Enviro 6.2

Water pollution

the addition of any substance to a body of water that might degrade its quality

Point source pollution

pollution from wastewater treatment plants or industrial sites, such as that from discharge pipes or smokestacks.

Effluent

wastewater discharged into the environment

Nonpoint source pollution

runoff that enters the water from overland flow

Storm-water runoff

water from precipitation that flows over the surface of the land

Dissolved oxygen (DO)

the amount of oxygen in the water

Hypoxia

a situation in which a body of water contains inadequate levels of oxygen, compromising the health of many aquatic organisms

Eutrophication

a process by which excess nutrients in aquatic ecosystems feed biological productivity, ultimately lowering the oxygen content in the water

Watershed

the land area surrounding a body of water over which water such as rain can flow and potentially enter that body of water

Chemical assessment

Chemical parameters of water quality such as pH and dissolved oxygen (DO) content are monitored to see if these values are within acceptable limits for the organisms who live there.

Physical assessment

Physical parameters that are assessed include the water’s turbidity (cloudiness) and temperature (higher temperatures mean lower DO levels).

Biological assessment

the process of sampling an area to see what lives there as a tool to determine how healthy the area is

Benthic macroinvertebrates

easy-to-see (not microscopic) arthropods such as insects that live on the stream bottom

Clean Water Act (CWA)

U.S. federal legislation that regulates the release of point source pollution into surface waters and sets water quality standards for those waters. It also supports best management practices to reduce nonpoint source pollution

Performance standards

the levels of pollutants allowed to be present in the environment or released over a certain time period

Watershed management

management of what goes on in an area around streams and rivers

Total maximum daily loads (TMDLs)

he maximum amount of a pollutant allowed to enter a water body so that the water body will meet water quality standards

Riparian areas

the land areas close enough to a body of water to be affected by the water’s presence (e.g., areas where water-tolerant plants grow) and that affect the water itself