Manapakkam model: SWDs to replenish city waterbodies

The water crisis has finally opened the Greater Chennai Corporation’s eyes as it has started to connect storm water drains (SWDs) with the water bodies to save rainwater and to replenish groundwater.

In a first, the civic officials, with the help of local residents, have connected the storm water drains to Vannankulam pond in VGN Lakshmi Nagar near Manapakkam. A network of storm water drains with a total length of one kilometre has been connected to the pond that is spread over more than 2 acres.

“The project to link all storm water drains to waterbodies has been pending for long due to illegal sewer connections. Residents of VGN Lakshmi Nagar assured us of not letting sewage into the drain, following which we linked the drains and the pond,” L Nandakumar, Chief Engineer (Storm water drains), said.

However, the civic engineers have placed shutters at the mouth of two inlets into the pond to arrest the entry of sewage. The shutters will be closed except on rainy days. The drains have also been interlinked with a nearby waterway.

It is also learnt that the civic body has plans to implement a similar project in Velachery. “Storm water drains around Dhandeeswaram Temple Tank will be connected with the tank. We have found that the drains in the locality are free of illegal sewage connections. However, we will provide shutters at the entrance. The extra work would cost less than Rs 2 Lakh,” another engineer said.

Meanwhile, residents of VGN Lakshmi Nagar welcomed the move and said that the water from the recent rains was sent to the pond. “As the pond was so parched, rainwater percolated. Another spell of rain will fill the pond,” Sivakumar, a resident, said.

The Greater Chennai Corporation has undertaken the restoration of 210 waterbodies in the city and decided to link storm water drains with them. Apart from this, new storm water drains proposed in Kovalam and Kosasthalaiyar basins have been planned in a way to interlink several water bodies in the region.

“Linking storm water drains to waterbodies is the sustainable solution from water shortage. But, preventing illegal sewage lines is a challenge. We are trying to create awareness and with the help of residents, we will link drains to waterbodies step by step,” the engineer said.

Presently, the Corporation maintains 7,360 storm water drains extending over 1,894 kilometres.

KP Ramalingam, president, Natural Water Resources Protection Movement, emphasised the importance of maintaining feeding canals to the lakes and water bodies. “Apart from letting water from the storm water drains, the government should ensure the free flow of rainwater by maintaining feeding canals to the lakes. The feeder canals are also encroached by development,” he said.

In another initiative to increase the groundwater level, the civic body has also been creating rainwater harvesting structures in Corporation playgrounds, offices and parks.

“As many as 9,448 rainwater harvesting structures were built on roads, parks, Corporation offices and others. Of the total, 3,139 structures are on roads and civic body buildings have 2,071 rainwater harvesting structures,” Nandakumar said.