US Water demand

From Water Wiki

Estimates of water use from the United States Geological Survey of the United States "indicate that about 408 billion gallons per day (one thousand million gallons per day, abbreviated Bgal/d) were withdrawn for all uses during 2000. This total has varied less than 3 percent since 1985 as withdrawals have stabilized for the two largest uses—thermoelectric power and irrigation."

"Irrigation remained the largest use of freshwater in the United States and totaled 137 Bgal/d for 2000." However, thermoelectric usage is the largest overall water (including freshwater and saline) user in the US.

graphic from the USGS survey

Methodology - States submit estimates for each water user that is developed from site-specific inventory or representative surveys or some combination of both. The report states, "Compilation of accurate data for the largest public suppliers, industries, agricultural regions, and powerplants produces State totals that are fairly reliable." Methodology for collecting the 2000 data is described on the USGS website. Methodology for the upcoming 2005 water usage survey is also available.