Assessment of Groundwater Potential Utilizing Gis and Estimation of Groundwater Recharge by Swat Model

Abstract

In present situation groundwater is an essential natural resource for domestic use, industrial purpose and agricultural purpose. Due to less rainfall in monsoon it should be used in optimum manner and groundwater recharge places should be identified. Due urbanization and industrialization vegetation cover of the land decreases there will be less infiltration it is a key risk for this valuable resource. For proper management of groundwater it should be used in optimal manner. In present case an attempt is made to demarcate groundwater zones in Suryanagar watershed which comes under kaveri river basin having Latitude of 12º-47′-32″-N & Longitude of 77º-41′-59″-E, Bangalore having an area of 172.42km2 and also to identify recharge zones of the study area. Morphometric analysis of watershed is carried out using GIS and parameters such as Linear, Areal and Relief aspects have been determined. From the drainage map it can be seen that the area is having dendritic drainage pattern. The drainage’s Densities obtained of water shed obtained is 1.48km/Sq.km.Further work is carried to find groundwater potential zones and groundwater recharge zones of watershed using GIS (Geographical Information System). Different thematic have been prepared such as Geomorphology, Lithology, Slope, Rainfall, Land use and soil. Weighted overlay analysis have been made and each thematic map is given weightage based on the influence of groundwater occurrence. Five types of groundwater zones have been identified and demarcated such as poorer, just moderately to very moderate, good & very very good. Recharge estimation is carried out using SWAT and recharge varies from 170mm to 500mm and it is compared with groundwater potential map. The comparison shows that recharge is maximum where groundwater potential is maximum and vice-versa.