LAS VEGAS (KLAS) — New projections show Lake Mead dropping about 9 feet between now and October of 2024 — but keeping an extra 2.57 feet compared to forecasts from just a month ago.
The 24-month study for October 2023 from the U.S. Bureau of Reclamation is the first forecast of the 2023 water year, which runs from Oct. 1, 2023, to Sept. 30, 2024. And the “most probable” forecast is much better than last year, when Las Vegas was nervously watching the lake shrink. Lake Mead provides 90% of the valley’s drinking water.
Currently, the surface of Lake Mead is at 1,066.23 feet above sea level (as of noon Tuesday). The new forecast shows the lake dropping to 1,056.94 feet in October 2024. Just last month, that number was 1,054.37 feet.
The lake is even expected to briefly rise above 1,070 feet during January, February and March. But the federal government makes its water shortage determination in August, when the lake is expected to be down to 1,055.69 feet.
The first-ever water shortage was declared in August 2021 by the federal government. That Tier 1 shortage became a Tier 2 shortage last year during an extremely dry year. But a wet winter changed conditions this year, and operations will return to Tier 1 in 2024.
Lake Mead dropped to 1,041.71 feet on July 27, 2022 — the lowest since the reservoir was filled in the 1930s. Lake Mead is the largest reservoir in the U.S.
Conservationists and government officials agree that the wet winter didn’t solve the water shortage. During the course of the 23-year drought, climate change has reduced the amount of water in the Colorado River River Basin. There is more water guaranteed to various groups than water that actually flows down the river now.
Why did the forecast improve?
But changes have made a difference, according to the Bureau of Reclamation.
“Lake Mead’s release in 2023 is projected to be the lowest in 30 years, approximately one and half million acre-feet lower than an average normal year, reflecting extensive, ongoing conservation efforts in the Lower Basin states funded in part by President Biden’s historic Investing in America agenda, above-normal inflows in the lower basin below Hoover Dam, and conservation in Mexico,” an August statement from Reclamation said.
An acre-foot is equal to 325,851 gallons, or enough to supply two to three households for a year.
The 40 million people who rely on Colorado River water go into the new water year with Lake Mead at 34% full, Lake Powell at 38% full, and other reservoirs upstream at 69% or higher capacity: Flaming Gorge, 88% full; Navajo, 69% full; Blue Mesa, 74% full; Morrow Point, 89% full; and Fontenelle, 83% full.
And while it’s far too early to predict water supply next spring, precipitation in the Upper Colorado River Basin is off to a big start. Precipitation is at 123% of normal and snowpack is at 387% of normal. Snowpack levels won’t really matter until April 1, when officials will use measurements to estimate streamflow as the snow melts. 8 News Now will monitor those levels through the winter.
Lake Powell is an important part of the whole picture. Created by Glen Canyon Dam, which was finished in 1966, Lake Powell is the nation’s second-largest reservoir. It’s famous for houseboating and other recreation.
And just about all the water that’s in Lake Mead is there because it was released from Glen Canyon Dam. Occasional storms and floods have almost no impact on Lake Mead’s level.
Decisions on how Glen Canyon Dam is managed affect both Lake Powell and Lake Mead.
Today, Lake Powell is at 3,573 feet. The 24-month study shows that level climbing to 3,588.46 feet in October 2024. That’s a big change from last month’s forecast, which expected Lake Powell to be at 3,595.28. That’s a difference of almost 7 feet.