LAS VEGAS — A wet May across the West boosted monthly projections of water levels at Lake Mead through next year and into 2017, federal water managers said Monday, offering hope that supply cuts can be avoided in the Southwest.
A 24-month look ahead by the U.S. Bureau of Reclamation said the surface level of the largest Colorado River reservoir should remain above a benchmark level used to determine if full deliveries will be made in a seven-state region home to about 40 million residents, farms, tribes and businesses.
Last month, the bureau reported that the lake behind Hoover Dam could reach a low point in January 2017 that would force reductions for Arizona and Nevada.
“Today’s numbers say we’re projected to not be in shortage in 2016,” said Dan Bunk, bureau water operations manager in Boulder City. “There’s still a ways to go for 2017, but it’s looking better.”
The bureau is expected to make all its agreed-upon Colorado River water deliveries in Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming at least through December 2016, Bunk said.
The surface level of Lake Mead is closely watched, and closely controlled. It can fluctuate during the year, and has reached record lows several times during an ongoing drought that has lasted some 15 years.
“We’re in the 13th of 16 years where inflow will be below normal,” Bunk said.
But as long as the lake surface level is at least 1,075 feet above sea level when crucial measurements are taken in January, delivery cuts to Arizona and Nevada can be avoided.
Monday’s report projects that Lake Mead will be at 1,079 feet at the end of 2016.
The lake was 37 percent full Monday — no improvement from last month — with a surface level just 6 inches above 1,075 feet.
The big improvement came upstream, at Lake Powell. The reservoir near the Utah-Arizona line rose from 45 percent to 51 percent full, which Bunk said would allow for robust flows from Powell to Mead in weeks to come.
May became the wettest May on record for the Lower 48 states, dating to 1895.
Texas and Oklahoma were the soggiest, but six of the seven states that draw water from the Colorado River reported precipitation levels above normal. California lagged, reporting 70 percent.
Brian Fuchs, climatologist with the National Drought Mitigation Center at the University of Nebraska in Lincoln, Nebraska, said that despite regional rains, the main driver for the Colorado River Basin water outlook is snow in the Rocky Mountains.
Colorado’s mountain snowpack, despite recent snows, was 82 percent in May and just about or below normal for the year, Fuchs said.
“We are definitely continuing to see multiyear drought issues in the West,” he said.