Assessment of Water Quality in Different Inlet and Outlet Canals of Kurunegala Lake, Sri Lanka

Abstract

Kurunegala Lake is one of the major drinking water supplying tanks in Kurunegala, Sri Lanka. Water quality assessment is vital for the sustainable management of drinking water resources. This study evaluated the temporal variability of water quality in different inlets and outlet canals of Kurunegala Lake. Three major inlets and one outlet canals connected to Kurunegala were identified, and one sampling location was selected from each of these canals. Water samples data were collected from each selected location in a one-month interval for three years. Water quality parameters were determined in each water sample, such as pH, Electrical Conductivity (EC), Dissolved Oxygen Level (DO), Total Dissolved Solids (TDS), Nitrate-nitrogen (NO3–N), and Available Phosphorus (Av.P) concentrations. This study showed that pH, DO, NO3–N, and Av.P of some of the water samples tested were within permissible levels according to WHO & SLS drinking water standards, CEA act. The inlet and outlet canals showed a temporal and spatial variation in water quality parameters during the study period. The results conclude that there is an impact of surrounding land use on water pollution in inlet water canals connected to Kurunegala Lake. Therefore, a pollution management plan is required to prevent further pollution by conducting future research.