Las Vegas turns on low-level #LakeMead pumps designed to avoid a ‘Day Zero’ — The #Nevada Independent #ColoradoRiver #COriver #aridification

To address unprecedented drought conditions and provide long-term protection of Southern Nevada’s primary water storage reservoir—Lake Mead— the Southern Nevada Water Authority constructed a third drinking water intake capable of drawing upon Colorado River water at lake elevations below 1,000 feet (above sea level). Intake No. 3 ensures Southern Nevada’s access to its primary water supply if lake levels continue to decline due to drought conditions. It also protects municipal water customers from water quality issues associated with declining lake levels. Photo credit: Southern Nevada Water Authority

Click the link to read the article on the Nevada Independent website (Daniel Rothberg). Here’s an excerpt:

The country’s largest man-made reservoir, Lake Mead, has dropped to such a historically low level that Las Vegas water officials have completed the process of turning on a pump station that will allow Southern Nevada to retrieve water, even under extreme conditions. The move — to turn on the pump station full bore — is an indication of how low Lake Mead has fallen over the past decade and serves as a bulwark against the possibility of Las Vegas losing physical access to its water as regional issues on the Colorado River become increasingly dire…

Intake #1 exposed. Photo credit: SNWA

Lake Mead is about 30 percent full, and the amount of water stored at the reservoir has ticked down over the last month. As of Tuesday, Lake Mead’s elevation sat at about 1,056 feet above sea level, roughly 163 feet below the reservoir’s maximum capacity. For the Southern Nevada Water Authority, that’s a notable number because the agency’s first pumping station — which removes water from the reservoir and siphons it off to customers in the valley — becomes inoperable when Lake Mead drops below 1,050 feet above sea level…

Las Vegas Lake Mead intake schematic, courtesy SNWA.

The water authority’s second pumping station allows for the retrieval of water up to 1,000 feet above sea level. But the third pumping station, the one fully turned on this month and known as the “low lake level pumping station,” allows Las Vegas officials to pump out water from even deeper, with the potential to access water when other Southwest cities cannot. Doa Ross, the water authority’s deputy general manager for engineering, said the pump station, which links to a third intake, or “third straw,” at the lake, will now serve as the city’s main pump…

At 895 feet above sea level, Ross said Lake Mead water can no longer pass through the Hoover Dam, a scenario that water managers refer to as “dead pool.” But because Las Vegas’s primary pump now extends to about 875 feet above sea level, the city will still be able to access water. In effect, Las Vegas watched the unfolding crisis on the river and prepared for the worst.

Pat Mulroy, a senior fellow at the University of Nevada, Las Vegas’ Boyd School of Law and the former longtime general manager of the Southern Nevada Water Authority, is an advocate for extensively rethinking how the Colorado River is managed. (Image: University of Nevada, Las Vegas’ Boyd School of Law)

“We invested $1.5 billion in the third intake and the low-level pumping station for a reason,” John Entsminger, the water authority’s general manager said in a recent interview. “We knew very well that this day could come and if lake elevations continue to decline, the people of Las Vegas can take comfort in the fact that they are the most water-secure city in the desert Southwest.”

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Brad Udall: Here’s the latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2021 of the Colorado River big reservoirs, natural flows, precipitation, and temperature. Data (PRISM) goes back or 1906 (or 1935 for reservoirs.) This updates previous work with @GreatLakesPeck.

“This isn’t a drought any more,” said Brad Udall, a senior water and climate research scientist at Colorado State University. “Let’s not fool ourselves. It’s aridification. It’s the long-term drying and warming of the American West. And it’s going to continue, and it’s going to get worse.”

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