Dynamics of the Groundwater Levels in Shallow Aquifers of WRC-1 Watershed, Chargarh River Basin, Central India

Abstract

Shallow unconfined aquifer in hard rock terrain generally have complicated and heterogeneous hydrogeological setup. Present study incorporates dynamics of the static groundwater levels in the Chargarh river basin, Central India, during pre-monsoon and post-monsoon season, with special reference to lithological variation. The geological formations exposed in the basin are Deccan basalt and alluvium. The average pre-monsoon and post-monsoon static water levels in the basalt formation are 12.21 mbgl to 6.14 mbgl respectively, with 6.07-meter seasonal water table fluctuation. On the other hand, average pre-monsoon and post-monsoon static water levels (SWL) in the alluvial formation are 16.84 mbgl to 4.64 mbgl respectively, with 12.20 m the water table fluctuation (WTF). The pre-monsoon SWL in alluvium is deeper as compared to the pre-monsoon SWL in basalt. Similarly, WTF in alluvium is higher than WTF in basalt. These observations are reversed to that of the general assumption, that the WTF in soft rock formations are lower as compared to WTF in hard rock terrain. This can be attributed to the excessive withdrawal of groundwater for orange cultivation and sporadic artificial recharge structures in the alluvial formation.