Performance Evaluation of Regional Wet Detention Ponds and a Wetland for UrbanNonpoint Source Control

摘要

The pollutant removal efficiency of two regional wet detention ponds (Mall PondsA and B) and a regional pond-wetland system (Regency) were monitored over a 12-month period to identify watershed and/or design characteristics that may influence BMP performance. Watersheds with similar land use classifications and amounts of impervious surface often had very different pollutant characteristics. Annual pollutant removal efficiencies in Mall Pond A and B were similar to previously observed removal efficiencies in two nearby ponds (Davis and Piedmont Ponds) and to other literature reports. Total suspended solids (TSS), total phosphorous (TP), and total nitrogen (TN) removal was similar in Pond A and B relatively constant throughout the year. However, in Pond A, dissolved nutrient removal efficiencies were more variable with higher removals observed during the growing season. In Pond B, dissolved nutrient removal was somewhat lower and more uniform than in Pond A, presumably due to the lower level of biological activity in this pond.