National Water Census

Total withdrawals for all categories of use in 2015 were estimated to be 322 billion gallons per day (Bgal/d), a level of withdrawal not reported since before 1970. Total withdrawals in 2015 were 9 percent less than in 2010, continuing a sharp but steady downward trend since 2005. Freshwater withdrawals were also 9 percent less than in 2015.

Surface-water sources include streams and rivers, lakes and reservoirs, and oceans. For the purposes of the USGS water-use reports, surface water with less than 1,000 milligrams per liter (mg/L) of dissolved solids is considered freshwater, and the remainder is considered saline. Surface-water resources are often evaluated by watershed. The most recent USGS water-use estimates by watershed are in...

Groundwater refers to all subsurface water, specifically that part of groundwater which is in the saturated zone. Groundwater sources are called aquifers: geologic formations that contain sufficient saturated permeable material to yield significant quantities of water to wells and springs. For the purposes of the USGS water-use reports, groundwater with less than 1,000 milligrams per liter (mg/L)...

Focus Area Studies were stakeholder-driven assessments of water availability in river basins with known or potential conflict. They contributed toward ongoing assessments of water availability in large watersheds, provided opportunities to test and improve approaches to water availability assessment, and informed the National Water Census with local information. These studies focused on key water...

Public supply refers to water withdrawn by public and private water suppliers that provide water to at least 25 people or have a minimum of 15 connections. Public-supply water is delivered to users for domestic, commercial, and industrial purposes. Part of the total is used for public services, such as public pools, parks, firefighting, water and wastewater treatment, and municipal buildings, and...

Domestic water use includes indoor and outdoor uses at residences, and includes uses such as drinking, food preparation, bathing, washing clothes and dishes, flushing toilets, watering lawns and gardens, and maintaining pools. Domestic water use includes potable and non-potable water provided to households by a public water supplier (domestic deliveries) and self-supplied water use. Self-supplied...

Irrigation water use includes water that is applied by an irrigation system to sustain plant growth in agricultural and horticultural practices. Irrigation also includes water that is used for pre-irrigation, frost protection, chemical application, weed control, field preparation, crop cooling, harvesting, dust suppression, and leaching salts from the root zone. Estimates of irrigation withdrawals...

Water for thermoelectric power is used in the process of generating electricity with steam-driven turbine generators. Since 2000, thermoelectric-power withdrawals have been compiled by cooling-system type. Once-through cooling refers to cooling systems in which water is circulated through heat exchangers, and then returned to the source. Recirculating cooling refers to cooling systems in which...

Industrial withdrawals provide water for such purposes as fabricating, processing, washing, diluting, cooling, or transporting a product; incorporating water into a product; or for sanitation needs within the manufacturing facility. Some industries that use large amounts of water produce such commodities as food, paper, chemicals, refined petroleum, or primary metals. Water for industrial use may...

Mining water use is water used for the extraction of minerals that may be in the form of solids, such as coal, iron, sand, and gravel; liquids, such as crude petroleum; and gases, such as natural gas. The category includes quarrying, milling of mined materials, injection of water for secondary oil recovery or for unconventional oil and gas recovery (such as hydraulic fracturing), and other...

Livestock water use is water associated with livestock watering, feedlots, dairy operations, and other on-farm needs. Livestock includes dairy cows and heifers, beef cattle and calves, sheep and lambs, goats, hogs and pigs, horses, and poultry. Other livestock water uses include cooling of facilities for the animals and products, dairy sanitation and wash down of facilities, animal waste-disposal...

Aquaculture water use is water associated with raising organisms that live in water—such as finfish and shellfish—for food, restoration, conservation, or sport. Aquaculture production occurs under controlled feeding, sanitation, and harvesting procedures primarily in ponds, flowthrough raceways, and, to a lesser extent, cages, net pens, and closed-recirculation tanks.