR) side are occupied by concrete buildings and vacant lands. Areas such as Kottivakkam, Palavakkam, Neelankarai, Injambakkam, Sholinganallur, Kanathur and Uthandi have seen rapid housing development.
He said: “Of the total rainwater harvesting capacity calculated in the M3 package in the areas being 1,137 hectares, it has been found out that houses and plots occupy 980 hectares. Although these localities are located in sandy terrain, in the December 2015 floods several localities suffered severe flooding.” The flooding in 2015 showed that more than 60% of the rainwater of 470 million litres flowed into the sea with only 305 million litres percolating into the ground, out of total 775 million litres of rainwater realised.
However, the M3 package of the Kovalam basin would be using German technology of installing eco blocks and percolation pits for harvesting rainwater by which more than 325 million litres of rainwater would be harvested.
The Kovalam basin ISWD project involving 360 km is proposed to be executed at a cost of ₹1,243.15 crore. While the M1 and M2 packages would see ISWD being constructed in Perungudi, Pallikaranai, Injambakkam, and Madipakkam, under the M3 package ISWD would be built for 52 km at a cost of ₹270 crore. The civic body would very soon appoint a project management consultant for monitoring and executing the work.