U.S. Water Use

from USGS

According to the U.S. Geological Survey (USGS) report “Estimated Use of Water in the United States in 2010,” which is the latest data available from the USGS, The United States uses 355 billion gallons of water a day. This was a 13% reduction from 2005, the last time the data was collected by the USGS though the population of the United States increased by 4% to 313.0 million people in 2010. Part of this reduction might have been due to lingering effects from the recession, but overall water use peaked in 1980. 

The 2010 total water withdrawals were at the lowest level since before 1970. Freshwater use was 306 billion gallons/day, or 86 % of the total water use- salt water used was 48.3 billion gallons/day, or 14 % of total water use. Most of the salt water used is for cooling in power generation and 38% of freshwater used is also for power generation and is non consumptive. The water is returned to the source. Total fresh water used (including the water for power generation) was 306 billion gallons/day. Thermoelectric-power water use accounted for 45% of total water withdrawals for all uses, and freshwater withdrawals for thermoelectric power accounted for 38% of the total freshwater withdrawals for all uses. Fresh surface-water use was (230 billion gallons/day) were almost 15 % less than in 2005, and fresh groundwater use (76.0 billion gallons/day) were about 4 % less than in 2005.

Irrigation water use was 115 billion gallons/day in 2010 the lowest level since before 1965. Irrigation use accounted for 38% of total freshwater for all uses, or 61% of total freshwater withdrawals for all uses except thermoelectric power. Surface-water supplied 57% of the total irrigation withdrawals, 65.9 billion gallons/day or about 12% less than in 2005. Groundwater supplied 49.5 billion gallons/day for irrigation in 2010, about 6 % less than in 2005. While water used for irrigation decreased the USGS reports that 62,400 thousand acres were irrigated in 2010, an increase of 1.5% (950 thousand acres) from 2005. We became more efficient in water used for agriculture by increasing the use sprinkler and microirrigation systems. These types of systems are now used in 58% of irrigated lands in 2010.

Domestic water use includes indoor and outdoor uses at residences. Common indoor water uses are drinking, food preparation, washing clothes and dishes, bathing , and flushing toilets. Common outdoor uses are watering lawns and gardens or maintaining pools, ponds, or other landscape features in a domestic environment. Domestic water is either self-supplied or provided by public suppliers. Self-supplied domestic water use is typically withdrawn from a well, or captured as rainwater in a cistern. Domestic deliveries are provided to homes by public suppliers through community water systems. Public-supply water use in 2010 were 42.0 billion gallons/day, 5% less than in 2005. This was the first decline in public-supply water use since the USGS began estimating national water use in 1950.

An estimated 44.5 million people in the United States, or 14 % of the population, provided their own water for domestic use in 2010 in Virginia this is higher estimated by Virginia Tech at 21% though representing only 16% of domestic water used. (People with wells use less water for outdoor uses.) These self-supplied withdrawals were estimated at 3,600 million gallons/ day, in Virginia with a population of 8 million private wells supplied 124 million gallons/day in 2010. Nearly all (98 %) of these self-supplied water were from fresh groundwater sources. Self-supplied domestic water withdrawals are rarely metered or reported; typically this use is calculated by multiplying an estimate of the population not served by public supply by a coefficient for daily per capita private well use.

from USGS

In 2010, more than 50% of the total water use in the United States was accounted for by 12 States. The largest users of water were California and Texas which are the two largest states in the nation. California accounted for about 11% of the total water use and 10% of freshwater use in the United States. California predominantly uses water for irrigation. Texas accounted for about 7% of total water use, predominantly for thermoelectric power generation (a significant portion that is exported to California a state that imports 33% of its electric supply), irrigation, and public supply.