Nonpoint sources of water pollution are defined as land and air use activities that contribute to pollution of ground and/or surface water as a result of runoff, of nonpoint source pollution leachate from septic tanks seepage, or percolation. Major sources are agriculture runoff, urban runoff, and landfills, runoff from forestry and mining operations, and hydrologic modifications. Nonpoint sources of water pollution are responsible for approximately three-fourths of the water quality problems in Tennessee.
The Clean water Act of 1987 (Act) requires states to begin addressing the problem of nonpoint sources of water pollution.
Rollins, Sharon, "Nonpoint Sources of Water Pollution" (1988). MTAS Publications: Technical Bulletins.