As Lake Mead sinks, states agree to more drastic water cuts

California, Arizona and Nevada are back in negotiations about the dwindling Colorado River water supply.

 

Three years ago, state hydrologists in the Colorado River Basin began to do some modeling to see what the future of Lake Mead — the West’s largest reservoir — might look like. If the dry conditions continued, elevations in Lake Mead, which is fed by the Colorado River, could drop much faster than previous models predicted.

For decades, the West’s big reservoirs were like a security blanket, says Anne Castle, the former assistant secretary for water and science at the Interior Department. But the blanket is wearing thin. Under normal conditions, Lake Mead loses 1.2 million acre-feet of water every year to evaporation and deliveries to the Lower Basin states plus Mexico, which amounts to a 12-foot drop. Previously, extra deliveries of water from Lake Powell offset that deficit, but after 16 years of drought and increased water use in the Upper Basin, those extra deliveries are no longer a safe bet.

“There’s a growing recognition that even these huge reservoirs aren’t sufficient to keep the water supply sustainable anymore,” says Castle.

For the three Lower Basin states — California, Arizona and Nevada — that rely heavily on Lake Mead, the situation is particularly urgent. For the last several years, Mead has hovered around 1,075 feet above sea level, the point at which harsh water rationing measures kicks in. And if conditions in the reservoir continue to worsen, the Interior Department could even take control of water allocation from Lake Mead.

Eric Baker

So, with the threat of a federal takeover looming, last summer, water policy leaders in the Lower Basin states, along with the Bureau of Reclamation, the reservoir's operator, began meeting to discuss ways they can jointly boost water levels in Lake Mead. Some of the details are now available and indicate that all three states are now willing to accept additional water cuts from the reservoir on top of the cuts that they previously agreed to make in 2007.

Those measures follow a set of federal guidelines adopted nine years ago to manage water deliveries from Lake Mead given the likelihood of future shortages. The guidelines established a series of thresholds for the reservoir’s water levels that would trigger increasingly severe cutbacks for the Lower Basin states. At the time they were negotiated, few people anticipated that the drought would last as long as it has, but as Lake Mead inched closer to the critical 1,075 mark, water managers in the Lower Basin realized that the existing guidelines were not enough to prevent an eventual shortage.

While the terms of the new agreement between California, Arizona, and Nevada are still being negotiated, a few details have emerged. For starters, the Bureau of Reclamation has pledged to cut 100,000 acre-feet annually through efficiency measures such as lining irrigation canals to prevent seepage, or possibly by re-opening the long-shuttered Yuma Desalination Plant.

The three states' willingness to collectively ration their water use would have been unthinkable just a few decades ago when states fought each other in court to win as much water from the Colorado River. The cooperation is a nod to how new climate realities are re-shaping old water politics in the West. Take California, for instance. Legally, the state could hold onto every drop until Lake Mead is nearly down to mud, since the 1968 law that authorized the Central Arizona Project’s construction gave California highest priority water rights to the Colorado River. But at that point, says Castle, they’re just as impacted as everyone else.

Other collaborative agreements to reduce the strain on the Colorado River include a 2014 Memorandum of Understanding between the big water providers in the Lower Basin states, the Bureau of Reclamation, and the Central Arizona Project, pledging “best efforts” to conserve 40,000 acre feet in Lake Mead. In 2014, major municipal water providers in Arizona, California, Nevada and Colorado also agreed to fund new water conservation projects through a pilot initiative called the Colorado River System Conservation program.

For the Lower Basin especially, the negotiations are necessary to avoid the potential federal takeover, says Tom Buschatzke, the director of the Arizona Department of Water Resources. Although the Secretary of the Interior, Sally Jewell, has not voiced any immediate plans to that effect, in the past, she has made public statements on the matter.

For Buschatzke, the threat is clear: “She’ll take action if we don’t collaborate,” he says.

Here are the cuts states could face:

Arizona would lose 512,000 acre-feet of its total 2.8 million acre-feet per year allotment if Lake Mead dips below the 1,075 feet threshold. That’s 192,000 acre-feet more than the 320,000 acre-feet it had previously agreed to cut under the 2007 guidelines. Further cuts occur if the reservoir continues to drop. In another unprecedented move, Arizona water officials are talking of trying to spread cuts across all sectors of the state’s economy that rely on CAP water for drinking and irrigation — cities, farms, industries, Indian tribes and others  instead of letting only farmers take the brunt of the cuts, as dictated by their junior water rights.

California 

Thanks to the 1968 law that authorized CAP’s construction, California’s 4.4 million acre feet allotment is shielded from most of the cuts should a shortage on Lake Mead be declared. But as part of the new negotiations, the state has volunteered to cut its water use from Lake Mead by 200,000 acre feet if the reservoir’s levels fall below 1,045 feet and up to 350,000 acre-feet if levels sink to 1,030 feet.

Nevada 

The state with the smallest allotment of Colorado River water, Nevada would take a much smaller share of the cuts — 8,000 acre-feet if Mead drops below 1,045 feet and 10,000 acre-feet after that — because it has the right to only 300,000 acre-feet.

Lake Mead with its trademark "bathtub ring," a sign of how much water levels in the country's largest reservoir have dropped in recent decades. Officials in the three Lower Basin States are jointly planning new cuts in their water use from the reservoir to help stop Lake Mead from drying up.
Flickr user Harshil Shah

According to Buschatzke, the three states anticipate finalizing the agreement by early this fall, at which point negotiators will begin working the new measures into law. Those changes in law will likely not happen before 2017.

For Castle, the discussions are part of a new era in water politics — one that looks increasingly collaborative. “We haven’t seen states versus state or state versus feds for a long time,” she says. “There’s a recognition that litigation is failure, that we need to come together and make things work.”

Sarah Tory is a correspondent for HCN. 

High Country News Classifieds
  • EXECUTIVE DIRECTOR, BADLANDS CONSERVATION ALLIANCE
    The Executive Director of the Badlands Conservation Alliance (BCA) builds and leads a premiere North Dakota advocacy group that serves to protect the ecology of...
  • CLIMATE FELLOW
    Application deadline: Monday, March 6th, 2023, at 5 p.m. MST. Anticipated start date: May 15, 2023 About the position Are you ready to craft an...
  • RISING LEADERS MANAGER
    Application deadline: Monday, March 27, 2023, at 5 p.m. MST Anticipated start date: May 22 or May 30, 2023 About the position Do you want...
  • SENIOR SPECIALIST, LANDSCAPE CONNECTIVITY YELLOWSTONE TO YUKON CONSERVATION INITIATIVE
    About the Organization Yellowstone to Yukon Conservation Initiative (Y2Y) is a joint Canada-U.S. not-for-profit organization with a mission to connect and protect wildlife habitat from...
  • VIRGINIA SPENCER DAVIS FELLOWSHIP
    High Country News, an award-winning magazine covering the communities and environment of the Western United States, seeks applicants for a Virginia Spencer Davis fellow. The...
  • GRANTS MANAGER
    The Grants Manager is a passionate information manager, fundraiser, and communicator versed in government and foundation grant and cooperative agreement writing and management, specifically to...
  • COMMUNICATIONS DIRECTOR
    The Communications Director is a passionate communications professional versed in conservation and regenerative agriculture, as well as nonprofit communications and data management across several program...
  • EDUCATION AND OUTREACH PROGRAM DIRECTOR
    The Education and Outreach Director is a people-oriented facilitator, communications wizard, and team leader who has experience designing, managing, and fundraising for land based educational...
  • ADOBE HOME FOR SALE
    Restored traditional adobe home in No. New Mexico on 1+ acre site, irrigation water, separate large shop/studio. Please email for photos/full description.
  • HIGH COUNTRY NEWS EDITORIAL INTERNS
    High Country News, an award-winning magazine covering the communities and environment of the Western United States, is looking for its next cohort of editorial interns....
  • DEVELOPMENT PROGRAM SPECIALIST
    hat We Can Achieve Together: If you are a detailed individual that takes pride in your accuracy, this position may be the perfect opportunity for...
  • EXECUTIVE DIRECTOR - LEMHI COUNTY HUMANE SOCIETY (SALMON, IDAHO)
    Are you ready to take the reins at Lemhi County Humane Society and make a difference in the lives of countless animals? We are seeking...
  • ENVIRONMENTAL AND CONSTRUCTION GEOPHYSICS
    We characterize contaminated sites, identify buried drums, tanks, debris and also locate groundwater.
  • DEVELOPMENT DIRECTOR
    The Clark Fork Coalition (CFC) seeks an enthusiastic Development Director to lead all fundraising activities in support of our mission to protect and restore the...
  • MATADOR RANCH MANAGER
    The Matador Ranch Manager directs operations, communication, and maintenance for TNC Montana's Matador Ranch preserve with a focus on ecological management and restoration, grazing management,...
  • WESTERN NATIVE SEED
    Native plant seeds for the Western US. Trees, shrubs, grasses, wildflowers and regional mixes. Call or email for free price list. 719-942-3935. [email protected] or visit...
  • CEO BUFFALO NATIONS GRASSLANDS ALLIANCE
    Chief Executive Officer, Remote Exempt position for Buffalo Nations Grasslands Alliance is responsible for the planning and organization of BNGA's day-to-day operations
  • "PROFILES IN COURAGE: STANDING AGAINST THE WYOMING WIND"
    13 stories of extraordinary courage including HCN founder Tom Bell, PRBRC director Lynn Dickey, Liz Cheney, People of Heart Mountain, the Wind River Indian Reservation...
  • GRANT WRITER
    JOB DESCRIPTION: This Work involves the responsibility of conducting research in the procurement of Federal, State, County, and private grant funding. Additional responsibilities include identifying...
  • ASPIRE COLORADO SUSTAINABLE BODY AND HOME CARE PRODUCTS
    Go Bulk! Go Natural! Our products are better for you and better for the environment. Say no to single-use plastic. Made in U.S.A., by a...