Glossary of Water Use Terms
acre-foot (acre-ft)
the volume of water required to cover 1 acre of land (43,560 square feet) to a depth of 1 foot.
aquifer
a geologic formation, group of formations, or part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to wells and springs.
commercial water use
water for motels, hotels, restaurants, office buildings, other commercial facilities, and institutions. The water may be obtained from a public supply or may be self-supplied.
consumptive use
that part of water withdrawn that is evaporated, transpired, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. Also referred to as water consumed.
conveyance loss
water that is lost in transit from a pipe, canal, conduit, or ditch by leakage or evaporation. Generally, the water is not available for further use; however, leakage from an irrigation ditch, for example, may percolate to a ground-water source and be available for further use.
cooling water
water used for cooling purposes, such as of condensers and nuclear reactors.
delivery/release
the amount of water delivered to the point of use and the amount released after use; the difference between these amounts is usually the same as the consumptive use.
domestic water use
water for household purposes, such as drinking, food preparation, bathing, washing clothes and dishes, flushing toilets, and watering lawns and gardens. Also called residential water use. The water may be obtained from a public supply or may be self supplied.
evaporation
process by which water is changed from a liquid into a vapor.
evapotranspiration
a collective term that includes water discharged to the atmosphere as a result of evaporation from the soil and surface-water bodies and as a result of plant transpiration.
freshwater
water that contains less than 1,000 milligrams per liter (mg/L) of dissolved solids; generally, more than 500 mg/L of dissolved solids is undesirable for drinking and many industrial uses.
ground water
generally all subsurface water as distinct from surface water; specifically, that part of the subsurface water in the saturated zone (a zone in which all voids are filled with water) where the water is under pressure greater than atmospheric.
hydroelectric power water use
the use of water in the generation of electricity at plants where the turbine generators are driven by falling water.
industrial water use
water used for industrial purposes such as fabrication, processing, washing, and cooling, and includes such industries as steel, chemical and allied products, paper and allied products, mining, and petroleum refining. The water may be obtained from a public supply or may be self supplied.
instream use
water that is used, but not withdrawn, from a ground- or surface-water source for such purposes as hydroelectric power generation, navigation, water-quality improvement, fish propagation, and recreation. Sometimes called nonwithdrawal use or in-channel use.
irrigation district
a cooperative, self-governing public corporation set up as a subdivision of the state government, with definite geographic boundaries, organized and having taxing power to obtain and distribute water for irrigation of lands within the district; created under the authority of a state legislature with the consent of a designated fraction of the landowners or citizens.
irrigation water use
artificial application of water on lands to assist in the growing of crops and pastures or to maintain vegetative growth in recreational lands such as parks and golf courses.
livestock water use
water for livestock watering, feed lots, dairy operations, fish farming, and other on-farm needs. Livestock as used here includes cattle, sheep, goats, hogs, and poultry. Also included are animal specialties.
million gallons per day (Mgal/d)
a rate of flow of water.
mining water use
water use for the extraction of minerals occurring naturally including solids, such as coal and ores; liquids, such as crude petroleum; and gases, such as natural gas. Also includes uses associated with quarrying, well operations (dewatering), milling (crushing, screening, washing, floatation, and so forth), and other preparations customarily done at the mine site or as part of a mining activity. Does not include water used in processing, such as smelting, refining petroleum, or slurry pipeline operations. These uses are included in industrial water use.
offstream use
water withdrawn or diverted from a ground- or surface-water source for public-water supply, industry, irrigation, livestock, thermoelectric power generation, and other uses. Sometimes called off-channel use or withdrawal.
per capita use
the average amount of water used per person during a standard time period, generally per day.
public supply
water withdrawn by public and private water suppliers and delivered to users. Public suppliers provide water for a variety of uses, such as domestic, commercial, thermoelectric power, industrial, and public water use.
public-supply deliveries
water provided to users through a public-supply distribution system.
public water use
water supplied from a public-water supply and used for such purposes as firefighting, street washing, and municipal parks and swimming pool.
reclaimed wastewater
wastewater treatment plant effluent that has been diverted for beneficial use before it reaches a natural waterway or aquifer.
recycled water
water that is used more than one time before it passes back into the natural hydrologic system.
return flow
the water that reaches a ground- or surface-water source after release from the point of use and thus becomes available for further use.
reuse
see recycled water.
saline water
water that contains more than 1,000 milligrams per liter of dissolved solids.
self-supplied water
water withdrawn from a surface- or ground-water source by a user rather than being obtained from a public supply.
surface water
an open body of water, such as a stream or a lake.
thermoelectric power water use
water used in the process of the generation of thermoelectric power. The water may be obtained from a public supply or may be self-supplied.
transpiration
process by which water that is absorbed by plants, usually through the roots, is evaporated into the atmosphere from the plant surface.
wastewater
water that carries wastes from homes, businesses, and industries.
wastewater treatment
the processing of wastewater for the removal or reduction of contained solids or other undesirable constituents.
wastewater-treatment return flow
water returned to the hydrologic system by wastewater-treatment facilities.
water transfer
artificial conveyance of water from one area to another.
water use
- In a restrictive sense, the term refers to water that is actually used for a specific purpose, such as for domestic use, irrigation, or industrial processing.
- More broadly, water use pertains to humans’ interaction with and influence on the hydrologic cycle, and includes elements such as water withdrawal, delivery, consumptive use, wastewater release, reclaimed wastewater, return flow, and instream use.
withdrawal
water removed from the ground or diverted from a surface-water source for use.