Aliran permukaan pada lahan pertanian (farm field) membawa banyak polutan, diantaranya pestisida, pupuk, dan kotoran hewan, sebagaimana dalam Clean Water: An Introduction to Water Quality and Pollution Control (2003:47),
Stormwater runoff typically contains many pollutants. For example, runoff from roadways and parking lots often contains oil, gasoline, and other automobile fluids. Runoff from farm fields may include pesticides, fertilizers, and animal wastes.
 The rainwater that runs off is called stormwater runoff.