What is a "Non-Point Source" of pollution?

A "Non-Point Source" of pollution refers to pollution that does not originate from a single, identifiable source but rather comes from multiple sources that are often diffuse. This type of pollution is typically associated with runoff from urban areas, agricultural lands, and other widespread land uses where contaminants can wash off into water bodies during rainfall or snowmelt. The myriad of sources makes it challenging to pinpoint the exact origin of the pollution, which complicates management and regulatory efforts.

For example, urban runoff may carry pollutants such as oils, heavy metals, and sediments from streets and parking lots into nearby rivers and lakes. Similarly, agricultural practices may contribute to non-point source pollution through fertilizers and pesticides that are spread over large areas and washed away by rain. These diffuse sources collectively lead to significant environmental impacts on water quality.

The context of the other options helps reinforce why they don't align with the definition of non-point source pollution. Pollution from a single, identifiable source is termed "point source" pollution, and that does not fit the non-point source classification. Industrial discharges are also point sources where pollutants are released in specific locations, which makes tracking the pollution straightforward. While agricultural practices can contribute to non-point source pollution, they can also be managed and classified differently based