Six western states that rely on water from the Colorado River have agreed on a model to dramatically cut water use in the basin, months after the federal government called for action and an initial deadline passed.
California – with the largest allocation of water from the river – is the lone holdout. Officials said the state would release its own plan.
The Colorado River and its tributaries pass through seven states and into Mexico, serving 40 million people and a $5bn-a-year agricultural industry. Some of the largest cities in the country, including Los Angeles, Phoenix, Denver and Las Vegas, two Mexican states, Native American tribes and others depend on the river, which has been severely stressed by drought, demand and overuse.
States missed a mid-August deadline to heed the US Bureau of Reclamation’s call to propose ways to conserve 2m to 4m acre-feet of water. They regrouped to reach consensus by the end of January to fold into a larger proposal Reclamation has in the works.
Arizona, Nevada, New Mexico, Colorado, Utah and Wyoming sent a letter on Monday to Reclamation, which operates the major dams in the river system, to outline an alternative that builds on existing guidelines, deepens water cuts and factors in water that is lost through evaporation and transportation.
Those states propose raising the levels where water reductions would be triggered at Lake Mead and Lake Powell, which are barometers of the river’s health. The model creates more of a protective buffer for both reservoirs – the largest built in the US. It also seeks to fix water accounting and ensure that any water the Lower Basin states intentionally stored in Lake Mead is available for future use.
The modeling would result in about 2m acre-feet of cuts in the Lower Basin, with smaller reductions in the Upper Basin. Mexico and California are factored into the equations, but neither signed on to Monday’s letter.
John Entsminger, general manager of the Southern Nevada Water Authority, said all states have been negotiating in good faith. “I don’t view not having unanimity at one step in that process to be a failure,” he said late on Monday. “I think all seven states are still committed to working together.”
California released a proposal last October to cut 400,000 acre-feet. An acre-foot is enough water to supply two to three US households for a year.
JB Hamby, chair of the Colorado River Board of California, said California will submit a model for water reductions in the basin that is practical, based on voluntary action and aligns with law governing the river and the hierarchy of water rights.
“California remains focused on practical solutions that can be implemented now to protect volumes of water in storage without driving conflict and litigation,” he said in a statement o Monday.
Nothing will happen immediately with the consensus reached among the six states. However, not reaching a consensus carried the risk of having the federal government alone determine how to eventually impose cuts.
By not signing on, California does not avoid that risk.
The US Bureau of Reclamation will consider the six states’ agreement as part of a larger proposal to revise how it operates Glen Canyon and Hoover Dams – behemoth power producers on the Colorado River. The reservoirs behind the dams – Lake Powell and Lake Mead – have reached historic lows amid a more than two-decade-long drought and climate change.
Without California’s participation, the six states’ proposal can only go so far to meet the hydrological realities of the river. Water managers in the Lower Basin say the scale of conservation Reclamation is seeking cannot be met without California, tribes and farmers who draw directly from the Colorado River.
Also unclear is how much Mexico eventually will contribute to the savings. In the best water years, Mexico receives its full allocation of 1.5m acre-feet under a treaty reached with the US in 1944.