Stormwater Management is the process of controlling the runoff that comes primarily from impervious surfaces like parking lots, driveways and roof tops. In Roanoke County, the stormwater system is separate from the sanitary sewer system. Stormwater flows directly from streets and gutters into our streams and rivers, often with little or no treatment. Stormwater can also transport pollutants that collect on these hard surfaces such as motor oil, household cleaners, and other materials which may negatively impact water quality.