The Colorado River Is Shrinking. See How Authorities Are Trying to Save It.
Combined storarge of the two biggest reservoirs in the Colorado River Basin
Note: Annual averages
After years of impasse between states, the federal government has stepped in to try to save the beleaguered Colorado River.
The plans include a short-term fix for an ailing reservoir and longer-term efforts to keep the river flowing. It is unclear how effective these measures will be.
The Colorado River provides water for 40 million people and more than 5 million acres of farmland. But drought and overuse have drained its reservoirs.
The Bureau of Reclamation announced in April moves to boost water levels of Lake Powell, which straddles the border of Arizona and Utah. The massive reservoir was at risk of falling below levels needed to generate hydropower. Its dam helps provide electricity for hundreds of thousands of homes across seven Western states.
Officials channeled water into Powell from an upstream reservoir and cut planned releases from the lake by 20%. So far, the efforts seem to be working. Projections now show levels staying just above “minimum power pool” through next March, when the reservoir is expected to be its lowest.
Years of drought and overuse have left Lake Powell’s water levels near historic lows.
Officials were projecting that levels would fall below those needed to produce hydropower.
After a much-needed infusion, the lake’s levels are now expected to just make it above “minimum power pool” next year.
Notes: Dead pool is the level below which water cannot flow through the dam's outlets. Current levels as of Aug. 1. Projections for March 2027. Elevations above sea level. Not to scale.
Powell’s problems have been exacerbated by exceptionally dry conditions this year. Record-low snowpack in many parts of the Rockies last winter deprived the river of needed replenishment. Runoff into Powell is now far below historic averages.
Daily inflows into Lake Powell
Note: Seven-day moving averages
The dry conditions follow a “megadrought” that has gripped the region since 2000. Reduced river flows have made it harder to meet the needs of states downstream of Powell, leading to more frequent deficits over the last 25 years.
Lake Powell’s water budget
Water released downstream
Notes: Includes losses to evaporation; does not include bank storage
To compensate for these deficits, officials have taken water from Powell. Years of drawing down the reservoir—and the larger Lake Mead—have taken a toll. Last month marked a grim milestone: the combined volume of both reservoirs hit their lowest level since 1957, when Glen Canyon Dam was still under construction.
While the recent federal actions offered a lifeline for Powell, they shifted water around rather than addressing systemwide deficits. Jack Schmidt, director of the Center for Colorado River Studies at Utah State University, likened the measures to rearranging deck chairs on a sinking ship. “The ship continues to sink,” he said.
New proposals by the Bureau of Reclamation may do more.
The bureau is weighing in now because the seven Western states that rely on the river couldn’t agree on a plan of their own. Upper basin states of Colorado, Utah, Wyoming and New Mexico have been aligned against lower basin states of Arizona, California and Nevada. As water supplies have shrunk, each side has insisted that the other cut consumption.
On average, lower basin states have consumed about twice as much as the upper basin over the last 25 years. And while they have used less in recent years, it hasn’t been enough to steady the system.
Under the new federal plan, the lower basin could have to cut consumption by up to 40% from allotted levels.
Annual consumption of Colorado River water by lower basin states
7.5/yr
Historic
allocation
4.5/yr
With max.
proposed cuts
Lower basin states have objected, including Arizona, which would be hardest hit because of its lower rights to the river. “Such reductions would devastate Arizona’s water users and its economy,” state officials warned.
The federal plan also calls for potential reductions in releases from Powell and voluntary conservation measures by upper basin states.
Agriculture accounts for more than two-thirds of Colorado River consumption and potentially offers significant savings.
Options include “more efficient irrigation, less water-intensive crops and short-term fallowing of fields,” according to Michael Cohen, a senior fellow at the Pacific Institute.
Lower basin states now await details on how much they may have to cut.
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