Every five years, the U.S. Geological Survey publishes a water usage report showing how the nation fares in water consumption. The 2010 report was published earlier this month.
In conjunction with the release of the report, media have touted that Utah is the worst in the nation for water consumption, but Molly Maupin, a hydrologist with the USGS, said it depends on the category and how the data is being compared.
She said Utah’s domestic water use is one of the highest per capita in the nation.
“In the 2005 compilation, Utah had the highest domestic per capita use,” Maupin said. “In 2010, however, Idaho just nudged you out of that prestigious location, if that is what you want to call it.”
Idaho’s per capita use is 168 gallons per day, while Utah sits at 167 gallons, according to Maupin.
Maupin said desert states’ domestic water use is typically much higher than the national average, which was around 89 gallons per person, per day in this 2010 survey.
“Arid western states have very little precipitation in the summer, and in order to keep our gardens and our grasses green, that requires a considerable amount of water,” Maupin said.
Maupin said domestic water use is not one of the major areas of water consumption, however.
The survey looks at all key categories where water is being used nationally—public supply, irrigation, industrial and, most significantly, thermo-electric water usage, in which category Utah was not a major consumer.
Maupin said the survey relies on state agencies and outside entities to provide data so they can create accurate per capita representations of water use.
The contribution of inadequate data to the survey can change the findings significantly, which can result in inaccurate comparisons of water usage improvements from state to state. Such is the case, Maupin said, when comparing Utah with its neighbor desert state Nevada, which was found to have a 25 percent decrease in domestic water use.
“Between the two compilation series, 2005 and 2010, there was a significant increase of cooperation and data exchange that was going on between USGS and the Southern Nevada Water Authority,” Maupin said. “In Las Vegas they have significant water conservation measures intact and they have a significant amount of water re-use. It’s quite likely that our 2005 data was not accurately representing that water conservation or those water savings.”
Nationally the total water use for the country declined 13 percent, with a majority of that being attributed to significant declines in the thermo-electric category.
Another unique find, according to Maupin, concerned the national public water supply.
“As the population continues to grow in the United States, the public supply total withdrawals declined. So, that was a significant new trend that we saw that we had never seen before” Maupin said.
Though there were significant national improvements over this last survey period, Maupin advises the public to be vigilant with how they use water domestically, saying there is still much room for improvement.