Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering

Committee Chair(s)

Ryan Dupont


Ryan Dupont


Joan McLean


Sarah Null


This study provides an evaluation of the performance of the WinSLAMM model in two cities of northern Utah, a region in which it has not been validated to date. Runoff volumes for a series of events from 2015 to 2017 were calculated for six study areas. These results were compared to model outputs to evaluate the prediction accuracy. The model performed poorly when default parameters where used, as expected. Thus, the calibration of runoff coefficient was done with local data. Total suspended solids (TSS), total phosphorus (TP) and total dissolved phosphorus (TDP) were also evaluated and calibrations were developed. The WinSLAMM model performed well for TSS prediction and TP and TDP estimations were calculated with the TP/TSS and TDP/TP ratios observed in the data for the Logan study areas.

Three scenarios of GI implementation were analyzed; the treatment of 10%, 50% and 100% of connected impervious surfaces. For the 10% case, treating streets produced the greatest TSS reduction, while treating roofs yielded the greatest volume reduction. For the 50% case, there was a great difference in TSS reduction with varying surfaces. Implementing GI for streets produced the largest TSS reduction, followed by parking lots and then by roofs.