Abstract
This study describes the performance of five green infrastructure stormwater management (SWM) facilities. The five bioretention facilities were all located in parking lots and were selected for examination because of similar design characteristics, and availability of data on heavy metal concentrations in inflow and outflow water. Performance was determined by comparing influent to effluence concentrations for copper, lead and zinc relative to: (1) percent change, (2) total µg/L of reduction in concentrations, and (3) EPA standards of toxicity threshold data for these three metals.
Variability in heavy metal removal rate is considerable across the five sites. Results indicate: (1) copper concentrations were reduced in runoff water by 4-64 µg/L (43-97%), (2) lead concentrations were reduced by 0-41 µg/L (70-95%), and (3) zinc concentrations were reduced by 6.98-710 µg/L (65-95%). Last, qualitative comparisons were made between the 5 sites based on physical characteristics such as size, construction, and soil content.