The City of Lake Oswego operates a surface water management utility that includes ”all natural and man-made facilities utilized by the Surface Water Utility to regulate the quantity and quality of surface water, including drainage easements, culverts, storm drains, catch basins, stream corridors, rivers, ponds, wetlands and impoundments.” The goal of the program is to reduce pollutants to the maximum extent practicable (MEP).
The City of Lake Oswego’s stormwater system is not connected to the City’s wastewater system. As a result, stormwater enters receiving waters untreated. Stormwater and other “nonpoint source discharges” (NPS) are regulated by the 1972 Federal Clean Water Act through the National Pollutant Discharge Elimination System (NPDES) permit program. The State of Oregon Department of Environmental Quality administers this permit program in Oregon for the United States Environmental Protection Agency (USEPA).
The Federal Clean Water Act and the State of Oregon mandate that the City of Lake Oswego be issued a NPDES Phase I permit. The City of Lake Oswego shares a permit with twelve other jurisdictions including Clackamas County, City of Gladstone, City of Happy Valley, City of Johnson City, City of Milwaukee, City of Oregon City, City of Rivergrove, City of West Linn, City of Wilsonville, Oak Lodge Sanitary District, Clackamas County Sanitary District #1 and the Surface Water Management Agency of Clackamas County.