Stormwater Management

Stormwater is the flow of water which results from, and occurs during and immediately following, a rainfall, snow- or ice- melt event. Stormwater management is any measure taken to permanently reduce or minimize the negative impacts of stormwater runoff quantity and quality.  Stormwater management is often implemented to mitigate the impacts of land development. Effective stormwater management depends on proper planning, design, installation, and continuing maintenance of management practices.

A Stormwater Management Permit is required for any of the following:

  • Any development after August 22, 2001 that results in the cumulative addition of 20,000 square feet of impervious surface to the site
  • Recording a subdivision plat
  • Recording a certified survey map intended for commercial or industrial use
  • Redeveloping more than 4,000 square feet of an existing commercial, industrial, institutional or multifamily-use site
  • Other land development activities that the local approval authority determines may significantly increase runoff, flooding, soil erosion, water pollution or property damage, or significantly impact a lake, stream, or wetland area

View Permit Applications and Additional Forms


Below is a map of the Urban Stormsewer Outfalls (greater than 36") and the land use for the greater Madison area.