The land that supplies water to the river system is called a <u>Watershed.</u>
Pollution from a single, identifiable source is called <u>point</u> source pollution.
Pollution that is difficult to link to a particular origin is called <u>non-point </u>source pollution.
A watershed is a land area that channels rainfall and snowmelt to creeks, streams, and rivers, and eventually to outflow points such as reservoirs, bays, and the ocean.
Point source pollution is a single identifiable source of air, water, thermal, noise or light pollution.
Non-point source pollution is a kind of pollution that occurs when runoff from rain and snowmelt carries pollutants into waterways such as rivers, streams, lakes, wetlands, and even groundwater.
To know more about different types of Pollution:
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