Assimilative capacity and water quality modeling of rivers: a review

Abstract The rivers rejuvenate themselves by traveling over a distance, thereby they assimilate the pollution load and cause their own self-cleansing, also termed ‘Self-purification capacity’. To ascertain such assimilative capacity of river system, various water quality models (WQMs) were studied. Out numerous WQMs, six including QUAL2Kw, WASP, SWAT, SIMCAT, MIKE-11, CE-QUAL-W2 selected studied on basis development, characteristics, capabilities strengths, model input, governing equations, application, assumptions limitations. A comparison based study showing input variables data, limitations, specific characteristics has been carried out tabulated. While selection is problem for which decision-making to be done. Of all models, QUAL2Kw WASP have found advantageous rest. For complex single may not work in cases, combination tried. finally must calibrated so as minimum errors maximum accuracy.