You can now prevent flooding and recharge your borewells all at once

While the focus is more on collecting rainwater from atop roofs, there’s much water being wasted as surface runoff during the monsoon.

With the growing water crisis in the city, Chennai Metrowater has called for residents to harness rainwater around buildings.

Pointing out that it adds to flooding on the roads, Metrowater is encouraging residents to sink recharge wells to improve groundwater levels and prevent rainwater from draining into the sea.

There are over 8 lakh rainwater harvesting structures in nearly 7.10 lakh buildings in the city. Metrowater plans to launch a campaign seeking residents to harness rainwater in every possible way.

The campaign will also include a random survey on the maintenance of the RWH structures, according to sources.

Given the average annual rainfall of 1,200 mm in the city, nearly 113 litres of rainwater can be collected in 1 sqft. of land per year.

Even if only 60 per cent of rainwater percolates in a plot measuring 2,400 sq.ft., nearly 1.62 lakh litres can be recharged per year.

Rainwater harvesting experts, however, say that driveway runoff should not be let into a sump or an open well unlike rooftop water that could be collected in tanks and used immediately. Sekhar Raghavan, director of Rain Centre, said water around the buildings is equal to that collected from the rooftop of a building.

A speed breaker constructed near the gate can work out to be a cheaper alternative to gutter arrangement.

Rain Centre can also be contacted for suggestions regarding RWH systems at 2491 8415 or 96770 43869.

Residents may also contact Metrowater at 2845 4080 or 4567 4567 for clarifications.

Metrowater plans to launch a campaign to get residents to harness rainwater in every possible way