From 2014-2016, Herrera conducted water quality monitoring for Seattle Public Utilities (SPU) to evaluate the effectiveness of street sweeping on urban stormwater runoff. Herrera provided support for the experimental design, monitoring implementation, data analysis, and report review . Results were used to quantify the effect of street sweeping on stormwater quality by directly measuring runoff concentrations from roadways under swept and unswept conditions using a controlled paired-basin approach. Few street sweeping studies have used an experimental design this rigorous. Fine sediment was actually increased with sweeping, while coarse sediment and particulate copper was significantly decreased.
NPDES Phase I Municipal Stormwater Permit: Street Sweeping Water Quality Effectiveness Study Final Report
Reference: SPU. 2018. NPDES Phase I Municipal Stormwater Permit: Street Sweeping Water Quality Effectiveness Study Final Report. Seattle Public Utilities, Seattle, Washington.