The U.S. Geological Survey categorizes water use for analyzing current patterns and predicting future trends.
Commercial water use includes fresh water for motels, hotels, restaurants, office buildings, other commercial facilities, and civilian and military institutions. Domestic water use is probably the most important daily use of water for most people.
Domestic use includes water that is used in the home every day, including water for normal household purposes, such as drinking, food preparation, bathing, washing clothes and dishes, flushing toilets, and watering lawns and gardens.
Industrial water use is a valuable resource to the nation's industries for such purposes as processing, cleaning, transportation, dilution, and cooling in manufacturing facilities. Major water-using industries include steel, chemical, paper, and petroleum refining. Industries often reuse the same water over and over for more than one purpose.
Irrigation water use is water artificially applied to farm, orchard, pasture, and horticultural crops, as well as water used to irrigate pastures, for frost and freeze protection, chemical application, crop cooling, harvesting, and for the leaching of salts from the crop root zone. Nonagricultural activities include self-supplied water to irrigate public and private golf courses, parks,
Livestock water use includes water for stock animals, feed lots, dairies, fish farms, and other nonfarm needs. Water is needed for the production of red meat, poultry, eggs, milk, and wool, and for horses, rabbits, and pets. Livestock water use only includes fresh water.
Mining water use includes water for the extraction of naturally occurring minerals; solids, such as coal and ores; liquids, such as crude petroleum; and gases, such as natural gas. The category includes quarrying, milling (such as crushing, screening, washing, and flotation), and other operations as part of mining activity. A significant portion of the water used for mining, about 32 percent, is saline.
Public Supply water use refers to water withdrawn by public and private water suppliers, such as county and municipal water works, and delivered to users for domestic, commercial, and industrial purposes. In 1995, the majority of the nation's population, about 225 million, or 84 percent, used water delivered from public water suppliers. About 42 million people supplied their own water, with about 99 percent of that water being groundwater, usually from a local well.
Thermoelectric Power water use is the amount of water used in the production of electric power generated with heat. The source of the heat may be from fossil fuels, nuclear fission, or geothermal. Fossil fuel power plants typically reuse water. They generate electricity by turning a turbine using steam power. After the steam is used to turn the turbines, it is condensed back to water by cooling it. The condensed water is then routed back to the boiler, where the cycle begins again.
Trends from 1950 to 1995
After continual increases in the nation's total water withdrawals (fresh water and saline water) for the years reported from 1950 to 1980, withdrawals declined from 1980 to 1985 and remained fairly constant from 1985 to 1995. The 1995 estimate of total withdrawals (402,000 MGD) is about 2 percent less than the 1990 estimate and nearly 10 percent less than the peak year of 1980. Likewise, total fresh-water withdrawals for 1995 were about 8 percent less than in 1980.
The decline in withdrawals is especially significant in light of the fact that population posted an increase of 16 percent during the same period. Clearly as a nation, the United States is using its surface water and groundwater resources more efficiently. This decline signals that water use responds to economic and regulatory factors, and that the general public has an enhanced awareness of water resources and conservation issues.
