National Water Use Hits 45-Year Low

Water use across the country reached its lowest recorded level in nearly 45 years. According to a new USGS report, about 355 billion gpd were withdrawn for use in the entire United States during 2010.

This represents a 13% reduction of water use from 2005 when about 410 Bgal/d were withdrawn and the lowest level since before 1970.

​California accounted for 11% of the total withdrawals for all categories and 10% of total freshwater withdrawals for all categories nationwide. Texas accounted for about 7% of total withdrawals for all categories, predominantly for thermoelectric power, irrigation and public supply.

Florida had the largest saline withdrawals, accounting for 18% of the total in the country, mostly saline surface-water withdrawals for thermoelectric power. Oklahoma and Texas accounted for about 70 percent of the total saline groundwater withdrawals in the United States, mostly for mining.

Water withdrawn for thermoelectric power was the largest use nationally, with the other leading uses being irrigation, public supply and self-supplied industrial water, respectively. Withdrawals declined in each of these categories. Collectively, all of these uses represented 94% of total withdrawals from 2005-2010.

A number of factors can be attributed to the 20 percent decline in thermoelectric-power withdrawals, including an increase in the number of power plants built or converted since the 1970’s that use more efficient cooling-system technologies, declines in withdrawals to protect aquatic habitat and environments, power plant closures and a decline in the use of coal to fuel power plants.

For the first time, withdrawals for public water supply declined between 2005 and 2010, despite a 4 percent increase in the nation’s total population. The number of people served by public-supply systems continued to increase and the public-supply per capita use declined to 89 gpd in 2010 from 100 gpd in 2005.

Declines in industrial withdrawals can be attributed to factors such as greater efficiencies in industrial processes, more emphasis on water reuse and recycling, and the 2008 U.S. recession, resulting in lower industrial production in major water-using industries.

In a separate report, USGS estimated thermoelectric-power withdrawals and consumptive use for 2010, based on linked heat- and water-budget models that integrated power plant characteristics, cooling system types and data on heat flows into and out of 1,290 power plants in the United States. These data include the first national estimates of consumptive use for thermoelectric power since 1995, and the models offer a new approach for nationally consistent estimates.

Source: U.S. Geological Survey