STUDIES OF GROUNDWATER FLOW AND ARSENIC CONTAMINATION IN PARTS OF YAMUNA SUB-BASIN, WEST BENGAL

Abstract

The management of the groundwater resources largely depends on their proper assessment and development. Yamuna sub-basin which consists part of Nadia and North 24 parganas district of West Bengal has been taken up for present study. Groundwater is the major source of water supply for irrigation as well as for drinking purpose in that area. The study area is situated between 22° 49' and 23° 03' north latitude of 88°24' and 88° 51' east longitude. It covers an area of 650 sq km. The river Hooghly flows along the western boundary and the river Ichamati flows along the eastern boundary of Yamuna sub-basin. The Yamuna sub-basin is a part of the upper Ganga-Brahmaputra Delta. Some part of the Yamuna sub-basin (Habra-I and Habra-II blocks of North 24 parganas district) was categorized `Grey' or `Semi-critical'. So that area need very cautious approach. In the present study an attempt is made to calibrate a groundwater flow model to analyse the ground water flow. In the present study a finite difference numerical flow model (MODFLOW) is used for comprehensive analysis of groundwater flow in the study area. The future water table trnds predicted with reduction of abstraction rate. The model can be used as tool for decision making by administrators for future groundwater development. Further, it has been reported that the Yamuna sub-basin is under the grip of arsenic pollution. In the present study, an attempt also made to understand the specific processes for release of arsenic in ground water and possible reasons of arsenicf pollution, an integrated evaluation of hydrogeology and hydrochemistry is carried out and an attempt has been made in this direction by processing the available data.. The groundwater domain of Yamuna sub-basin of West Bengal thus has been chosen as the study area.