Recharging Dugwells and Abandoned Tubewells

Rain Water Harvesting is the call of the day due to the immense shortage of water with the growing population and the increasing number of apartments. Each Cochin apartment today stresses on the installation of the rain water harvesting system. The water thus saved can be used for personal purposes like drinking, washing, bathing etc. or for recharging the groundwater.

There are a number of wells which have gone dry or whose water levels have declined considerably in the alluvial and hard rock areas. Rooftop run-off can be directly used to recharge them. Drain pipes are used to divert the rainwater that is collected on the rooftop of the building to a settlement or filtration tank and from there into the recharge well i.e. borewell or dugwell. The casing or outer pipe of the tubewell used for charging should be preferably a slotted or perforated pipe so that greater surface area is available for the water to percolate. The recharging capacity of a borewell is increased by developing a borewell. Providing the well lining with openings at regular intervals increases the seepage of water through the sides of the dugwell which is used for recharging. To prevent mosquito breeding and entry of leaves and debris the dugwells should be covered. To maintain the intake capacity the bottom of recharge wells are desilted annually. The provision of elements like filter mesh at the entrance point of rooftop drains, settlement chamber and filter bed in the system can ensure the quality of water entering the recharge wells.