The city of Twin Falls' water usage has decreased in recent years, mirroring a national trend that shows water usage by cities and industries has declined in the last few decades.

Americans are using less water per person now than they have since the mid-1950s, according to a report released last week by the U.S. Geological Survey. The nation's water usage is down from a peak in 1980.

Experts said it was particularly welcome news in the burgeoning West, where cities built in dry regions are grappling with intense disputes and ecosystem collapse tied to dwindling supplies.

"Even during a time of population growth and economic growth, we are all using less water," said Susan Hutson, a USGS hydrologist in Memphis, and an author of the report. "It's exciting to see we have responded to these crises by really seeking solutions."

Twin Falls hit a peak for daily water usage in the summer of 2001, when the city used 33 million gallons in one day. Since then, usage has dropped, which city officials credit to water

efficiency efforts such as the 2004 ordinance that restricts the times and days for watering in the city.

That ordinance limits watering to three days a week before 10 a.m. and after 5 p.m., which avoids the hottest part of summer days, said Gretchen Scott, a management assistant for the city.

Additionally, the city in 1999 adopted an ordinance requiring new subdivisions to use alternative water sources for landscaping needs, such as through a canal or pond system.

"Before, all that water was potable water," said Mike Schroeder, water superintendent for Twin Falls.

Another factor is weather patterns, which also lead to a reduced demand on the city's water system, he said.

In the last several years, the closest that Twin Falls has come to the 2001 peak was 2005, when the city went through 29.9 million gallons in one day in July. This year, the city's daily peak for summer usage came on July 23, when the city used 25.4 million gallons.

Monthly totals are also down. This October, the city went through 285.5 million gallons of water. In October 2008, the city's usage was 353 million gallons.

California, in the third year of a withering drought, was the most water-hungry state in 2005, the most recent year that figures are available.

California used about 9 percent of all water extracted from lakes, rivers and underground aquifers, followed by Texas, Idaho and Illinois. Those four states combined drew more than a quarter of the country's total freshwater supplies in 2005.

Nationwide, about 80 percent of the 410 billion gallons used each day went to produce electricity at thermoelectric power plants and to irrigate farm fields.

The Associated Press contributed to this report.

Ben Botkin may be reached at bbotkin@magicvalley.com or 208-735-3238.