In early April, federal forecasters came out with a sobering but not surprising prediction for many Colorado River water users after a grim snowpack across much of the Colorado River basin this winter. They projected that as the snow melted and entered the Colorado River system, much less water would flow into Lake Powell this spring than is normal. The forecast expects inflows to be about 46 percent of average, one of the lowest runoffs on record.
Low runoff means that water users have less buffer room to prevent the river’s two major reservoirs from dropping below critical elevations, which would have considerable impacts on how water and hydropower are managed.
“This year we might be able to skirt by,” said James Eklund, an attorney at Squire Patton Boggs appointed by Colorado governor John Hickenlooper to represent the state’s interests on the Upper Colorado River Commission. But back-to-back years of low inflow like this year, “That’s a crisis. That’s a big problem,” he said. “That means we are going to almost certainly trigger a shortage in the Lower Basin or be below minimum power in Powell in the Upper Basin.”
The seven Colorado River states have closely watched reservoirs decline for years as the West has started what scientists view as a transition to a more arid environment. With lower runoff expected to become the “new normal,” both basins are facing two related questions: How do you boost reservoir elevations? And where is the best place to store the system’s water?
The answer for Upper Basin states is complicated, but stakeholders are facing more and more pressure to figure out a solution.
How to Make a Bank
For Lower Basin water users in California, Arizona and Nevada, the answer to the first question is easier. Because Lake Mead is upstream from its users, they can leave, or “bank,” parts of their Colorado River entitlements in the reservoir during shortages. In good years, they can make a call and get that water back.
Creating a “bank” in the Upper Basin states of Colorado, New Mexico, Utah and Wyoming is more difficult. Its major reservoir, Lake Powell, is located downstream of its users. If they conserve water to keep Lake Powell elevations high, it is lost to them forever.
Since 2009, Taylor Hawes, who runs the Nature Conservancy’s Colorado River group, has tried to fix this problem. Some progress has been made but there’s still more work.
“We’re on water time,” Hawes said. “And things move slowly.”
There’s an incentive for the Upper Basin states to keep Lake Powell from dropping too low. The Upper Basin has a legal requirement, under the 1922 Colorado River Compact, to deliver 75 million acre-feet of water to the Lower Basin over a 10-year period. If it fails to meet that obligation, its water users could face curtailment by priority.
Most users want to avoid curtailment, especially those with more junior rights, and one way of doing that is by banking enough at Lake Powell to ensure that the Upper Basin can meet its obligations even under dry conditions.
In general, water users could create banked water by paying farmers, and cities in some cases, to not use water or use less. Some ways to do that include: rotational crop fallowing; split-season deficit irrigation, whereby farmers stop irrigating part of the year; or conservation. That deferred water would then be shepherded through the Colorado River and stored in Lake Powell.
“It’s largely a question of when do we need that and how do we do that,” said Lawrence MacDonnell, an attorney who has written about this issue. “It’s a pretty substantial undertaking.”
Issues in the Upper Basin
Demand for these kinds of programs is there. From 2015 to 2017, the Upper Basin participated in a system conservation pilot program to gauge interest in a compensated program to reduce consumptive use among water users. According to a recent report, it “successfully demonstrated water user interest.”
But when asked what the issues are, MacDonnell said: “It’s a long list.”
Funding remains one significant hurdle. These programs can be expensive because you have to pay someone not to use water. Upper Basin cities might front the money, since they often have junior rights and the most to lose from curtailment, but it’s unclear how much enthusiasm there would be.
The balancing act to keep both reservoirs above the critical elevations that would trigger cutbacks got even more difficult this month after the Upper Basin states released a letter accusing an Arizona water agency, the Central Arizona Project, of manipulating Lake Mead’s elevation to take more water from Lake Powell.
On April 16, Denver Water said it would pull its funding from the system conservation pilot program unless it saw a change in behavior from the Central Arizona Project, which controls the canal that delivers Colorado River water to Phoenix, Tucson and Arizona farmers. Days later Pueblo, Colorado said it would no longer take part in a Colorado River conservation program.
Then there’s the issue of how to keep track of the water.
Some farmers worry that instead of going to Lake Powell, their water would be diverted by downstream users. To ensure that conserved water could actually be transported across state lines from the West Slope, for instance, to the reservoir without other users diverting it would likely require some changes to current laws, MacDonnell cowrote in a recent white paper.
Water users, in some cases, also face a political conundrum, Hawes said. Some water users are looking to expand their Colorado River use. It could get tricky for them to continue to push for growth and development while at the same time supporting a rotational fallowing program.
“It’s hard for them, I think, politically, to support a demand management or water banking program on one hand when they are advocating more development on the other,” Hawes said.
The most obvious issue, MacDonnell said, comes back to the second question facing both basins: Given the current rules for the river, where’s the best place to store the system water?
There is little incentive right now for the Upper Basin to leave water in Lake Powell.
Because of the guidelines, the elevation of Lake Powell determines the release to Lake Mead, the next major reservoir in the river system. If the elevation of Lake Powell is high and Lake Mead is relatively low, the rules require Powell to send “extra water” to balance the two reservoirs. This is a politically delicate topic for Upper Basin water users because they are effectively sending more water to the Lower Basin states. The worry is that more storage in Powell could put the Upper Basin in a situation where it is often giving up water. The Upper Basin would need some sort of clarification that their bank would be excluded from the reservoir elevation used to determine how much water flows out of Powell to Lake Mead.
That might be a tough sell among some Lower Basin users.
In recent weeks, concerns around the “extra water” issue have intensified. The Central Arizona Project has been more vocal about its desire to keep Lake Mead at a “sweet spot.” It says it does not want to over-conserve water in Lake Mead, lest that raise the elevation so much that the Upper Basin doesn’t send “extra water.” The Upper Basin sees this as “gaming the system” and a breach of trust. Central Arizona Project sees that as placing its water order wisely under the current rules.
Eklund, who signed the Upper Basin letter last week, disagrees with the Central Arizona Project approach of maximizing releases from Lake Powell. He said it’s best to bank water in the reservoirs.
“Some interests in the Lower Basin seem to think it’s better to take all of their water when they can get it,” he said. “That undermines the cooperation of the seven states. Doing something that is short-term gain but long-term pain is really, in our view, short-sighted, and I think there are a number of people in the Lower Basin that agree with that.”