Non-point source pollution
- Slovak term: Slovenský termín
- A pollution input that cannot be related to a single outlet (UNEP et al. 1997)
Explanation
Non-point sources arise mainly from agriculture, but urban road run-off, effluents from contaminated land and effluents from storm sewage overflows are also known to contribute to the problem. In some countries the latter would be classified as point sources although they are difficult to control.
It is more difficult to control non-point source pollution than defined discharges. Even though stringent controls may be placed on industrial and municipal sewage discharges, environmental water quality may not improve to the extent expected. This may be due to diffuse pollution caused by agriculture or by urban run-off. The first problem lies in the identification of sources (UNEP et al. 1997).
Example
Classes of non-point source pollution (highlighted categories refer to agricultural activities) (Source: International Joint Commission, 1974, and other sources)FAO (1995) Control of water pollution from agriculture
References
- UNEP, Water Supply & Sanitation Collaborative Council and WHO (1997) Water pollution control: a guide to the use of water quality management principles
- FAO (1995) Control of water pollution from agriculture