Stormwater Filter Verification at the Madison Gas and Electric Parking Lot
Project Number: BQY27
Project Chief: Judy Horwatich
Project Topics: NPDES
Cooperators: Wisconsin Department of Transportation; MG&E; WDNR
Period of Project: April 2005–December 2007
Samples were collected during 15 of the 30 storms planned to be sampled. Cameras were installed at the site to verify bypass occurrences.
The Wisconsin Department of Transportation (WisDOT) is mandated by the National Pollutant Discharge Elimination System permits and through Federal and State laws to improve water quality from our systems draining into the waters of the State.
Per the Cooperative Agreement between the Wisconsin Department of Natural Resources (WDNR) and WisDOT (November 2002), Trans401 (December 2002), and NR 216 (September 2002), the Department is required to provide a stormwater management program that reduces total auspended solid (TSS) loading. The statutes dictate that the Department evaluate and assess best-management practices (BMPs) on an annual basis.
The objectives of this project were to (1) determine the effectiveness of a stormwater filter management from a parking lot; (2) compare the measured removal efficiencies with manufacturers’ estimates; (3) characterize the variability in freeway runoff quality; (4) characterize pollutant loading in parking-lot runoff; and (5) determine the practical application of the treatment devices (for example, installation, operation and maintenance costs).
To evaluate the treatment efficiency of a stormwater-filtration device (SFD) for potential use at Wisconsin Department of Transportation (WisDOT) park-and-ride facilities, a SFD was installed at an employee parking lot in downtown Madison, Wisconsin. Samples from the inlet and outlet were analyzed for 33 organic and inorganic constituents, including 18 polycyclic aromatic hydrocarbons (PAHs), and for physical properties, including PSD. Water-quality samples were collected for 51 runoff events from November 2005 to August 2007. Samples from all runoff events were analyzed for concentrations of suspended sediment (SS). Samples from 31 runoff events were analyzed for 15 constituents, samples from 15 runoff events were analyzed for PAHs, and samples from 36 events were analyzed for PSD. The treatment efficiency of the SFD was calculated using the summation of loads (SOL) and the efficiency ratio methods.
Publications and Reports
Horwatich, J.A., and Bannerman, R.T., 2010, Parking lot runoff quality and treatment efficiency of a stormwater-filtration device, Madison, Wisconsin, 2005–07: U.S. Geological Survey Scientific Investigations Report 2009–5196, 50 p.