Model development for stream quality management

Abstract

This study is aimed at finding the level of wastewater treatment at two sites that would achieve the desired concentrations at a minimum total cost for a river that received wastewater effluent from some other two point sources located at two sites. Pollutant concentrations and stream flow in the stream at selected reaches were obtained. Linear programming model was developed incorporating waste transfer coefficients. The model was applied at Nworie River in Imo State, Nigeria. The model solution was obtained using graphical method and the results revealed that 80% treatment efficiencies met the stream standards for the design stream flow and waste load condition at a total minimum cost. The study shows that least-cost waste removal efficiencies could be determined without prior knowledge of the cost functions.

Keywords: Linear programming, wastewater treatment, model, stream