This is another term for polluted runoff and other sources of water pollution that are hard to pinpoint. The term "nonpoint source pollution" (NPS) comes from the federal Clean Water Act of 1987. There, it is used as a catch-all for all kinds of water pollution that are not well-defined discharges (point sources) from wastewater plants or industries.
NPS pollution, unlike pollution from industrial and sewage treatment plants, comes from many different sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into:
- Coastal Waters
- Underground Water Sources