Is the Colorado River Drying Up?
The start of 2023 has brought severe storms to much of the southwestern United States. But despite the rain and snow, water levels in the nation's two largest reservoirs are still well below average.
Lake Mead and Lake Powell are the largest and second-largest water reservoirs in the U.S., respectively. Both reservoirs are fed by the Colorado River, a 1,450-mile-long waterway that stretches from the Rocky Mountains to northern Mexico.
The river supplies water to millions of people across the southwest, but over the last century, the U.S. Geological Survey estimates that the river's flow has dropped by 20 percent.
"The Colorado River has experienced an extended drought for the past 23 years, exacerbated by climate change," Jennifer Pitt, Colorado River program director for the non-profit environmental organization, the National Audubon Society, previously told Newsweek. "Rising temperatures are drying out the region, resulting in less flow in the river."
At the start of January, the city of Scottsdale in Arizona was forced to cut off its water supply to the Rio Verde Foothills after concerns that its allocated supplies from the Colorado River would not be enough to serve its own residents.
Luckily, the rain and snow in recent weeks has gone some way to improve the state of the drought-stricken Colorado River, Haley Paul, Arizona policy director for the National Audubon Society, previously told Newsweek. "These storms have delivered above average snowpack for this time of year, as well as above normal river flows."
But how has this affected the river's most-important reservoirs?
Lake Powell Water Levels
Since the summer of 2022, water levels in Lake Powell have been steadily declining. Water levels are now at 3,524 feet above sea level, just 24 percent of its full storage capacity.
The reservoir reached record low levels in April 2022, dropping to 3,519 feet above sea level.
Lake Powell, which sits at the border between Arizona and Utah, is fed mainly by runoff from snowpack in Colorado, Utah and Wyoming.
"About 75 to 80 percent of inflow into Lake Powell comes from runoff of melting snowpacks that accumulate over the winter period," Amee Andreason, a spokesperson for the Bureau of Reclamation, told Newsweek. "The remainder comes from rain in the non-winter months. Only water that falls within the Upper Colorado River Basin flows into Lake Powell."
Snowpack across Colorado is at 130 percent of what it usually is at this time of year, which is good news for the Colorado River and its reservoirs. However, Andreason said that "it will take several really wet years to result in enough inflow to Lake Powell to recover its water storage to pre-drought conditions."
Lake Mead Water Levels
In July 2022, Lake Mead's water levels reached an all-time low of 1,040 feet. Over the last few weeks, water levels have risen very slightly, from 1,045 feet at the beginning of January to 1,046 feet today. The increase is likely because of the heavy rain that has swept through California and Nevada over this period.
However, this is still only 29 percent of the lake's full storage capacity. What is more, a study, published by the Bureau of Reclamation last week, suggests that the reservoir could reach a new all-time low in 2023.
The recent rain and snow gave a hopeful sign for the year to come, but more than a few weeks of wet weather is needed to relieve the decades-long megadrought that has gripped the U.S. southwest.
"The water-supply forecasts look to be above average," Paul said. "But, remember, because our reservoirs—particularly Powell and Mead—are so low from 23-plus years of drought, it would take many years of above-average snow and runoff to refill the reservoirs.
"We cannot take our eye off the ball in terms of figuring out how to use less water from the Colorado River to prevent the reservoirs from falling to catastrophically low levels."
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