Stormwater Management is the process of controlling the stormwater runoff that comes primarily from impervious surfaces like parking lots, driveways, and rooftops. Rural areas are typically comprised of pervious areas, such as farmland, pastures, and woodlands. These areas absorb and infiltrate the rainfall and generate a small volume of runoff. Developed urban areas contain a higher percentage of impervious surfaces, such as pavement and rooftops. The quantity of runoff from these areas quickly overwhelms natural channels and streams causing channel erosion, localized flooding, and property damage.
Stormwater can transport pollutants, such as motor oil and household cleaners, from these impervious surfaces. This water flows directly from the streets into our creeks and rivers with little or no treatment. In the City of Marysville, storm sewers are separate from the sanitary sewer system.