Water use in the United States in 2010 was the lowest since 1965, according to a new report by the U.S. Geological Survey. Withdrawals nationwide averaged 355 billion gallons per day in 2010, a 13% decrease from 2005 levels and the largest decrease on record. Utah ranked second-highest in per capita domestic water use in 2010.
Released last week, Estimated Use of Water in the United States in 2010 (USGS Circular 1405) is the latest report from the USGS’s National Water Use Information Program, which compiles, analyzes, and disseminates the country’s water use data every five years. The 60-page report includes dozens of photos, tables, maps, and graphs documenting water use in eight categories. A summary fact sheet and downloadable state- and county-level data are also available.
In 2010, as in past years, Utah ranked among the top five states for highest per capita domestic water use. Idaho ranked first at 168 gallons per person per day, followed by Utah (167), Arizona (147), Wyoming (144), and Hawaii (144). The high usage in these western states is partially attributable to domestic landscape irrigation.
Utah’s per capita domestic water use decreased by 10% from 186 gallons per person per day in 2005. Nevada, which occupied the top position in 2005 with 190 gallons per person per day, fell to sixth in 2010 with 134 gallons per person per day, a 29% decrease likely due to stringent conservation.
As in 2005, four states—California, Texas, Idaho, and Florida—accounted for more than 25% of the country’s water use. California, Texas, and Idaho produce much of the country’s food despite their dry climates, while Texas and Florida require large withdrawals to generate power.
Nationwide, thermoelectric power accounted for nearly half (45%) of all water withdrawals in 2010. While only a small portion of this water was consumed, it represents a significant demand on the nation’s water supply. Irrigation accounted for 33% of withdrawals and the largest consumptive use. Irrigation withdrawals were largest in the West, while most thermoelectric power withdrawals occurred in the East.
Utah, however, has a different distribution than the country on average. Withdrawals averaged 4.5 billion gallons per day in 2010, or about 1% of the country’s total. Irrigation accounted for 72% of the state’s withdrawals, with public supply (15%) and mining (6%) following.
The 2010 U.S. estimate of 355 billion gallons per day is the lowest since 1965. Withdrawals from 1970 through 2005 hovered around 400 billion gallons per day, peaking at 430 billion gallons per day in 1980. Water use declined by 13% from 2005 to 2010, the largest decrease on record.
Withdrawals declined in six categories since 2005: public supply, self-supplied domestic, irrigation, livestock, self-supplied industrial, and thermoelectric power. Mining and aquaculture withdrawals increased but represent only a small portion of total water use.
The overall decline in water use coinciding with an increase in population suggests that the country is using water more efficiently and that conservation efforts have been effective.
The report is available at http://water.usgs.gov/watuse/.Graphics: USGS, USGS, Wasatch Water Review