In order to obtain the detailed information necessary to develop design guidelines for the stormwater best management practices (BMPs) included in the Virginia Department of Transportation's Stormwater Management Manual, a field program was initiated in 1991 for testing the pollutant removal efficiency of selected BMPs. This report summarizes Phase II of this endeavor. A dry detention pond that drained a small, highly impervious area and a vegetated swale that received runoff from an urban highway were examined. Manual and automatic sampling techniques were used to monitor stormwater flowing into and out of the two facilities. Pollutant removal efficiencies were determined using a mass balance method. Pollutants measured were total suspended solids, chemical oxygen demand, total phosphorus, and zinc. The results suggest that, if properly designed, these types of facilities can be effective tools for removing stormwater pollution from highway runoff.

In order to obtain the necessary detailed design guidelines for storm water best management practices (BMPs) included in the Virginia Department of Transportation's storm water manual, a field program was initiated in 1991 for testing the pollutant removal efficiency of selected practices. A dry detention pond with a small, highly impervious drainage area and a vegetated swale draining runoff from an urban highway were selected for the study. Manual as well as automatic sampling methods were used to monitor storm water runoff into and out of the two facilities. Pollutant removal efficiencies were calculated by a mass balance method. Pollutants examined included total suspended solids, total phosphorus, and total zinc. Preliminary data showed that, if properly designed, these types of facilities can be an effective tool for removing storm water pollution from highway runoff.

At head of title: National Cooperative Highway Research Program.