Application of Qual2e Model for River Water Quality Modelling

Abstract

QUAL2E is modeling software which simulates up to 15 water quality parameters in branching stream system. The model uses mathematical equations like finite-difference solution of the adjective- dispersive mass transport and reaction equations. The program computes a series of steady- state water surface profiles and simulates changes in flow conditions along the stream. The model is applicable only to dendritic streams that are well mixed and it assumes that the major transport mechanism, advection and dispersion are significant only along the main direction of flow of the stream. QUAL2E can operate as either a steady state or a dynamic model and it simulates dynamic dial heat budget and water quality kinetics for a one dimensional and steady flow system. QUAL2E program performs dissolved oxygen balance by including source and sink terms in mass balance equation and is used to quantify the non point sources loading rate, determine the pollutants, calculate the phosphorus and estimate the natural conditions. It accommodates four types of hydraulic and mass load functions in addition to local climate factors: headwater-inputs, point sources, inflow/outflow and downstream boundary conditions.