Spinal Injury Centre's Rainwater Harvesting System

RAINWATER AVAILABLE FOR HARVESTING

Total area - 52,598 square metres (Sq m)

Average annual rainfall in Delhi - 611 millimetre (mm)

Total volume of water harvested - 27,317 cubic metre (m³) or 273,17,000 litres

This represents 85 per cent of the total rainwater harvesting potential.

WATER SUPPLY SOURCE

The Centre's water requirements are met by four borewells located on the hospital premises.

RAINWATER HARVESTING SYSTEM

Hospital building:

The rooftop rainwater and the surface runoff from the western part of the building are drained into a stormwater drain that runs to the west side of the building. This water is diverted into a recharge well located at the northwest corner of the campus near an existing borewell. A part of the rooftop rainwater from the east side of the hospital building and runoff from the paved area are diverted through a network of pipes and collection chambers to another stormwater drain that runs to the north of the premises. This runoff is also diverted to the same recharge well located near the borewell. This recharge well is 2.75m in length and 2.13m in breadth and is 1.82m deep. This recharge well is provided with a recharge bore of 100mm diameter and is 20m deep. This recharge well has two compartments, and the runoff water undergoes two stages of filtering before it enters the recharge borewell. Layers of brickbats and sand ensure the quality of water used for recharging purposes.

Staff quarters area:

The rooftop rainwater and the surface runoff from the paved and unpaved areas are collected in chambers interlinked by pipes. This water is used for recharge purposes by diverting it to two recharge wells. Part of this water is diverted to recharge the east side of the staff quarters and the rest is harvested by converting a dry borewell into recharge well near the entrance of staff quarters. These recharge wells are measure 1.5m in diameter and are 2m deep; the recharge borewell measures 20 meters.

The implementation was completed on October 2002 and the water level on February 2003 was measured at 32m below ground level (bgl).

The cost of the entire rainwater harvesting system was Rs 0.80 lakh.

IMPACT

Water level data

This project confirmed that is is possible to arrest declining water levels through rainwater harvesting. Before the system was implemented, the water level in the hospital stood at 32.2m below ground level (bgl) in April 2003. Concerned with falling water levels, and with growing dependence on groundwater, the Indian Spinal Injury Center's authorities decided to adopt rainwater harvesting on the hospital premises.