Western Drought:

Officials explain ‘dead pool’ and how to stop it in Lake Mead

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Southern Nevada Water Authority

Low levels at Lake Mead leave a water intake exposed. Despite the lake’s falling level, water officials say they don’t expect Lake Mead to reach dead pool levels anytime soon.

Thu, May 26, 2022 (2 a.m.)

As the water level in Lake Mead continues to drop, a scary and foreboding term is seeping up in conversations about water conservation — dead pool.

Dead pool is when the water level would get so low in a reservoir that a dam would no longer be able to produce hydropower or deliver water downstream. It’s been a subject of concern for Lake Powell and Lake Mead, which are on the Colorado River and deliver water to more than 36 million people in seven states as well as Mexico.

Lake Mead would reach dead pool if the water level dropped to 895 feet, said Patti Aaron, public affairs officer for the U.S. Bureau of Reclamation’s Lower Colorado Basin Region. As of Wednesday, the level of Lake Mead is 1,049.65 feet, she said.

“We’re not in danger of hitting dead pool,” Aaron said. “It’s not an imminent problem. It’s not something that’s going to happen tomorrow, and it’s something we don’t think is going to happen at all. We would take every action to not have that happen.”

The bureau, which manages dams, power plants and canals in the American West and is the largest wholesaler of water in the nation, is taking measures to make sure a dead pool would not occur, Aaron said. For instance, when Lake Powell was in danger of hitting a point where it wouldn’t be able to produce hydropower, the government released 500,000 acre-feet of water from Flaming Gorge Reservoir and reduced the amount of water being released from the Glen Canyon Dam on Lake Powell, Aaron said.

“Keeping these facilities working is a top priority,” Aaron said.

While the department was able to release more water further upstream from Lake Powell, in Lake Mead’s case, Lake Powell is the nearest upstream reservoir on the Colorado.

How can the bureau prevent Lake Mead from reaching a dead pool when the nearest upstream reservoir is already in trouble?

Aaron said there were two ways to help Lake Mead: One is better hydrology and more snow melt from the mountains running off into the Colorado, but that’s not in anyone’s control. The second way is through conservation by the Lower Basin states — Nevada, Arizona and California, Aaron said, “leaving water instead of taking it.”

The Bureau of Reclamation is working with its partners in funding different pilot projects and studies to conserve water, she said. Projects include lining canals so they’re not losing water due to seepage, and desalination techniques.

“There’s a finite amount of water,” Aaron said, “so we have to look at things like desalination and augmentation.”

If Lake Mead were to reach a dead pool, Las Vegas would be among the least affected areas, at least initially, as the Southern Nevada Water Authority has been investing in water infrastructure at Lake Mead for years, officials said. It recently turned on its deep-water intake No. 3 pump and the low lake level pumping station, which takes water from the bottom of the lake and carries it to the authority’s treatment facilities.

Click to enlarge photo

Southern Nevada Water Authority’s new low lake level pumping station will be able to pump water even if Lake Mead reaches dead pool. That’s because the intake feeding the station takes water from the bottom of the lake.

The older intake pump built in the 1970s has been inoperable since lake levels dropped to a point where it can no longer pump water. But with the new pump, Southern Nevada Water Authority, which provides water to more than 2.2 million residents in Southern Nevada, will be able to pump water even if Lake Mead reaches dead pool, said Bronson Mack, a SNWA spokesperson.

Southern Nevada is also upstream of Hoover Dam, and the authority’s water intake is upstream of Hoover Dam.

“We’re the only state from the Lower Basin that takes water directly from Lake Mead,” Mack said. The other Lower Basin states pull water downstream from the dam on the Colorado. From an access perspective,

Southern Nevada is in good shape, Mack said, but there is a direct connection to water conservation.

“We need to use that water supply as responsibly as possible,” Mack said. That includes minimizing outdoor water use, Mack said, since outdoor water cannot return to the lake, whereas about 99% of indoor water used in Southern Nevada is treated and released back into Lake Mead.

The other Lower basin states, however, will have it harder if a dead pool were to occur. The Bureau of Reclamation would no longer be able to deliver water to them and provide hydropower.

Taylor Hawes, the Colorado River program director for The Nature Conservancy, said the Southern Nevada Water Authority deserved credit for planning.

“They’ve been looking ahead for years,” Hawes said. “I hope the other cities in the basin will take a page from their playbook and start to implement conservation measures. We have to learn from each other right now.”

And Hawes’ hopes are coming true. Other communities are looking to Southern Nevada as a model for water conservation.

The Southern Nevada Water Authority has partnered with the Metropolitan Water District of Southern California in developing a large-scale program that will help Southern California recycle water, Mack said.

Southern California will be able to inject that reclaimed water back into the ground for recovery at a later time, Mack said.

The Southern Nevada Water Authority is providing financial assistance in the partnership, he said, and in return it is asking to get a share of California’s Colorado River water. California has the largest annual allocation of water Colorado River, whereas Nevada has the lowest.

The two parties entered into the first phase of the agreement about a year ago, Mack said, and the project is expected to take about 10 years to complete.

The project would be a big step for California; the state is trying to conserve water, but so far those attempts are falling short, according to the Los Angeles Times.

Gov. Gavin Newsom asked Californians last year to reduce their water usage by 15%, but in February the state had only conserved about 5.8%, according to a report from the Times. Water users in the northern part of California conserved the most, whereas users in the southernmost part of California — which gets its water from the Colorado River — conserved the least.

The Metropolitan Water District of Southern California declared unprecedented restrictions, including one-day-a-week watering of lawns, that are set to begin June 1.

California’s State Water Resources Control Board is also considering a ban on the irrigation of nonfunctional turf on industrial, commercial and institutional properties, a move the Nevada Legislature approved in 2021 throughout Southern Nevada. The Nevada ban takes effect in 2026, but many commercial and industrial properties already are removing turf and replacing it with xeriscaping.

Arizona, where 36% of its water supply is from the Colorado River, has also taken a lot of conservation measures. It is currently below its 1957 water usage levels, according to the Greater Phoenix Economic Council, and it has five times more water stored than it uses.

“It is unfounded to group Arizona in with other Western and Mountain West states when it comes to the shortage along the Colorado River because we’re far less reliant than competitor markets,” the economic council says on its website.

Hoover Dam also generates about 4 billion kilowatt-hours of hydroelectric power each year for Nevada, Arizona and California, according to the Bureau of Reclamation. It generates enough power to serve 1.3 million people. But due to the declining water levels, the amount of electricity produced through the dam has also decreased by 13%, Aaron said.

But hydropower is just one part of a diverse portfolio of energy sources, Aaron said. And Nevada has been pushing alternate forms of energy, like solar and wind farms. One benefit of hydropower, she added, is that it produces energy at night, unlike solar.

“It is important for people to know that we are very fortunate that Southern Nevada and our community is so close to Lake Mead,” Mack said.

Las Vegas’ proximity to Lake Mead gives it a front-row seat to what’s happening at Lake Mead, watching as the water level declines, he said. It serves as a “constant reminder that water conservation is so important,” Mack said. And with the new intake pump and low-level pumping station, we can see “Nevada’s adaptation to climate change.”

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