Estimates of Toxic Contaminant Mean Concentrations and Loads from Runoff Water Quality Data

The current modeling approaches for planning-level estimates of toxic pollutant loads in urban runoff focus on the loads from large scale areas for relatively long time intervals. These load estimates can be obtained by separating the calculations of runoff concentrations from the calculations of runoff volumes and using the mean event concentrations of limited runoff events to approximate the mean event concentrations of whole runoff events. Computations of mean concentrations and loads of toxic contaminants in urban runoff can be accomplished by means of a newly developed model referred to as the PMSQ model. Applications of the model are demonstrated on available runoff quality data.