Jain, S. K.Kumar, Avinash2018-01-292018-01-292015http://krishikosh.egranth.ac.in/handle/1/5810039933Estimation of groundwater is an effective tool for proper planned and optimal utilization of water resources in the context of future requirement. Our main purpose for the estimation of groundwater in Patna and Gaya district is to make a complete assessment of groundwater resources and produce information that can be incorporated for future requirement. The study was undertaken based on the recommendation of groundwater estimation committee, 1997 (GEC-97). Methodology used the estimation of annual groundwater recharge from rainfall and other sources including irrigation, water bodies and artificial recharge, determination of present status of groundwater utilization and categorization of assessment units based on the level of groundwater utilization and long- term water level trend. Water level fluctuation techniques and empirical norms were used for recharge estimation. The data collected for investigation were water table fluctuation, rainfall, cropping pattern, number of groundwater structures, geographical area, groundwater draft, ponds area etc. The study reveals that for Patna and Gaya district the total annual groundwater recharge is 123796.4 ha-m and 107866 ha-m, the net annual groundwater draft for all uses is 57933.2 ha-m and 54390.6 ha-m, the net groundwater available for future irrigation development is 59673.2 ha-m and 48082.1 ha-m respectively. The stage of groundwater development is 49.3% for Patna district and 53%for Gaya district which fall in safe categories for both districts. The surplus of groundwater available for future agriculture is 12583.7 ha-m and 7173 ha-m and the additional energy requirement for abstraction of surplus of groundwater available for future agriculture is 4.80 × 106 KWh and 1.55 × 106 KWh for Patna and Gaya district respectively.ennullThesis