USGS Kansans Are Using Less Water By Brian Grimmett • Jul 3, 2018 U.S. Geological Survey Kansas water use is declining, according to a new report from the U.S. Geological survey. In 2015, Kansas used on average more than 4 billion gallons of water each day. That’s down nearly 25 percent from 1990. Of that, 2.6 billion gallons per day are used for irrigation — a decrease of 36 percent from 1990. “What we’re doing is great, it’s just not enough of it,” said Kansas Water Office Director Tracy Streeter.