Therefore, 85 per cent of the total rooftop and surface runoff is being harvested.
WATER SUPPLY SOURCE
The water requirement is fulfilled by four tubewells located in the premises and supplemented by municipal supply.
Around 5.5 lakh litres of water is used for daily requirements.
RAINWATER HARVESTING SYSTEM
Rooftop rainwater harvesting: Rainwater from the Row Houses and the Club building is flown into the storm drain that runs parallel to the northern boundary wall. The rainwater from the rooftops of B, C, D, E and G block along with the surface runoff from the paved area is flown into the storm drain. This water is harvested by constructing nine percolation pits within the storm drain or diverting water to nearby recharge wells at strategic locations. These pits are also provided with a recharge bore of 150 mm diameter and 10 m depth to facilitate the recharging of water into the subsoil strata.
Surface runoff harvesting: Surface runoff generated from the roads along with rooftop rainwater from B, C and D block used to cause water logging for hours unless pumped out near the abandoned gate. This water is now recharged through 4.5 m long, 1 m wide and 2 m deep recharge trench at the gate. The trench is provided with two recharge bores of 150 mm diameter and 18 m depth. Layers of pebbles and boulders inside the trench ensure better filtration.
The implementation was completed in August 2002 and the groundwater level, as in February 2004, was around 48.3 m below ground level (bgl).