Basin discharge through HEC-HMS for estimating pollutant load of urbanized ungauged river sub basin

Abstract

The potable water quality demand increases with growing population, urbanization, and industrialization. The present study focuses on evaluating the pollutant load of Kalu Ela sub basin which is the secondly highest polluted sub basin of the Kelaniriver in Sri Lanka. The Hydrological Modeling System (HEC-HMS) was designed to simulate the precipitation-runoff process of five sub catchments of an ungauged river sub basin. Actual flow rate was recorded by calibration and validation of the Modeling system using area, soil type, land use pattern, ground cover and precipitation data of each sub catchments while thirteen water quality parameters were examined for identify most significant pollutants. This method may represent a valuable opportunity in the context of ungauged sub basin to estimate the pollutant loads. Chemical Oxygen Demand was recorded as the most significant pollutant in all sub catchments and there by pollutant load was estimated. The results were revealed that water quality monitoring mechanisms are essential to control the receiving pollutant loads from industries to river sub basins in order to protect potable water sources for future.