Response of water harvesting structures on ground water recharge process in red soil of semi arid region of Andhra Pradesh.

Abstract

Ground water recharge estimation study is in progress since 2003-04 in red soil watershed of semi arid region, namely K.D.Pally watershed (920 ha) in Kambadur Mandal of Anantapur district (A.P.). In this region, the ground water is the only water resource meeting the various demands. Two number of percolation tanks and three check dams having a total capacity of 10.81 ham filling were selected to assess their effect on ground water recharge by monitoring the water table level in wells within the influence zone as well as irrigation quantity. Daily rainfall, evaporation and storage depth in structures are being measured to quantify the percolation. Well-irrigated cropping pattern data for each season was also monitored to compute the ground water extracted. Rainfall ~ runoff relationship, storm wise curve number, watershed storage and potential recharge were also developed. It is observed that CN is reduced and storage increased : which in turn increase in irrigated area.