Arizona prepares for water cutbacks
Colorado River nears threshold for shortage
With the Colorado River’s largest reservoir just 38% full and declining toward the threshold of a first-ever shortage, Arizona water officials convened an online meeting last week to outline how the state will deal with water cutbacks, saying the reductions will be “painful” but plans are in place to lessen the blow for affected farmers next year.
Lake Mead’s decline is expected to trigger substantial reductions in water deliveries in 2022 for Arizona, Nevada and Mexico. The largest of those cuts will affect Arizona, slashing its Colorado River supplies by 512,000 acre-feet, about a fifth of its total entitlement.
While that will shrink the amount of water flowing to farmlands through the Central Arizona Project Canal, the state’s water managers said during Thursday’s meeting that they’re prepared and have plans ready to handle shortages over the next five years, even if Lake Mead continues to drop to levels that would bring larger cutbacks.
“There is a shortage, but we have a plan,” said Ted Cooke, general manager of the Central Arizona Project. “It’s called the Drought Contingency Plan. We’re implementing that plan.”
Two years ago, representatives of the seven states that depend on the Colorado met at Hoover Dam to sign the set of agreements called the Drought Contingency Plan, which laid out measures to take less water from
“This is a day we knew would come at some point.”
Ted Cooke
General manager of the Central Arizona Project
Lake Mead and share in reductions during a shortage to reduce the risks of a damaging crash.
Since then, Mead’s levels have continued to decline, even as the agreement has reduced the amounts of water to Arizona, Nevada and Mexico under an initial pre-shortage level called Tier Zero. Next year, the reservoir is set to slip into what’s called a Tier 1 shortage, which will bring the largest reductions to date.
“This is a day we knew would come at some point,” Cooke said, adding that voluntary conservation over the past few years and initial cuts under the drought deal have pushed back the onset of the shortage.
Reservoirs at historic lows
The level of Lake Mead now stands less than 5 feet above elevation 1,075 feet — the trigger point for an official shortage declaration by the federal government. That declaration is expected in August and will take effect in January.
The reservoir near Las Vegas has fallen dramatically over the past 21 years as the climate has grown warmer and drier, shrinking the flow of the river. The watershed has grown parched during one of the most extreme droughts in centuries, which many scientists describe as “aridification” worsened by the heating of the planet with climate change.
Lake Mead has dropped more than 130 feet since 2000. It is sinking toward its lowest levels since it was filled in the 1930s after the construction of Hoover Dam. The upstream reservoir Lake Powell has also fallen to just 35% of full capacity and is projected to keep declining due to meager snowpack and far-belowaverage inflows.
“Tier 1 is a painful reduction,” said Tom Buschatzke, director of the Arizona Department of Water Resources. “Arizona and its water users are taking the bulk, from a volume standpoint, of the reductions that are going to be coming.”
Arizona gets an estimated 36% of its water from the Colorado, and a large portion of it flows through the CAP Canal to cities, farms and tribal lands.
The state’s plan for managing shortages involves using deliveries of “mitigation” water to help temporarily ease the burden for some farmers and other entities, as well as payments for those who contribute water.
The state and CAP approved more than $100 million for these payments. An additional $8 million was pledged by philanthropic groups and nonprofits including the Walton Family Foundation, Environmental Defense Fund and Water Funder Initiative, with support from corporations such as Intel, Microsoft, Procter & Gamble and Cox Communications.
A large portion of the funds are going toward water contributed by the Colorado River Indian Tribes and the Gila River Indian Community.
Buschatzke and Cooke acknowledged that the tribes played vital roles.
“I want to emphasize the great sacrifice that was made by these tribes,” Cooke said, adding that they agreed to contribute water they had been using for other purposes.
Planned pain, sudden pain
The cuts in 2022 will reduce the Central Arizona Project’s water supply by nearly a third and shrink the amount flowing through the CAP Canal to farmlands in Pinal County that produce cotton, hay and other crops.
The state’s plan called for replacing a portion of that eliminated Colorado River water by enabling Pinal irrigation districts to pump an additional quantity of groundwater. Even that groundwater won’t fully make up for the cuts. Growers have said they may have to stop irrigating about a third of the area’s farmlands, leaving them dry and fallow.
Farmers in Pinal County hold the lowest priority for water from the CAP. Under a shortage, they’re in line to lose all that water. But the state’s plan will provide them with “mitigation” water in 2022 that will amount to about a third of their previous supply.
“This is a painful reduction, but fortunately, because of mitigation, it’s not going to be a full reduction right away,” Cooke said. The plan that’s being implemented, he said, is to “share resources to reduce the pain of the Tier 1 reductions.”
More than 600 people listened to the online briefing. During a press conference afterward, Cooke and Buschatzke were asked about their frequent use of the word “pain” and what they meant by it.
“It is a loss of a supply that we have been accustomed to up to this point, certain water users have, and they’re no longer going to have that,” Cooke said. “And there is some temporary partial mitigation … to soften the amount of pain that will be inflicted by sharing that with other people over time. But it does not reduce, it doesn’t make the pain go away entirely. It just mitigates it.”
With the state’s plan, the cuts are spelled out far in advance, so everybody knows what’s going to happen, Cooke said. Even though the consequences are inevitable, he said, there is a stark difference between planned pain and unexpected, sudden pain. Cooke likened it to the difference between getting injured in an accident and scheduling an elective surgery.
“The one is planned, it’s with foresight, you prepare for it. And the other one is unexpected and sudden, and you don’t have any time to prepare for it and you just live with the consequences,” Cooke said.
Over the next couple of months, Cooke said there will be meetings to make sure all the parties in Arizona are prepared to implement the state’s plan.
Nevada is also taking less water under the deal, while California agreed to participate at lower shortage levels if the reservoir continues to drop. Mexico is contributing under a separate deal by leaving some of its supplies in Lake Mead.
The effects of climate change
With the threshold of an official shortage nearing, there has been debate about how radically and quickly the management of the river will need to change in the coming years.
A growing body of scientific research has shown that the Colorado River is sensitive to rising temperatures as the planet heats up with the burning of fossil fuels.
In one 2018 study, researchers found that about half the trend of decreasing runoff in the Upper Colorado River Basin since 2000 was the result of unprecedented warming. In other research, scientists estimated the river could lose roughly one-fourth of its flow by 2050 as temperatures continue to rise.
In a report published in February by Utah State University’s Center for Colorado River Studies, researchers warned that a “gradual and incremental approach to adaptation” is unlikely to meet the river’s challenges in the future. They pointed out that flows from 2000 through 2018 were about 18% less than the average during the 20th century, saying “this downward trend is likely to continue” as temperatures rise with climate change.
Buschatzke and Cooke said the state’s water agencies will consider a range of scenarios as they begin to develop proposals for managing shortages after 2026, when the existing rules are set to expire.
In the meantime, they said, the Drought Contingency Plan lays out a schedule of progressively larger cuts and other measures if Lake Mead continues to decline. They presented a table showing how the water reductions for each of the three Lower Basin states — Arizona, Nevada and California — increase as Lake Mead declines to lower shortage levels.
“California will join in reductions beginning at elevation 1,045 (feet). I hope to God we never get there, but if we do, California will join us,” Cooke said. “Those types of possibilities are baked into the plan.”
The three-state Lower Basin deal also includes another provision aimed at guarding against the risk of Lake Mead falling to critically low levels below 1,020 feet. If the federal government’s two-year projections at any point show risks of Mead declining below 1,030 feet, the agreement says the states and the Interior secretary “shall consult and determine what additional measures will be taken.”
“That’s a very important adaptive management provision,” Buschatzke said. “Hopefully that will not happen, but it could.”
Scientists say much of the West has been in a two-decade “megadrought” worsened by climate change. But even before the long dry spell, the Colorado River was severely overallocated. The 1922 Colorado River Compact and subsequent agreements have long allocated much more water than is available.
Most of the river’s delta in Mexico was transformed into a dusty stretch of desert decades ago, leaving only a smattering of natural wetlands.
Some researchers have suggested that with dry conditions intensifying in the watershed, the region’s water managers shouldn’t wait until 2026 to make more substantial changes to the rules. When asked about that perspective, Buschatzke said he doesn’t believe “we need to add another layer to the Drought Contingency Plan” because it includes built-in measures to adapt if necessary.
“We’re constantly monitoring this. We’re not going to get caught short and somehow we don’t have time to take actions that we need to take,” Buschatzke said.
‘Pretty scary’ scenarios
The water supplies of Arizona’s cities are protected from cuts under the state’s plan in a first-level shortage.
When asked about conservation measures, Buschatzke made a distinction between long-term water-saving improvements and sudden water restrictions.
“You’re not going to see a request for people in their homes to only shower twice a week. We’re not in that situation,” Buschatzke said. “This is not a crisis at that level. We’ve been planning for this for years and doing conservation for years.”
The state’s 1980 groundwater management law laid out requirements for conservation in urban areas through a series of local plans. Water suppliers are given conservation requirements, and it’s up to them to determine how they meet them.
“There may be some cities who during the shortage decide, you know, we want to start preparing. The drought might last for another 20 years,” Buschatzke said. “It’s up to the cities, though, to put into place those types of homeowner restrictions.”
While working on the latest management plans, officials from the Department of Water Resources also held a virtual meeting last week with representatives of golf courses, Buschatzke said, to discuss conservation. They talked about the situation of the Colorado River, he said, and “why it’s so important that all of the sectors in Arizona continue to meet the conservation goals and requirements.”
As for Arizona’s expanding cities and suburbs, which are among the fastestgrowing in the country, Buschatzke said various factors go into discussions about future growth.
“I do not think that we’re at a place where what we’re seeing on the river is an automatic trigger to say there’s no more growth in central Arizona,” he said.
While preparing for next year’s cuts, water officials also plan to hold more meetings of the state-appointed Arizona Reconsultation Committee to discuss proposals for post-2026 shortagesharing rules, which will be negotiated among the states.
Buschatzke has said a central aim is to plan for a drier future with climate change.
Rhett Larson, a water law professor at Arizona State University, said he thinks the Southwest is well prepared for the coming shortage, but the potential effects of the warming climate will be tougher.
“I am very hopeful that the Drought Contingency Plan and whatever happens after 2026 will keep us above extreme shortage and above ‘dead pool.’ I actually think we have a good chance at it,” Larson said, referring to critically low reservoir levels at which Hoover Dam would no longer be able to generate electricity.
He also said, however, that models showing the effects of climate change in the Colorado River Basin point to some “pretty scary” scenarios in which reservoirs drop to extremely low levels. Preparing for those dire scenarios, he said, will require more than simply renewing the sorts of measures adopted so far.
“I’m pessimistic about climate change,” Larson said. “The modeling with the river is concerning enough that I think we need to be more ambitious, and we need to be more creative than simply re-upping.”
As for Lake Mead and the power-generating role of Hoover Dam, he said, “it’s possible we might have to redesign the outfalls to find ways to tap into scarily low levels of the reservoir.”
Ian James covers water, climate change and the environment for The Arizona Republic. Send him story tips, comments and questions at ian.james@ arizonarepublic.com and follow him on Twitter at @ByIanJames.
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