ASSESSMENT OF SPATIAL GROUNDWATER LEVEL VARIATIONS USING GEOSTATISTICS AND GIS IN HARINGHATA BLOCK, NADIA DISTRICT, WEST BENGAL

Alivia Chowdhury

Abstract: The use of groundwater has increased manifolds in the recent past due to increased water demands owing to the accelerated growth of population and industrialization. A quantitative groundwater assessment study was carried out in Haringhata Block, Nadia district, West Bengal for the sustainable utilization of the vulnerable groundwater resource of the area. In the present study, the spatial variation of groundwater levels was investigated by geostatistical modeling technique in GIS environment. Premonsoon and post-monsoon groundwater depth data of 16 observation locations for 8 year period (2004 to 2011) were considered for the present study. Four geostatistical models namely, linear, circular, Gaussian, and exponential, were selected to understand the spatial variability of the pre- and post-monsoon groundwater depth data in the study area. Finally, the best-fit geostatistical models for pre- and post-monsoon groundwater depth were chosen by comparing the observed values and the values predicted by empirical semi-variogram models. The best-fit geostatistical models were then used to generate spatial maps on pre- and post-monsoon groundwater depth using QGIS 1.2 software. Out of the four semi-variogram models, Spherical model and Gaussian model were found to be the best-fit geostatistical model for pre-monsoon and post-monsoon groundwater depth, respectively for the study area. The results obtained, thus, justify the effectiveness of using geostatistic techniques in investigating the spatial variations of groundwater depths in the study area. This study is helpful in efficient and sustainable utilization of groundwater resources in the block.

Keywords: Geostatistics, Groundwater depth, Semi-variogram, Ordinary kriging.

DOI: https://doi.org/10.15623/ijret.2016.0505050