Rain water harvesting

Rainwater harvesting is the accumulation and storing of rainwater for reuse before it reaches the aquifer. It has been used to provide drinking water, water for livestock, water for irrigation, as well as other typical uses. Rainwater collected from the roofs of houses and local institutions can make an important contribution to the availability of drinking water.

It can supplement the subsoil water level and increase urban greenery. Water collected from the ground, sometimes from areas that are especially prepared for this purpose, is called Stormwater harvesting. In some cases, rainwater may be the only available or economical water source. Overflow from rainwater harvesting tank systems can be used to refill aquifers in a process called groundwater recharge. The basic purpose of artificial recharge of ground water is to restore supplies from aquifers depleted due to excessive ground water development.

The artificial recharge to ground water aims at augmentation of ground water reservoir by modifying the natural movement of surface water utilizing suitable civil construction techniques. Artificial recharge techniques normally address to following issues.

1. To enhance the sustainable yield in areas where over-development has depleted the aquifer.
2. Conservation and storage of excess surface water for future requirements, since these
   requirements often change within a season or a period.
3. To improve the quality of existing ground water through dilution.
4. To remove bacteriological and other impurities from sewage and waste water so that water is suitable for re-use.