What is "non-point source" pollution?

Non-point source pollution refers to pollution that comes from multiple, diffuse sources rather than from a specific, identifiable point, such as a pipe or a drainage outlet. This type of pollution is often a result of rainfall or snowmelt washing over land surfaces and carrying away pollutants into water bodies. Common contributors to non-point source pollution include agricultural runoff, urban stormwater, and sediment from construction sites.

Understanding this definition is crucial in stormwater management, as non-point source pollution can significantly affect the quality of water in rivers, lakes, and coastal areas without being easily traced back to a specific location. This makes the management and regulation of non-point source pollution particularly challenging compared to point source pollution, which can typically be controlled through permits and specific regulatory measures.