Ecology, Environment and Conservation Paper

IDENTIFICATION OF SUITABLE SITES FOR RAINWATER HARVESTING BY USING GEOSPATIAL TECHNIQUES IN HALAYAPURA MICRO-WATERSHED OF TUMKUR DISTRICT

N. Manoj, K.S. Rajashekarappa, K. Devaraja and M.D. Majeed Pasha

Abstract

Geospatial technique were used for land and water management action plan for Halayapura micro-watershed in Tumkur district of Karnataka. Arc GIS software was used in evaluation of morphological characteristics in micro-watershed. The main objective of this study was to define a general method for selecting suitable. RWH sites in Halayapura micro watershed. Rainwater which is harvested using structures of varying types and sizes was used for either supplemental irrigation or recharging open-wells. In many cases, the farm level rainwater harvesting structures were highly effective for rain fed farming and had a multiplier effect on farm income. The use of farm ponds in Halayapura, for example, resulted in a significant increase in farm productivity (12–72%), cropping intensity and consequently farm income. The recharge factor found is 7% and utilizable groundwater is 41.7 mm (70% of 59.6 mm recharge estimated). This means the total available water resource combining the soil moisture store and utilizable runoff plus recharge is 256.0 mm. Currently about 19.4% of the utilizable runoff is being used and 9% of runoff excess is promoting by harvesting and conservation structures.