New research indicates there is little correlation between drought or dry conditions in a locality and the amount of water its citizens use. For instance, a family in Phoenix, Ariz., which is one of the driest and most drought-plagued U.S. cities, uses the most water in the country — 131,400 gallons per year.
On the other hand, citizens of Seattle, Wash. use about 47,000 gallons of water per year.  Seattle tends to receive ample rainfall each year.
"We must also remember that water costs considerably more in Seattle than in Phoenix," says Klaus Reichardt, CEO and founder of Waterless Co. Inc. "When costs go up, households and facilities tend to use water more efficiently."
After Phoenix, the researchers found the following to be the most water consuming cities in the country:
1.   Los Angeles
2.   Dallas, TX
3.   El Paso, TX
4.   Denver, CO
5.   San Antonio, TX
6.   Chicago
7.   Miami, FL
8.   New York City
9.   Houston, TX

"It is interesting to note that four of the top water consuming cities in the country are in Texas," adds Reichardt. "A factor that may play a role here is that water rates in Texas have been kept artificially low for years…a situation that is changing rapidly."
Source: American Water Intelligence.  Figures reflect typical monthly bill for single-family home using 7,500 gallons of water.