Lake Mead Water Supply Given Hope From Rockies Snowpack

The first major snowstorm of the season in the Rocky Mountains has brought welcome news to regions relying on the Colorado River, including Lake Mead and Lake Powell.
As the early winter storm blanketed the Denver metro area with nearly 20 inches of snow—almost triple the month’s average—snowpack in the nearby Rocky Mountains surged to promising levels, creating optimism for drought-stricken areas downstream.
The snowpack in the Upper Colorado River Basin, where the river’s headwaters are located, is currently at 137 percent of normal, a hopeful start to the season as winter approaches.
Some of the greatest accumulations were recorded in regions such as Colorado’s Gunnison Basin at 176 percent normal and Dolores Basin at an impressive 234 percent, according to U.S. Bureau of Reclamation (USBR) data.
The Lower San Juan region, straddling Colorado and Utah, tops the charts at a whopping 1,850 percent of normal snow accumulation.
The figures are given as the median snow water equivalent (SWE)—a measure of the water contained in the snow—compared to a 30-year average for the time of year—a crucial metric in determining how much water ends up downstream.
The Colorado River acts as the primary source of water for millions in the Southwest, including users in Arizona, Nevada, and California.
The current high SWE readings are promising, especially in the Colorado Headwaters region—an important feeder for the river—at 129 percent of average, and offer hope for Lake Mead’s ongoing recovery.
The Colorado River Basin has endured over two decades of drought, significantly impacting Lake Mead, which is currently around 1,061 feet above sea level, according to Lakes Online.
Though recent wet winters have offered some relief, the reservoir remains more than 160 feet below the full pool.
A historically low level of 1,041.7 feet in July 2022 underscored the severity of the drought. Since then, consecutive years of above-average snowfall and moisture-fed storms in 2023 have brought a partial recovery.
Lake Powell, which is upstream of Lake Mead, is currently at 3,576 feet above sea level, about 5 feet higher than this time last year.
Meanwhile, as of November 12, Lake Mead’s levels remain approximately four feet lower than the same period last year.
Despite this early snowfall, climate patterns suggest a mixed outlook for the winter. The National Oceanic and Atmospheric Administration (NOAA) recently forecasted a developing La Niña, which historically brings drier conditions to the Southwest.
If La Niña strengthens, it could challenge snow accumulation and limit the volume of runoff feeding into the Colorado River come spring.
Also, early-season snowpack statistics like this week’s 137 percent measurement are no guarantee of conditions in April, the season’s critical endpoint. Historically, SWE averages stabilize closer to April, with last year reaching 111 percent of normal, thanks in part to January snow preserved by unusually cold temperatures.
“It really isn’t until early January that we have a sense of where snowpack is going and even then it things can change,” Eric Balken, executive director of The Glen Canyon Institute, told Newsweek.
Balken also said that in recent years, the correlation between snowpack and runoff to the river has weakened as warmer air and drier soils have sucked up more moisture.
“You don’t fully know what’s gonna happen with runoff or reservoirs until March. It’s kind of like trying to predict the stock market. You know, there’s there’s all sorts of data out there that you can look at and maybe you’ll be right, but you probably won’t be.”
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