Click the link to read the article on the KVNF website (Brody Wilson):
April 29, 2025
The Colorado River is the lifeblood of the American Southwest. Forty million people depend on it — not just here in Colorado, but in cities like Phoenix, Las Vegas, and Los Angeles.
Here on the Western Slope, we don’t always feel directly connected to the Colorado River. After all, we live in the Gunnison Basin — a different watershed, right?
Not quite. The Gunnison River contributes about 17% of the Colorado River’s total annual flow. So any decision made about the Colorado River’s future directly affects us — how much water we can use, when, and for what purpose. For decades, the river has been in a slow-moving crisis. Climate change, explosive population growth, and overallocation have pushed the system to the brink. In 2022, the river’s two main reservoirs — Lake Powell and Lake Mead — reached such low levels that hydropower turbines at Glen Canyon Dam were nearly shut down and dam operators were near “dead-pool” where water would no longer be able to pass through the dam. But today, nearly three years later, the system isn’t bouncing back. Andy Mueller, General Manager of the Colorado River District, has a blunt message: the Colorado River is carrying less water than it used to, and if we don’t change course, the future of agriculture, recreation, and the our way of life across the Western Slope could be at risk.
“The average temperature in March has gone up 4.2 degrees Fahrenheit,” Mueller told the crowd in Ridgway. “And for every 1 degree of warming, streamflow drops by 3 to 5 percent. We’re looking at a 20% decline right here in the Uncompahgre Valley over the last 125 years.”
These trends are part of a long-term warming and drying pattern. Less snow is falling, and what does fall melts earlier. That means less water reaches our rivers — and more of it is lost to evaporation or absorbed by plants growing in longer, hotter seasons.
In 1922, Federal and State representatives met for the Colorado River Compact Commission in Santa Fe, New Mexico. Among the attendees were Arthur P. Davis, Director of Reclamation Service, and Herbert Hoover, who at the time, was the Secretary of Commerce. Photo taken November 24, 1922. USBR photo.
To understand what’s happening now, you have to go back to 1922. That’s when the seven states in the Colorado River Basin signed a compact to divide the river’s water. Colorado, New Mexico, Utah, and Wyoming became the “Upper Basin.” California, Arizona, and Nevada formed the “Lower Basin.” Each side was promised 7.5 million acre-feet of water per year. But there was a problem: the river wasn’t carrying that much water — and certainly doesn’t now. For decades, this over-allocation was masked by big reservoirs like Lake Powell and Lake Mead. But as the drought continues, those buffers have disappeared. In 2007, the states and federal government adopted a temporary fix: interim guidelines to manage the system during dry years. Those guidelines are set to expire in 2026. New rules must be negotiated now — and the clock is ticking.
“There’s a lot of confusion out there,” Mueller said. “People talk about renegotiating the Compact — but that’s not what’s happening. The Compact isn’t being touched. What’s being negotiated are the guidelines for how Powell and Mead are operated — especially in times of shortage.”
Click the link to read the paper on the InkStain.net website (Kathryn Sorensen, Sarah Porter, Eric Kuhn, and Cynthia Campbell). Here’s an excerpt:
April 18, 2025
Conserving water now in reservoir savings banks, as a hedge against future risks associated with drought and declining flows, has emerged as one of the central tools for managing the Colorado River. The Lower Basin “Intentionally Created Surplus” program, created in the 2007 Interim Guidelines, has shown the idea’s promise and given the basin nearly two decades to learn the strengths and weaknesses of the approach. With tweaks to allow similar efforts in the Upper Basin and other modifications based on what we have learned about the current ICS approach, such “Floating Pools” are one of the key tools being considered as negotiators try to thread the needle of a seven-state agreement for post-2026 Colorado River management. Done properly, they have the potential to finesse the states’ disagreement over the terms of the 1922 Colorado River Compact in a way that could avoid potentially disruptive litigation. But getting the details right will be crucial to the development of an enduring bargain that can help the basin avoid the risk of interstate litigation.
Context
Negotiations over post-2026 operating rules for Lakes Powell and Mead are a proxy battle over whether the 1922 Compact acts as a limitation on yet-to-be used water in the Upper Division States or as a cut to existing water uses in the Lower Division States. Much of the conflict focuses on Article III(d) of the Colorado Compact, which states, “The states of the Upper Division will not cause the flow of the river at Lee Ferry to be depleted below an aggregate of 75,000,000 acre-feet for any period of ten consecutive years. . .”
The Upper Division States have a fundamentally different interpretation of their Compact obligations at Lee Ferry than the Lower Division States. Clearly, the best-case scenario for the Lower Division States, especially in Central Arizona, is a court decision that confirms the Upper Division States have a compact obligation to not deplete the flow of the river below 75 million acre-feet every ten years plus ½ of the annual delivery to Mexico under the 1944 Treaty, approximately 82 million acre-feet every ten years. This outcome would mostly stabilize the water supply available to the Lower Division States and likely limit consumptive uses in the Upper Division States to about the same or a little less water than they are currently using, approximately 4 million acre-feet per year. If the high court rules instead that the Upper Division States have a non-depletion obligation, and that consumptive uses in the Upper Division States are not the “cause” of inadequate flows needed to deliver 8.23 million acre-feet to the Lower Division States and Mexico, the result in a declining river system is a cut, potentially even to zero, for water delivered via the Central Arizona Project (CAP) into the Sun Corridor from Phoenix to Tucson and potential cuts to water-right holders in Western Arizona, Southern California and Nevada who are next on the chopping block.
Distilled to its core, here is the question before us: in a declining river system and in the absence of an agreement among the Divisions, does the operation of Article III(d) of the Compact result in a limitation on future new uses in the Upper Division States or an elimination to existing ones in the Lower Division States?
Map of the Colorado River drainage basin, created using USGS data. By Shannon1 Creative Commons Attribution-Share Alike 4.0
Udall/Overpeck 4-panel Figure Colorado River temperature/precipitation/natural flows with trend. Lake Mead and Lake Powell storage. Updated through Water Year 2024. Credit: Brad Udall
It’s easy to take for granted the accounting innovations in the Colorado River governance regime’s 2007 guidelines, which have governed river management and the upstream-downstream relationships between the upper and lower basins. “Intentionally Created Surplus” (ICS) is now part of the lexicon, and the idea behind it shows enough promise that it’s at the heart of the current negotiations over the post-’07 guidelines management of the river.
But we need to be careful about the lessons that we learn, and the details of how we implement the successor to ICS. How should the successor to ICS related to action levels for reservoir management? How do we ensure that water in ICS-like accounting pools is really conserved water, part of a sincere effort to reduce basin consumptive use?
Those questions are at the heart of the argument in Floating Pools & Grand Bargains, a new white paper by Kathryn Sorensen from Arizona State University and a group of colleagues, including Eric Kuhn:
As Save the Colorado and Denver Water prepare to face off in a federal courtroom Tuesday, water officials across the state are watching the Gross Dam expansion case closely for its environmental impact and its affect on water projects across the West.
Kirk Klancke, a long-time Grand County environmentalist and president of the Colorado River Headwaters Chapter of Trout Unlimited, said a decision that shuts down the $531 million water project, could also shut down 12 years of work on the Fraser River and its tributaries.
Denver Water is one of 18 partners who signed the Colorado River Cooperative Agreement in 2013, ushering in a new era of cooperation between the utility and West Slope stakeholders, all with the vested interest in protecting watersheds in the Colorado River Basin. As part of that agreement, a process called “Learning by Doing” was created, which has helped the utility stay better connected on river conditions in Grand County. The partnership is a collection of East and West Slope water stakeholders who help identify and find solutions to water issues in Grand County. “Denver Water has been part of Grand County for over 100 years, and we understand the impact our diversions have on the rivers and streams,” said Rachel Badger, environmental planning manager at Denver Water. “Our goal is to manage our water resources as efficiently as possible and be good stewards of the water — and Learning By Doing helps us do that.”
Here’s why: Denver Water owns much of the Fraser with water rights dating back more than 100 years. And it is that water that has historically been piped through the Moffat Tunnel near Rollinsville to fill the existing Gross Reservoir. The new water for the expanded reservoir will come largely from that river as well.
After what’s known as the 2013 Colorado River Cooperative Agreement was signed, Denver Water agreed to conduct extensive restoration work on the river in exchange for being able to raise Gross Dam and bring more water from the Fraser River over to the Front Range.
Klancke said the heavily diverted, scenic waterway would suffer if the deal falls apart. “To dissolve that partnership will be the death of the Fraser River,” he said.
Under the terms of the Colorado River Cooperative Agreement, the work on the Fraser River can only be finalized if the Gross Dam expansion proceeds.
On the upside though, Klancke said, if a new environmental settlement were reached, it could mean more money and more work to restore South Boulder Creek on the other side of the Continental Divide. The creek carries that Fraser River water from the reservoir to Denver Water’s northern storage system.
“I would love to see Denver put a whole bunch of money into South Boulder Creek,” Klancke said.
Gary Wockner, the head of Save The Colorado, disputes the notion that the case could harm environmental work already underway in Grand County.
“We are not causing environmental damage,” he said. “If Denver Water chooses to stop, that’s their choice. That’s on their shoulders. Not ours.”
For its part, Denver says it hopes to continue the Grand County work, but that the terms of the Fraser River agreement are all based on the successful completion of the Gross Dam expansion.
The agency also says it has already set aside $30 million to help offset any environmental harm caused by the massive construction project, including providing 5,000 acre-feet of water to improve streamflows along a 17-mile stretch of South Boulder Creek. An acre-foot of water equals nearly 326,000 gallons, enough water to serve two to four urban households for one year.
Roller-compacted concrete will be placed on top of the existing dam to raise it to a new height of 471 feet. A total of 118 new steps will make up the new dam. Image credit: Denver Water.
Denver Water first moved to raise Gross Dam more than 20 years ago when it began designing the expansion and seeking the necessary federal and state permits.
After years of engineering, studies and federal and state analyses, construction began in 2022. It has involved taking apart a portion of the original dam, built in the 1950s, and raising its height by 131 feet to nearly triple the reservoir’s storage capacity to 119,000 acre-feet from 42,000 acre-feet.
Save The Colorado has launched several unsuccessful challenges to the project, but in 2022 it won an appeal that put the legal battle back in play. Despite months of settlement talks, no agreement was reached.
Then the case took center stage again April 3, when Senior U.S. District Court Judge Christine Arguello put a temporary halt to construction of the higher dam, at Save The Colorado’s request.
Almost immediately, Denver Water filed for temporary relief from the order, saying, in part, that it would be unsafe to stop work as the incomplete concrete walls towered above Gross Reservoir.
Arguello granted that request, too, allowing Denver to continue working on the dam.
Gross Dam case spurred $100 million settlement in a different lawsuit
What happens next is anyone’s guess. Jennifer Gimbel, a water policy scholar at Colorado State University who also serves on Northern Water’s board of directors, said the case has already had an impact on a $2 billion water project to deliver water to residents of fast-growing northern Colorado. The Northern Integrated Supply Project, as it is known, also faced a legal challenge from Save The Colorado, and ultimately the water agency opted to settle the case for $100 million. The cash will help restore the Cache la Poudre River with new diversion agreements and improved streamflows, among other benefits.
Gimbel said the Gross Reservoir case was a key factor in that settlement. “Because of Denver’s troubles with Save the Colorado, Northern Water decided to resolve their lawsuit because they were worried about their own permit getting stale and because as you delay construction costs increase.”
The Gross Dam case is also noteworthy because it has stopped a major construction project already underway and may significantly change it. Judge Arguello has ordered the U.S. Corps of Engineers, the major permitting agency, to redo its original permitting work.
Denver Water General Manager Alan Salazar has said his agency would take the case to the U.S. Supreme Court, if they lose in the lower courts.
As both sides prepare for Tuesday’s hearing, the 10th Circuit Court of Appeals panel has said it will wait to see what information emerges from the Tuesday hearing before it rules on Denver Water’s appeal before the 10th Circuit, according to Denver Water General Counsel Jessica Brody. That action seeks to permanently protect what Denver believes is its right to raise Gross Dam.
Denver Water has also raised national security concerns in the case because Save The Colorado has asked and been granted the right to review construction documents on the dam project, documents that would normally be kept from public view.
In response, the judge has told participants to expect the court to be closed periodically during the hearing to address those security concerns.
