More on Nonpoint Source Pollution
Usually, if pollutants come from one source into that water body, (such as a factory disposal) it is called a point source pollution. For example, during meat processing in a slaughterhouse, high volumes of water may be used, making it a significant point source pollution to local ecosystems and communities.
If the pollution comes from many sources, it is called nonpoint-source pollution.
Pollution can also affect only one area in which the pollution happened. But in many cases, especially for flowing water, the contamination spreads to many other places. This is called transboundary pollution.
In many of the states in the USA, there are reports that nonpoint source pollution is the leading remaining cause of water quality problems. These reports may not be unique to the USA alone, and very likely a similar scenario would be so in many other developed countries.
Nonpoint source pollution can include:
Excess of fertilizers, herbicides, insecticides and chemical application from agricultural lands and residential areas
Oil, grease and toxic substances from energy plants and municipal runoff.
Debris and sediment from construction sites, farm and forest lands.
Acid drainage from abandoned mines.
Waste, bacteria and nutrients from animals, waste from pets as well asand faulty septic tanks.
Chemical / particle deposits from the atmosphere and hydromodification.