Assessment of groundwater recharge and its potential zone identification in groundwater-stressed Goghat-I block of Hugli District, West Bengal, India

摘要

This study is an attempt to demonstrate the actual groundwater recharge and groundwater recharge potential zones in semi-critical Goghat-I Block, using quantitative as well as geospatial techniques. Modelling groundwater recharge is necessary for optimum utilization of the resource, especially in a water-scarce region. According to the development of groundwater and long-term declining trend, Goghat-I is one of the semi-critical blocks of West Bengal. Water-level fluctuation method is applied to quantify the actual groundwater recharge, which shows significant micro-level variations in recharge rate. Inter-seasonal water-level fluctuation and specific yield are controlling the actual recharge rate. Increase in the post-monsoon water table from the pre-monsoon directly indicates the recharge. Identification of groundwater recharge potential zones (GWRPZ) is essential for water-scarce region, so that the policymakers can formulate effective plans to increase the recharge in favourable potential areas. GWRPZ have been identified through weighted overlay method, where the weight has been given through the analytical hierarchy process. Thematic layers of geology, geomorphology, slope, soil texture, land use land cover and pond frequency have been taken for identifying the recharge potential zones. These are the major controlling factors in this particular region behind the potential groundwater recharge zone. GWRPZ show that the major percentage of area is under the low potential zone. GWRPZ have been validated with groundwater recharge to observe the applicability of this approach. Favourable zones should be used for increasing the groundwater recharge with proper planning. This is necessary for the sustainability of the resource, especially in this region.