Groundwater Quality Assessment for Bursa—A Multi-catchment Region

This study represents a comprehensive analysis of the groundwater quality in a data poor catchment located in Bursa region of Turkey. The dataset includes three years of groundwater monitoring data from 12 observations wells. The data were recorded between 2015 and 2018 at a biannual temporal scale. The spatiotemporal variations in groundwater indices were investigated using an advanced analytical method to determine the role of anthropogenic activities on the quality of groundwater for irrigation and drinking purposes. The primary properties of the groundwater quality are determined using sodium percentage, sodium absorption ratio (SAR), magnesium hardness (MH), permeability index (PI), residual sodium bicarbonate (RSBC), soluble sodium percentage (SSP), Kelly’s ratio (KR), base exchange index (BEI), meteoric genesis index (MGI), and the water quality index (WQI). Following the primary analysis of groundwater characteristics, a holistic data analysis is proposed using Piper-, Durov-, and Wilcox-diagrams to provide a detailed overview of the groundwater quality in the region. The results indicate that, in general, groundwater quality in the region is suitable for irrigation purposes. However, it was also observed that there are discrepancies among the samples, indicating variations in the groundwater quality within the study area. The data analyses revealed that the groundwater in the Bursa region is predominantly of the alkaline type, while the prevailing anions and cations in most of the samples are HCO3− and Ca2+. These findings suggest a correlation with rock dissolution and geomorphological processes in the study region. The disturbances in EC and variance also indicate possible pollution in the groundwater that could be attributed to a combination of anthropogenic activities and climate change.