Storm water runoff is any water that is not soaked into the ground after a rain storm. Consequently, stormwater runoff can pick up pollutants while flowing into local streams and rivers. The Storm Water Management Program (SWMP), launched in 2003, is ODOT's inter-agency effort to control pollutants in storm water discharge. By unifying a cross section of ODOT programs, such as training, planning, maintenance, construction and facilities management with a common focus on water quality issues, ODOT complies with the Clean Water Act requirements administered by the Ohio EPA while reducing pollutants from Ohio's storm sewer system.

ODOT created the SWMP in response to being regulated as a Municipal Separate Storm Sewer System (MS4). The MS4 designation invokes federal legislation that mandates all municipalities reduce the quantity of pollutants from stormwater runoff.

ODOT administers the SWMP through the following activities and projects:

The MS4 Storm Water Outfall Inventory identifies and maps storm water outfalls -- every point where a conveyance of ODOT's storm water system discharges into streams, rivers, lakes and wetlands

The SWMP Plan and Annual Report on National Pollutant Discharge Elimination System (NPDES) permit program activities documents ODOT's SWMP activities completed in 2010 and the proposed activities for 2011.

The Best Management Practicies (BMPs) described in the Annual Report are commen sense approaches to reducing storm water pollution with the framework of ODOT's organization and mission.