Stormwater quality prediction utilizing load-runoff relationships
Harned, Douglas Alan
Bedient, Philip B.
Master of Science
Analyses of available storm water hydrologic and water quality data for several Houston area watersheds yielded direct linear relationships between pollutant mass loading rates and cumulative storm runoff volume. These relationships were then used to rank the watersheds on a pollutant load per unit runoff basis, and to calculate total annual pollutant loads for each area. Further, a plot of dimensionless cumulative flow versus the dimensionless cumulative flux provides a quantifiable means to evaluate the first flush, allowing comparison of this effect between watersheds. Finally, the developed load-runoff relationships provide the basis for a simple, yet effective method of predicting pollutant mass flows for individual or sequential storm events. An application of the water quality methodology to a previously unmonitored watershed provides a step-by-step outline and illustration of the proposed procedure.