Lake Mead’s decline may lead to drastic water cutbacks, feds say

The top of water intake valve No. 1 became visible in late April in Lake Mead. A third straw an ...

A megadrought is draining Lake Mead faster than anticipated. Don’t expect things to improve anytime soon.

Without wholesale water use reductions in the near future, the situation is dire enough that Lake Mead could drop to a level that it would not be able to provide drinking water, irrigation and power to millions of people by fall 2023, a top federal water official says.

Water shortages and demand on the Colorado River Basin will require reductions in water use of 2 million to 4 million acre-feet by fall 2023 to keep Lake Mead functioning, Bureau of Reclamation Commissioner Camille Calimlim Touton told the Senate Committee on Energy and Natural Resources Committee in testimony Tuesday.

If entities that use the water could not reach agreement within 60 days on a plan to reduce consumption, the Interior Department could mandate cutbacks and would do so, Touton indicated.

The bureau’s latest 24-month outlook released last week said it is forecasting the “most probable” lake level will be 1,014.86 feet by September 2023, about 9 feet lower than projections made just a month ago.

Lake Mead has dropped to an all-time low of 28 percent of capacity. The water level was 1,044.88 feet as of 6 p.m. Thursday, a decline of nearly 6 feet in the past month. A year ago the lake was 1,070.5 feet (above sea level).

The lake is the largest man-made reservoir in the country, and in the early 1980s held an estimated 28 million acre feet of water. Water came over the top of Hoover Dam in spring 1983. Over the past two decades, the lake has fallen steadily as sustained drought, increased water demand and over-allocation of water have led to an endangered future.

“There is so much to this that is unprecedented,” Touton, a Nevada native, told lawmakers. “But unprecedented is now the reality and the normal in which Reclamation must manage our system, for warmer, drier weather is what we are facing.”

Nearly 25 million residents and farmers, including those in major cities such as Las Vegas, Los Angeles, San Diego, Phoenix and others rely on the lower Colorado River system.

Touton said climate change — including hotter temperatures leading to less snowfall, drier soil and other conditions — have created declines in water systems never seen before. She said the new reality applies to every river basin the agency manages, but the Colorado River is the largest and most urgent focus.

Last August, the federal government declared a shortage on the Colorado River for the first time, triggering substantial cutbacks in water deliveries to Arizona, Nevada and Mexico. Some Arizona farmers have left some fields dry and unplanted, and have turned to more groundwater pumping.

Southern California has not yet faced reductions, but it’s likely that will change as reservoirs keep dropping.

Continued decline of the lake will lead to a second round and more drastic reductions in coming months unless states and Indian tribes reach an agreement on reductions by mid-August.

The Bureau of Reclamation normally sends nearly 7.48 million acre-feet of water from Lake Powell into Lake Mead in the early summer, but opted to reduce that to 7 million-acre feet this year because Lake Powell power generation is endangered by never-before-seen low water levels. The sending of less water downstream has been a factor in Lake Mead’s speedier decline.

In late April and after years of construction, the Southern Nevada Water Authority turned on pumps for a $1.3 billion “third straw” and pumping station to ensure Southern Nevada could draw its share of water from the lake. If the lake were to drop to 895 feet, the pumping station would not be able to draw water, according to SNWA officials. Southern Nevada depends on Lake Mead for 90 percent of its water.

“We are 150 feet from 25 million Americans losing access to the Colorado River, and the rate of decline is accelerating,” Entsminger told senators, according to the Los Angeles Times.

Under the 1922 Colorado River Compact by which the water is divided, California gets 4.4 million acre-feet of water per year. Arizona’s allotment is 2.8 million acre-feet. The Las Vegas Valley consumed roughly 242,000 acre-feet of water last year, according to the SNWA. That’s more than 90,000 acre-feet, or about 26 billion gallons, less than the valley consumed in 2002 when it had about 1 million residents, less than half of what it has today.

Contact Marvin Clemons at Follow @Marv_in_Vegas on Twitter.