As stated on the EPA National Pollutant Discharge Elimination system (NPDES) website, stormwater discharges are generated by:
- runoff from land and impervious areas
- such as paved streets,
- parking lots, and
- building rooftops during rainfall and snow events
that often contain pollutants in quantities that could adversely affect water quality. The primary method to control stormwater discharges is through the use of Best Management Practices (BMP).
Stormwater pollution from Point sources and Nonpoint sources is a challenging water quality problem. Unlike pollution from industry or sewage treatment facilities, which is caused by a discrete number of sources, stormwater pollution is caused by the daily activities of people everywhere. Rainwater and snowmelt run off:
- Lawns, farms, construction and industrial sites; and picks up
- fertilizers, dirt, pesticides, oil and grease, and many other pollutants on the way to our rivers, lakes, and coastal waters.