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Stormwater Pollution Prevention Program (SWPPP)

Lakes, rivers, streams and wetlands are among the most important natural resources for Minnesotans and we all have an interest in ensuring their quality for future generations. But when rain falls on impervious surfaces such as paved streets, parking lots and rooftops, it can collect materials that pollute our water resources. Polluted runoff containing pesticides, sediment, nutrients, oil, chemicals, and litter is often transported through storm sewer systems to our lakes, rivers, streams and wetlands.

A 1987 amendment to the federal Clean Water Act required implementation of a two-phase national program to address storm water runoff and its associated pollutants. Phase I of the program focused on construction sites larger than 5 acres, specific categories of industrial activity and major metropolitan cities. In Minnesota, the cities affected by Phase I of the storm water program were Minneapolis and St. Paul.

Phase II expanded the permit requirements to include construction sites greater than 1 acre and smaller municipalities. As a result, the City of Woodbury, along with many other communities in Minnesota, was required to obtain a Phase II National Pollutant Discharge Elimination System (NPDES) permit from the Minnesota Pollution Control Agency (MPCA) in March 2003. The permit requires cities to address how they will improve water quality by reducing or eliminating pollutants from storm water runoff before it reaches the city's surface waters.

The MPCA reissued the NPDES Phase II permit in March 2006, requiring municipalities to submit a revised application and SWPPP by June 1, 2006. These documents guide the city's actions for compliance with the permit. The city must submit a new application and supporting materials every five years to the MPCA.

The city is required to submit annual reports to the MPCA on progress related to the NPDES permit. Annual reports are available upon request. To contact city staff about the Storm Water Pollution Prevention Program, send an email to or call (651) 714-3538.

To find out how you can help improve water quality, visit the Household Tips page.

For more information on surface water resources and stormwater management visit: