Western reservoirs could run dry in 3 years, top official warns

Source: By Jennifer Yachnin, E&E News • Posted: Tuesday, September 20, 2022

LAKE MEAD NATIONAL RECREATION AREA, ARIZONA - AUGUST 19: A bleached 'bathtub ring' is visible on the banks of Lake Mead near the Hoover Dam on August 19, 2022 in Lake Mead National Recreation Area, Arizona. The federal government announced plans to cut water allocations from the Colorado River Basin to Arizona and Nevada for the second year in a row and is asking residents to cut water consumption as the drought worsens. Water levels at Lake Mead stand at 27 percent of capacity, its lowest level since being filled in the 1930s following the construction of the Hoover Dam. The lake's water levels have fallen an estimated 175 feet since 2000. (Photo by Justin Sullivan/Getty Images)

A bleached “bathtub ring” is visible on the banks of Lake Mead on the Colorado River near the Hoover Dam on Aug. 19 in Arizona’s Lake Mead National Recreation Area. Justin Sullivan/Getty Images

A top Centennial State official warned Colorado River Basin states that the system’s federal reservoirs could effectively empty in a few short years barring aggressive reductions to water demands.

Colorado River Water Conservation District General Manager Andy Mueller painted a bleak future for the basin’s seven states — Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming — on Friday, during his organization’s annual conference in Grand Junction, Colo., on the river’s future.

“If we continue in the way we’re operating now, if we don’t reduce our demands, we’re going to really see those reservoirs really hit a crisis,” Mueller said. “I’m not talking about in 20 years, I’m talking about in the next three or four years. We have a period of time here to change our use.”

More than two decades of drought have significantly diminished the Colorado River, which spans 1,450 miles and supplies water to some 40 million individuals.

Although Bureau of Reclamation Commissioner Camille Touton instructed those seven states to find up to 4 million acre-feet in reductions, no agreements had been reached as of a mid-August deadline (E&E News PM, Aug. 16).

One acre-foot of water is equal to about 326,000 gallons, or enough water to cover a football field to a depth of 1 foot.

Under the terms of the 1922 Colorado River Compact, the seven states share 16 million acre-feet of water annually divided equally between the Upper Basin states — Colorado, New Mexico, Utah and Wyoming — and the Lower Basin states — Arizona, California and Nevada.

Mueller noted that the drought has sharply reduced that flow to 12 million acre-feet, but is likely to drop even lower under continued drought conditions.

“When we listen to the scientists today, they say plan for a 9 million acre-foot river,” Mueller said. “That’s incredibly scary because … that’s a huge economic disruption, that’s communities suffering in all the basins.”

But those lower flows have already sharply impacted federal reservoirs in the Upper Colorado basin, Mueller noted.

Under a drought operations agreement, federal officials tapped both the Blue Mesa Reservoir in Colorado and the Flaming Gorge Reservoir in Wyoming in recent years to keep water levels in the Lake Powell reservoirs high enough to maintain hydropower operations (Greenwire, May 3).

Although Reclamation officials indicated that drought response efforts could continue to rely on those upstream reservoirs, Mueller dismissed those plans as unfeasible.

“We’ve now drained Blue Mesa, we’re draining Flaming Gorge as we speak, and we have no plans for how we’re going to handle this when those reservoirs are dropped. We can’t keep doing this,” he said.

Among Mueller’s recommendations, he called for the federal government to demand the Lower Basin states to account for evaporation and transit losses in their annual water use.

Currently, when water is sent downstream, he explained that the Upper Basin states must cover those losses. For example, if California demands 100,000 acre-feet of water, the Upper Basin states must send 120,000 acre-feet to account for evaporative losses.

“There very well may be litigation if they don’t fix this problem,” Mueller warned. “Because if their threat is to come after our federal projects in the Upper Basin, we will defend those projects.”