Construction of Recharge Well Structures

Background

Owing to the complex geology of the district, the rate of infiltration into the ground is not as per expectations, that is, it is not uniform. In spite of constructing several water harvesting structures, ground water was rapidly declining. The situation demanded recharging of freshwater zones in declining water table areas with artificial means to maintain the groundwater table at optimum levels. In order to resolve the problem, the district administration after examining different options, has decided to take up artificial recharging of the aquifers directly by drilling a borewell.

Intervention

Recharge borewell (invert well) fills water into an aquifer using gravity, based on the transmissivity of the aquifer. By implementing the above concept, 16 recharge well structures have been constructed in Naravakati and Kothamadhavam villages of Vontimmita Mandal and are yielding good results in ground water improvement. In order to build a recharge well, potential aquifers are first identified. Drilling of recharge borewell is done and a casing pipe is inserted to required depth. A recharge pit is constructed around the borewell with filter media.

Impact

The normal rate of infiltration is 60 litres per hour, but with construction of recharge well structures it is 31,000 litres per hour. With an investment of `35-40 lakhs for construction of 16 recharge wells, the expected returns are `138 lakhs per annum.

Source : Aspiratonal Districts for WEB