Study on the quality of alluvial groundwater for irrigation and drinking purposes in an agricultural belt Dakshin Dinajpur West Bengal India

Abstract

Alluvial terrains are favourable for intense agricultural activities. Long term cultivation of highly water-demanding crops using inorganic fertilizer in alluvial terrain has led to degradation of groundwater quality as well as groundwater depletion. This is very common scenario globally. The groundwater quality in the region which is dependent economically on agriculture determines the socio-economic aspects of the community. Using poor quality of groundwater for irrigation purposes can cause low crop quality, yield and its consumption may have severe effect on human health. Dakshin Dinajpur is an important agricultural belt of West Bengal. The groundwater in the region occurs in clay and sand layers and the region is made up of Older Alluvium Barind Tract and Recent Younger Alluvium. In the district, agricultural practices are done around the year with the help of irrigation in various scale. Shallow (low-duty) and deep (heavy-duty) tube wells are mainly used for groundwater withdrawal for irrigation, domestic and drinking purposes. The present study has been carried out in the district of Dakshin Dinajpur in West Bengal with the aims to understand the trend of seasonal fluctuation of depth to water level (DTW) in the district, to delineate groundwater potential zones (GWPZ), to determine the different hydrochemical processes operating in the region, to assess the groundwater quality which is being utilized for drinking and irrigation purposes and finally to propose probable measures to address the degrading scenario of groundwater quality and related aspects. newlineDepth to water level (DTW) was measured from 69 locations for three consecutive years in three different seasons, pre monsoon, post monsoon and lean. Using remote sensing (RS) data and Arc GIS 10.0 different thematic maps are prepared based on Analytic Hierarchy Process (AHP) to estimate the groundwater potential zones (GWPZ). The physiochemical data pH, TDS (Total Dissolved Solids) and EC (Electric Conductivity) have been measured in the fields