Analysis of groundwater quality in Dhaka division, Bangladesh

![CDATA[Preserving groundwater quality is the key challenge for Bangladesh in recent times. 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 sources. Soil characteristics are also responsible for groundwater quality transition of the particular area. Thus, a thorough understanding of numerous hydrochemical processes is required to conserve groundwater quality. This study aims to investigate the trends of groundwater quality change on a broader scale to gain a better understanding of district groundwater quality variation over time. This study correlates the 15 quality parameters of every individual location (18 stations) across the Dhaka division over a 35-year time cycle. Mann-Kendal test, Modified Mann-Kendal, and Sens Slope have been conducted to detect the diversity of the trend and the slope of the trend line. Piper Diagram was used to identify the individual hydrochemical characteristics of every station. Besides, the spatial-temporal variation of 15 groundwater quality is determined by mapping using GIS. The results indicated a significant decreasing trend in pH, Iron, sodium & magnesium of all the stations. However, the other parameters show an increasing trend which is a great concern to maintain the groundwater quality. On the other hand, the correlation matrix provides a strong correlation between Na+ & Cl-, Mg+2, and SO4 -2 which causes salinity and total hardness in most of the stations. Piper Diagram also illustrates that Madaripur Sadar groundwater has severe salinity problems. The findings of this study help researchers understand the current situation of groundwater quality and help them to take the necessary measures to preserve it.]]