PERFORMANCE EVALUATION OF MODIFIED ADVECTION-DISPERSION EQUATION FOR MODELLING RIVER CONTAMINANT TRANSPORT

Modified 2-dimensional advection-dispersion equation has been used in this study to assess pollutant transport in streams. The Advection-Dispersion equation was modified to incorporate temperature. The dispersion term was expressed as a function of stream and air temperature and solved using Laplace transforms. It resulted in a concentration prediction models with temperature term. The model was evaluated using tracer data from experiment conducted to mimic the transport of contaminant in the New-Calabar River, Rivers State, Nigeria. During the evaluation, comparing the experimental data with the predicted concentration, the model predicts well the experimental concentration with a co-efficient of correlation of 0.920 and an average error of 0.01721. Test of significance (T-test) with 5% level of significance results showed that there is no significance difference between the measured value and the predicted values. Inclusion of temperature into the model reduced significantly the discrepancy between the observed and the predicted values and improved the predictive capacity of the model.