A megadrought and warmer climate have brought Lakes Mead and Powell to their lowest levels in decades, leading the federal government to implement its first-ever cutbacks for water delivery.
The Bureau of Reclamation (BOR) recently released the Colorado River Basin 24-Month Study for August to set annual operations for Lake Powell and Lake Mead in 2022 based on anticipated reservoir water levels.
“Given the ongoing historic drought and low runoff conditions in the Colorado River Basin, downstream releases from Glen Canyon Dam and Hoover Dam will be reduced in 2022 due to declining reservoir levels,” BOR said in a statement. “In the Lower Basin, the reductions represent the first ‘shortage’ declaration—demonstrating the severity of the drought and low reservoir conditions.”
According to the BOR, an exceptionally dry spring in 2021 in the Upper Basin of the Colorado River has led to Lake Powell receiving just 26 percent of normal April to July runoff despite near-average snowfall last winter.
As of August, total Colorado River system storage is 40 percent of capacity, down from 49 percent at this time last year. As a result of the lack of runoff, the BOR will operate Lake Powell in the Mid-Elevation Release Tier in the water year 2022 (Oct. 1, 2021 through Sept. 30, 2022), and Lake Mead will operate in its first-ever Level 1 Shortage Condition in the 2022 calendar year.
“The announcement today is a recognition that the hydrology that was planned for years ago, that we hoped we would never see, is here today,” Camille Touton, BOR deputy commissioner, said at a news conference that brought together officials from all the states impacted.
Lake Powell
Under the Mid-Elevation Release Tier, Lake Powell will release 7.48 million acre-feet in the 2022 water year without the potential for a mid-year adjustment in April 2022. An acre-foot is 325,851 gallons, or the amount of water needed to cover one acre of land to a depth of one foot.
The study projects Lake Powell’s Jan. 1, 2022, elevation to be 3,535.40 feet—about 165 feet below full levels.
As part of the 2019 Colorado River Drought Contingency Plan and the Colorado River Compact, upper river states and BOR released more water from upstream reservoirs to keep Lake Powell from dropping below 3,525 feet. On July 23, Lake Powell’s level fell to 3,555.09 feet. The previous record low was set in April 2005.
Under the Colorado River Compact, upper river states—Colorado, New Mexico, Utah and Wyoming—meet their downstream water delivery obligations to the Lower Basin states of Arizona, California, Nevada and Mexico through water deliveries from Lake Powell to Lake Mead.
To satisfy arrangements made with the states, the BOR announced it would increase the average daily releases from the Blue Mesa Reservoir in Gunnison County, CO; Flaming Gorge Dam in Wyoming; and the Navajo Reservoir, which straddles the Colorado/New Mexico border, for a total of 181,000 acre-feet between the three reservoirs.
Shortly after the BOR announcement on the water releases, the agency was asked about the potential of future drought years.
“We are preparing for that now, by modeling,” Christopher Cutler, a manager in the water and power services for BOR, told the Colorado Sun. “So we’re modeling not only normal hydrology next year, but dry and extremely dry.”
While Upper Basin states do not use their water allocation, they take on the burden of dealing with declining flows of the Colorado River. Lower Basin states have consistently used more than 7.5 million acre-feet annually, whereas Upper Basin states have consistently used about 4 million acre-feet since 1990.
“That means the Upper Basin has to be sure it has the tools in place to make sure it can continue to meet its compact obligations, to send water out of Lake Powell,” John Fleck, director of water resources at New Mexico State University, told Water Education Colorado.
Lake Mead
Based on projections in the 24-Month Study, Lake Mead levels will be at 1,065.85 feet—about 9 feet below the Lower Basin shortage determination trigger of 1,075 feet, and about 24 feet below the drought contingency plan trigger of 1,090 feet.
As a result of the lower lake levels, BOR has triggered a Level 1 Shortage Condition for the first time ever. Level 1 restrictions will affect mostly Arizona with reductions of 512,000 acre-feet, approximately 18 percent of the state’s annual apportionment, starting next year. Arizona gets 36 percent of its water from the Colorado River.
The Drought Contingency Plan stipulates that farmers and ranchers in the state will bear the brunt of the cutbacks, sparing most cities. According to AZ Central, producers in Pinal County—which ranks first in the state for cotton, barley and livestock production, and second in the state for durum wheat and alfalfa hay production—expect water deliveries to drop by half next year and disappear altogether in 2023. Despite securing $45 million from state and federal agencies to drill more wells and other infrastructure to offset the losses, farmers stated they expect to leave a third of their acreage fallow.
The Arizona Farm Bureau stated the cutbacks will have a “devastating impact” on producers and the surrounding communities. The bureau stated, despite farmers spending decades of money to manage water wisely, “You are the first to lose access to this most precious resource.”
Arizona Farm Bureau President Stefanie Smallhouse said, “To ensure that food can continue to be safely and affordably produced in the West, significant investments in water infrastructure are needed. The Arizona agriculture industry annually contributes $23 billion to the economy.
“Supporting an effort to improve existing water infrastructure and fund new technologies will benefit our current economy and allow more flexibility to conserve this precious resource, all while continuing to provide food security here at home.”
Agriculture is not the only industry that will be affected. Lower levels in the Colorado River will diminish hydroelectricity production from Lake Mead and Lake Powell. According to Patti Aaron, BOR public affairs officer, every foot of water lost equates to about six megawatts less power generated. Six megawatts roughly translates to the power consumed by 800 homes. At Lake Mead’s highest level in 2000, the Hoover Dam powered roughly 450,000 homes. At its current level, it powers 350,000 homes and provides electricity for Nevada, Arizona and Southern California.
Nevada will also experience cutbacks of 7 percent or 21,000 acre-feet. Mexico, which also has junior water rights in the agreement, will have cutbacks of 80,000 acre-feet, or approximately 5 percent of the country’s annual allotment.
“While these agreements and actions have reduced the risk, we have not eliminated the potential for continued decline of these critically important reservoirs,” Touton said in a statement. “Reclamation is committed to working with all of our partners in the basin and with Mexico in continuing to implement these agreements and the ongoing work ahead.” — Charles Wallace, WLJ editor
