Identification of Water Quality in Wet and Intermediate Zones in Selected, Sri Lanka: An Analytical Review

This study is based on the analysis of drinking water parameters in selected wet and intermediate zones of Sri Lanka. Unsafe drinking water is one of the main concerns in developing countries. In Sri Lanka, the drinking water quality is a major concern in many places. A series of studies have been conducted in intensive agricultural production areas, namely, Jaffna, Vavuniya, Anuradhapura, Kurunagala and Hambantota. This represents a longitudinal section of Sri Lanka, and the study was done to understand the groundwater quality over the years of 2004 to 2009. Water from selected areas were sampled throughout the villages of this area mostly from open wells and tube wells. The samples were analysed for their chemical quality in order to identify water quality as compared with the Sri Lankan Drinking water standard. For this study, Sodium (Na+), Calcium (Ca2+), Magnesium (Mg2+), Chloride (Clˉ), Sulphate (SO42ˉ), and Nitrate (NO3ˉ) were analysed. Accordingly, in the Dry Zone, the concentration of the Ca, Mg and Cl are higher than in the Wet Zones. Indeed, some sampling wells in the Dry Zones have extreme concentration of Ca (more than 1000 mg/L) and this is a major threat to the consumers for drinking purposes. In total, of 103 wells, 6 percent of the sampling wells were identified as contaminated, whereas in total, of 96 wells in the Dry Zone, 64 percent of the sampling wells were found to be contaminated due to chemical concentration. We found that rural areas are facing agrochemical-leaching problems into the groundwater, whereas urban areas are facing industrial and biological materials seeping into the ground and surface water bodies.