Text Size

Site Search

To Serve and Extend

 Credit: Pete McBride

Through administrative wrangling, risk assessment and contingency planning, Colorado is working to avoid the day—or brace for its arrival—when Colorado River water comes up short.

By Caitlin Coleman

Last winter, Colorado was in the news for uttering fighting words. Headlines like “Concerns over Colorado decision to keep all its river water” ran along the TV screen. At the time, an Associated Press story used a quote from Colorado Water Conservation Board director James Eklund making it sound like Colorado was flexing its muscle to prevent Colorado River water from flowing down to drought-stricken California. That aggressive, Colorado-centric stance was never Eklund’s intention.



The Southwest is tightly bound together by the vital blue cord of the Colorado River, which links the seven states and Mexico. “We’re joined at the hip,” Eklund says. In addition to his position with the Colorado Water Conservation Board, Eklund serves as Colorado’s commissioner on the Upper Colorado River Commission. The commission, created by the 1948 Upper Colorado River Compact, consists of five commissioners, one from each of the four Upper Colorado River Division states and one appointed by the federal government. It coordinates among the Upper Division states and works with the Lower Division on concerns that involve all river users, including ways to cope with drought and low reservoir levels in Lake Mead and Lake Powell. “This is kind of one of those ‘we all hang together or we all hang separately’ deals,” says Eklund.


For most states in the Colorado River Basin, the river is so essential that to “hang separately” is not an option. “If we’re not cooperating, the negative effects could just propagate like waves and we’d all be in a difficult position,” says Eric Millis, Utah’s Upper Colorado River commissioner and director of Utah’s Division of Water Resources.


In Utah, about 20 percent of the state’s water comes from the Colorado River, while Coloradans are even more dependent: According to the Colorado Division of Water Resources, two-thirds of all water diverted in Colorado is pulled from the Colorado River and its many tributaries, which flow west from the Continental Divide that cuts through the middle of the state. The Colorado is crucial even on the state’s Eastern Slope, where transbasin diversions transport more than a half million acre-feet of Colorado River water every year across the Continental Divide to supplement native flows on the South Platte and Arkansas rivers, supporting both urban and agricultural users.


As Colorado leans vulnerably on the Colorado River, some hold out hope that the river might still provide an increment of additional water for future thirsty citizens and crops. If additional water were developed, that would shift the stakes even higher. Faced with downstream pressures and the threat of system-wide shortage, Colorado’s interest in protecting its share of Colorado River water is peaking.   


The Upper Division’s Water

As overdevelopment, climate change and drought threaten the future of the Colorado River, the Upper Division states risk being unable to meet their flow requirements at Lee Ferry, in which case the Lower Division could “call” for its missing water or pin a compact violation on the Upper Division. Although a compact curtailment isn’t an urgent threat, says Don Ostler, executive director for the Upper Colorado River Commission, avoiding one allows the upper basin states, including Colorado, to continue using water as they have, maintaining a greater degree of control over their share of the river.


If flows at Lee Ferry approach levels that would violate the compact, the Upper Colorado River Commission would manage the process, where each state within the Upper Division would likely have to curtail some or all of the water developed after the compact was signed. But, if Colorado or any other Upper Division state had used more than its apportionment during the 10-year period leading up to the violation, the 1948 Compact requires that state to “repay” water before other states in the Upper Division would have to make cuts.


When the upper basin states negotiated the 1948 Upper Colorado River Compact to split the upper basin’s Colorado River Compact apportionment among themselves, Colorado, as the state that produces the largest portion of the river’s flow, received the largest chunk: 51.75 percent of the water available to the Upper Division, or as stated by the compact, 51.75 percent of “the consumptive use per annum.” Utah got 23 percent, Wyoming 14 percent, and New Mexico 11.25 percent. This is each state’s cut after the upper portion of Arizona receives an annual allotment of 50,000 acre-feet.


Since then, the upper basin states have stayed within their apportionments, or have at least come close. According to the Bureau of Reclamation’s provisional data for 2011 and 2012, New Mexico, Utah and Wyoming all used less water than their allocated percentages. But has Colorado been overusing its share of upper basin water? “That depends on who you talk to,” Ostler says.


Westward bound, the Colorado River gathers the Blue River (right) near Kremmling, Colorado, before winding
another 1,415 miles through six downstream states and Mexico. Nearly a dozen nearby reservoirs referred to as the
Great Lakes, store water mostly for irrigating hay meadows. Many have rights established prior to the 
Colorado River Compact, making them highly coveted by those who would risk curtailment in times of 
Credit: Pete McBride

The same Reclamation data show that during those lower-flow years, Colorado was responsible for nearly 57 percent of the upper basin’s consumptive uses and losses from reservoir evaporation—potentially about 5 percent more than Colorado’s allocated share of the Upper Division’s water.


But if the river’s flow is as high as was expected by the framers of the Colorado River Compact in 1922, Colorado is entitled to use 51.75 percent of the upper basin’s minimum apportionment of 7.5 million acre-feet annually (after Arizona gets its 50,000 acre-feet)—that’s 3.8 million acre-feet of water, and Colorado has only been using 2.5 to 2.8 million acre-feet per year. Still, we rarely observe such high flows and meanwhile must continue to meet requirements to the lower basin.


While some continue to interpret the 1922 and 1948 compacts to say Colorado can legally use 51.75 percent of 7.5 million acre-feet, others believe Colorado can use 51.75 percent of 6.2 million acre-feet—that’s the number Utah uses for planning—developed by Reclamation’s hydrologic determination in 2007. Some see Colorado’s apportionment as 51.75 percent of the river’s total flow after the lower basin’s flow requirements are met. Still others believe it’s 51.75 percent of the upper basin’s actual consumptive use. “When people are saying Colorado is using over their compact apportionment, they’re making assumptions of what the available amount of water for use in the upper basin is,” Ostler says. “You may hear various views as to how much water is being used. The [Upper Colorado River] Commission has not made any determination that Colorado is in overuse of their compact apportionment.”


All interpretations are equally valid, for now. Ultimately, if there was ever a violation of the compact and litigation between states ensued, the U.S. Supreme Court would decide if the current flow obligation outlined in the compact needs to be revised to re-balance the risk that each basin shoulders. And if a water shortage materializes, is the upper basin actually dividing up 7.5 million acre-feet or a lesser amount based on availability?


“The question is ‘who bears the brunt of climate change?’” Eklund says. If streamflows continued to drop and the upper basin maintained compact compliance by meeting the non-depletion requirement at Lee Ferry, the Upper Division states would have access to significantly reduced supplies. If that non-depletion requirement wasn’t addressed, the Lower Division states could face the disadvantage, at least until the Supreme Court or the states decided if the impact of climate change should be shared. “The court would need to evaluate whether the equality we were trying to achieve in the 1922 compact is arguably undermined if the lower basin gets to keep its full allocation and we [Colorado] get 51.75 percent of only some very small fraction of the river,” Eklund says.


Ultimately, when viewing its apportionment, Colorado shares the commitment of other states to finding collaborative solutions outside of the courtroom, especially considering the risk of having narrower limitations imposed in response to a litigated compact violation.

Still, for Colorado to stay within its share—a percentage volume that’s based on a moving target—is a tricky proposition. Without knowing with certainty what the Upper Division’s total water consumption will be for the year, or the next 10 years, and without being legally compelled, Colorado isn’t yet taking any measures to make sure it’s sending the right quantity downstream, whatever that quantity may be; it tracks water diversions and consumptive uses for in-state administrative purposes and for studies assessing how much water might be available to develop in the river.


But if the time comes when the Lower Division isn’t receiving its flows, Colorado could have to repay any overages, and it’s hard to say how that would go. There aren’t rules yet that detail how water would be administered during a call on the Colorado River, nor rules to stave off such a call. That’s a sharp contrast to nearly every other river in Colorado, where, due to over-appropriation, compacts are already an integral factor guiding water administration, at least seasonally.

Preparing for the Worst Case


Rulemaking in the context of Colorado’s extensive prior appropriation system would be one way of readying to protect Colorado’s share of Colorado River water in the event of shortage—but this administrative step hasn’t been prioritized because curtailment has not yet been an imminent threat.


In the absence of such rules, and without knowing how much water will be available in the future, Colorado is playing a risky game when it makes new water management and development decisions, says Kevin McBride, a member of Colorado’s Interbasin Compact Committee and general manager of the Upper Yampa Water Conservancy District. “It’s like we’re going to Las Vegas and we all have to play this one hand, and we don’t even really know what the rules are.”


It’s also complicated, explains Colorado State Engineer Dick Wolfe, who would be responsible for making the rules, because Colorado has so many tributaries—like the Animas, the Dolores, the La Plata, the White, and the Green—that leave the state before reaching the Colorado River’s mainstem. For intrastate purposes, those tributaries have always been administered separately, but when you start administering rights on the Animas River in relation to rights on the Green, for example, you’re exploring new territory.

Besides, that’s just one way to look at it. New rules for a compact call on the Colorado could be entirely different than administering water by applying the existing prior appropriation system across the basins. It may also be possible for the State Engineer’s rulemaking to prioritize critical water uses—for example, municipal use might take priority over agricultural diversions or environmental flows—or to consider a completely different framework with legislative approval. Such a decision would be a departure from strict prior appropriation, applying the “domestic clause” in the Colorado Constitution, which says that in times of shortage, domestic water use has preference over all other uses, and agricultural water use has preference over manufacturing.


McBride suggests that each of Colorado’s Colorado River tributary basins should send a certain negotiated amount of water downstream to meet compact obligations before prior appropriation is administered across basins. From where McBride sits in the state’s relatively sparsely populated northwestern corner, it’s worrisome that the region’s future development and water use might be precluded by larger and more rapidly growing parts of the state. He invokes the 1922 compact’s spirit of equity: Favoring the state’s faster-growing basins is just what the compact attempted to avoid, but on a larger scale.


Any rules that might be established are still years out. First, the state is completing a couple of studies to inform its decision making. The first phase of the Colorado River Water Availability Study was completed for the Colorado Water Conservation Board in 2012—it generated a lot of useful data but didn’t prescribe solutions. The study’s second phase is now underway, looking at possible scenarios and discussing solutions to support development and implementation of Colorado’s Water Plan, says Ted Kowalski, chief of the CWCB’s interstate and federal section.


The CWCB is also working on a Colorado River Compact Compliance Study with the Colorado Attorney General’s Office and the Colorado Division of Water Resources to identify issues associated with administering water rights in the Colorado Basin under the terms of the compact—perhaps laying the groundwork for the State Engineer’s rulemaking by evaluating possible approaches to intrastate administration of water rights in the event of Colorado River curtailment. Kowalski expects the compliance study to wrap up in another year or two. Rulemaking in the wake of the studies’ completion, which would have to undergo a public comment process, could take at least another five years.

The Risk of Developing More

In the midst of these plans for shortage and compact violations, Colorado’s population continues to skyrocket, and some argue that there is water left to develop in the Colorado River that could help quench a growing thirst. It’s not clear how much water might be available. Colorado River Water Availability Study estimates range from zero to around 800,000 acre-feet depending on the hydrological, climatic and legal future, though the higher estimates assume a return to abnormally wet conditions on the Colorado, says Eric Kuhn, general manager of the Colorado River Water Conservation District, a regional water agency dedicated to optimizing Colorado’s share of the Colorado River through both protection mechanisms and carefully managed development.


To take advantage of what water remains, many advocate for new reservoirs to capture and store streamflows locally, both for delivery to residents and to restore flows in dry rivers late in the season. Others suggest diverting captured flows through another transbasin diversion across the Continental Divide to Colorado’s urban corridor where most of the state’s growth will occur. Such a plan could be both risky and contentious.


“With the amount [of water] we’re using today, the system is draining itself,” Kuhn says, pointing to reservoir levels that continue to fall lower. “What would happen if we were using more? It’s a little like a family budget. We’re spending too much to think it would be okay if we were to spend a lot more.”


A new transbasin diversion, says Kuhn, would also increase Colorado’s risk of violating the compact. “If we build more [transbasin diversions] and divert more, we’ll undermine the security of post-compact rights. It’s a community loss,” he says.


Risky or not, the possibility is on the table, and water experts around the state have negotiated what they call a conceptual framework, which lays a path forward for difficult discussions such as evaluating what the state would do in the case of curtailment or determining which water, if any, could be developed. The framework, though incorporated in the new state water plan, isn’t legally binding, and the next step is to actually have those discussions. “Let’s have studies and buy-in from all corners of the state and have that conversation,” Kuhn says.


Those conversations and planning aren’t limited to in-state interests—if Colorado develops more water from the Colorado River, it could affect all Upper Division and downstream states. “All of the states are interested in what each other is planning,” Millis says. “But we understand that each state has water yet to develop in the river system. We would support each other in developing [each state’s] own apportionments of the river.”


While Colorado finalizes its state water plan, Utah, the second biggest user in the Upper Division, is making plans to build a pipeline, settle Native American water rights, and construct other projects to use what it estimates to be its remaining apportionment of around 369,000 acre-feet of water. The Lake Powell Pipeline should be complete and delivering water within the next 10 years, Millis says. Although the risk of an uncertain hydrologic future is very real in Utah, Millis says the state is confident that water will be available for the planned pipeline. Besides, all risks are weighed against each other. “One of the risks you consider is, what’s the risk of doing nothing?” Millis says. Looking at the lack of water supply in southwestern Utah’s St. George area, for instance, Utah would be limiting the region’s future economic and population growth if it didn’t develop the pipeline to deliver additional water.


The nation's second-largest reservoir after Mead, Lake Powell can store up to 24.3 million acre-feet of Colorado River
water for release to the lower basin. Powell reached capacity in 1980, after fiilling for 17 years, but in October 2015
was just 51 percent full.
Credit: Pete McBride

System-Wide Connections

While uncertainty and the possibility of new water development or a transbasin diversion brings with it risks of compact violation, the physical threat, more immediate than a compliance breach, is drought and low reservoir levels in Lake Powell and Lake Mead—threats that reach beyond the protections of the Colorado River Compact. In many ways, Colorado’s ability to fully use its apportionment of the Colorado River depends on water availability throughout the entire basin.


Eklund lists what he calls a “parade of horribles” that could manifest if water levels in the reservoirs fall too low: not enough water to release for power generation and consequent loss of power revenues that are needed to fund endangered fish recovery and salinity control programs, and, most critically, not enough water to reach major metropolitan areas that depend on it. For example, if there wasn’t enough water for Las Vegas or another downstream city to serve its residents, the Upper Division may be inclined or forced to send water downstream, if possible, to prevent a human safety crisis, potentially dipping into Colorado’s water.


The Upper Colorado River Commission and the Bureau of Reclamation have been developing a contingency plan to avoid curtailment and reduce the chances of Powell dropping below critical levels. The lower basin has only one option, which it’s working toward: to use less water out of Lake Mead. The upper basin has more tools in its toolbox.

First, the commission is working to better account for upper basin water and to calculate a more accurate and timely estimate of consumptive uses in the upper basin. “If we need to react to compact conditions and low water conditions, we need quicker access to how much water is being used in the recent past,” Ostler says. He’s leading a study, which he hopes to complete in the next year, to identify the methods that upper basin states, the Bureau of Reclamation, and other experts are using to estimate and account for water use. Ultimately he wants to see each of the states and Reclamation using a consistent methodology. “If and when we have to use that information for a compact issue, the amount of use and procedures will not be a question,” Ostler says.

The commission has also been working with all upper basin states on local projects like cloud seeding and invasive plant removal that have been shown to boost the system’s water supply, as well as studying the operation of the federal Colorado River Storage Project reservoirs upstream from Lake Powell, including Blue Mesa, Flaming Gorge and Navajo. Those reservoirs are primarily system-wide storage reservoirs, like smaller extensions of Lake Powell. When Powell is low, some of those reservoirs higher in the system could still be holding enough water to reduce the risk of compact issues. “If we got into a really catastrophic situation, we could send floods of water down from those reservoirs,” Eklund says, explaining that the commission has worked to be able to make small strategic releases without causing problems for the people or environment that depend on the system below them. Exactly how much water would be needed, and by when, is still being studied. “We’re moving on all fronts to make sure we’re as knowledgeable as we can be about the reservoirs and make sure we know what we can influence,” Eklund says.


The next piece is managing and reducing the entire basin’s demand by encouraging the states to use less water. Demand management has been successfully practiced in all the basin states to increase crop yields or support growing urban populations using the same amount of water or even slightly less. However, much remains to be achieved when it comes to reducing actual consumption at a significant scale, as well as determining how water use reductions in the upper basin could “move the needle” by actually appearing in Lake Powell.


“Should we face a drought like this or a worse drought in the future, it’s much better to be developing these kinds of tools when we’re not in the throes of crisis,” Kowalski says. “Which we’re doing and we’re proud we’re doing, so we’re ready should a crisis hit.”


Gov. Jerry Brown of California took demand management into his own hands in spring 2015, ordering cities and towns across California to cut water use by 25 percent as part of a set of mandatory drought restrictions, the first in the state’s history. “It’s a different world,” Brown said. “We have to act differently.” And so they have, regularly exceeding the 25 percent goal for the first couple of months.


There are no laws that lay out the rules for such an order in Colorado, but anything could happen. “If your [water] system that you depend on got 5 percent of average snowpack, all bets are off,” Eklund says. “California ended its [2015] water year at only 5 percent of average. If it can happen in California, I think we’re pretty damn naive if we think it can’t happen in Colorado.”


CO River Report & Webinar


On April 14, CFWE, in partnership with CoBank, hosted a webinar "Managing the Colorado River in the 21st Century." Access a recording of the webinar here or download a PDF of the presentations here.


A report on the Colorado River Basin released in partnership between CFWE and CoBank's Knowledge Exchange Division is available to read and download here

1750 Humboldt Street, Suite 200
Denver, CO 80218