Analysis of Groundwater Quality in Dhaka Division

Abstract

The primary reason that may be identified for significant deterioration in groundwater quality parameters is the rapid change in climate and temporal variability of water supply system. The main objective of this study is to identify the trend change according to time and the co relation between the parameters in 18 different locations of Dhaka division for 40 years’ time cycle. To characterize the water quality of the sites, Man Kendal test ,Modified Man Kendal, Sens Slope are used for trend analysis. Besides, spatio temporal variation of 15 groundwater quality (Ca,Mg,Na,pH,CO2,TDS,K,Cl,CO3,SO4,NO2,Fe,Si,F,HCO3)are determined by mapping in GIS. For establishing correlation between parameters Pearsons Correlation matrix has conducted. The individual hydro chemical characteristics of every stations is demonstrated by Piper Diagram. The results indicated the consequential increasing trend at almost 30% of the sites in all the parameters. Besides, the correlation matrix also provides a strong correlation between the Na & Cl , Mg & SO4 that causes salinity and total hardness. The hardness also identified from piper diagram as well. TDS (Total Dissolved Solid) and the increasing of HCO3 is also a great concern for the study areas. Finally, the groundwater quality in Dhaka division is investigated by whiskers plot,which showed that the groundwater quality of 43% stations are beyond the standard limit