In some cases such treatment is impossible or costprohibitive. It is far more effective and efficient to prevent contamination than to try to treat contaminated water. Reduced beneficial uses of contaminated surface water include losses to municipal, fishery, wildlife and recreational uses. Also, there are increased costs to end users if treatment is needed to attain adequate standards for a beneficial use. Erosion of land results in sedimentation in waterways.
Sediment carries adsorbed nutrients into water and displaces regular water flow.
Oxygen demand, either chemical or biochemical, is the amount of oxygen utilized as components are metabolized by water microbes. Use of oxygen by microbes reduces oxygen availability for fish and other organisms which can result in fish kills and undesirable characteristics of surface water. Addition of limiting nutrients results in excellent algae growth, death and decomposition, thereby deteriorating the water environment and potentially causing a water body to undergo irreversible eutrophication. The common name for the Water Pollution Control Act of 1972 is the Clean Water Act. Its key focus was to prevent degradation of our nation's surface waters by point source pollution, otherwise known as direct discharge into a waterway.