RAIN WATER HARVESTING

It is a technique of increasing the recharge of ground water by capturing and storing rain water in specially constructed structures.

Objectives:•To reduce of run-off loss & to avoid flooding.•To meet the increasing demand of water.•To raise water table by recharging ground water.•To reduce ground water contamination.•To supplement ground water supplies during lean season.•To prevent salinity.

Modern Techniques 1.Roof top Rain water harvesting2. Artificial ground water recharching3. Check Dams4. Embankment type water5. Underground tanks and Khadins(embankments)

Rain Water Harvesting in different Cities

1. In Amritsar (Punjab) - Golden Temple2. In JNU, Delhi campusthe water table has risen

from 0.8to 1.0 m after recharged through four check dams

3. In IIT, Delhi, water table raised by 3 to 4 m through roof for harvesting & recharge through two injection wells.

4. In Maharashtra, more than 7000 percolation tanks built after severe drought hit areas into green lands

5. In M.P more than 1000 check dams & 1050 tanks constructed in jhabua district.(It inc food production by 38% in last 5 years.6. In Jodhpur district (Rajasthan), Gramin vikas Samity motivated residents of 25 villages & built 2000 storage tanks. (Tanks are lined with alum & Lime, which keep stored water fresh for 4 months)

ADVANTAGES OF RAIN WATER HARVESTING1. Rise in water table by recharging the aquifers.2. Improves ground water quality by dilution.3. Reduces soil erosion by minimizing run-off

water.4. Mitigating the effects of drought &flood hazards.5. Reduction in use of energy for pumping water &

consequently the costs6. Assures sustainability of ground water

abstraction sources.