Spring, 1990
Arroyo,
vol.
4,
no.
1,
pages
1-8,
8
pp.,
Water Resources Research Center,
Tucson, AZ,
Spring,
1990
![Arroyo Spring 1990](/sites/wrrc.arizona.edu/files/styles/az_natural/public/2022-08/arroyo_1990_v4_n1_w_Page_1.png?itok=IiD1UCyf)
Although many and varied, all sources of water pollution are classified as either point or nonpoint. Pollution comes from a point source if its origins are distinct and identifiable; hence, point source is also called an end-of-the-pipe source. Pollution from point sources can usually be quantified, often by direct measurement. Point sources can often be regulated effectively with federal and state permits.