#ColoradoRiver drought study advances as participants call for fairness between cities, ranches — @WaterEdCO #COriver #aridification

Lake Powell would become home to a special 500,000 acre foot drought pool if Colorado, Wyoming, Utah and New Mexico agree to save enough water to fill it. Credit: Creative Commons

From Water Education Colorado (Jerd Smith):

If Colorado decides to join in an historic Colorado River drought protection effort, one that would require setting aside as much as 500,000 acre-feet of water in Lake Powell, can it find a fair way to get the work done? A way that won’t cripple farm economies and one which ensures Front Range cities bear their share of the burden?

That was one of the key questions more than 100 people, citizen volunteers and water managers, addressed last week as part of a two-day meeting in Denver to continue exploring whether the state should participate in the effort. The Lake Powell drought pool, authorized by Congress last year as part of the Colorado River Drought Contingency Plan, would help protect Coloradans if the Colorado River, at some point in the future, hits a crisis point, triggering mandatory cutbacks.

But finding ways to set aside that much water, the equivalent of what roughly 1 million people use in a year at home, is a complex proposition. The voluntary program, if created, would pay water users who agree to participate. And it would mean farmers fallowing fields in order to send their water downstream and cities convincing their customers to do with less water in order to do the same. The concept has been dubbed “demand management.”

Among the key issues discussed at the joint Interbasin Compact Committee and demand management work group confab last week is whether there is a truly equitable way to fill the drought pool that doesn’t disproportionately impact one region or sector in the state.

In addition, a majority of participants reported that they wanted any drought plan to include environmental analyses to ensure whichever methods are selected don’t harm streams and river habitat.

Some pointed to the need to identify “tipping points” when reduced water use would create harmful economic effects in any given community, and suggested that demand management be viewed as a shared responsibility.

Flipping the narrative of shared responsibility, participants said sharing benefits equally was important as well. They want to ensure that people selected to participate would do so on a time-limited basis, so that a wide variety of entities have the opportunity to benefit from the payments coming from what is likely to be a multi-million-dollar program.

“People are starting to get it,” said Russell George. George is a former lawmaker who helped create the 15-year-old public collaborative program which facilitates and helps negotiate issues that arise among Colorado’s eight major river basins and metro area via basin roundtables. He chairs the Interbasin Compact Committee, composed of delegates from those roundtables.

“It’s understood that we have to be fair about this and we have to share [the burden] or it won’t work. I think we’re making great progress,” George said.

The Colorado River is a major source of the state’s water, with all Western Slope and roughly half of Front Range water supplies derived from its flows.

But growing populations, chronic drought and climate change pose sharp risks to the river’s ability to sustain all who depend on it. The concept behind the drought pool is to help reduce the threat of future mandatory cutbacks to Colorado water users under the terms of the 1922 Colorado River Compact.

The public demand management study process, facilitated by the Colorado Water Conservation Board, has caused concern among different user groups, including farmers. Because growers consume so much of the state’s water, they worry that they are the biggest target for water use reductions, which could directly harm their livelihoods if the program isn’t implemented carefully and on a temporary basis.

In early 2019 the seven states that comprise the Colorado River Basin—Arizona, California and Nevada in the Lower Basin, and Colorado, New Mexico, Utah and Wyoming in the Upper Basin—agreed for the first time to a series of steps, known as the Colorado River Basin Drought Contingency Plan, to help stave off a crisis on the river.

Colorado River Basin. Map credit: The Water Education Foundation

And while Lower Basin states have already begun cutting back water use in order to store more in Lake Mead, the four Upper Basin states are still studying how best to participate to shore up Lake Powell. For the drought pool program to move forward, all four states would need to agree and contribute to the pool. George pointed to Colorado as a leader among the four states, saying it would likely be responsible for contributing as much as 250,000 acre-feet to the pool.

“We appreciate the focus, dedication and collaboration of our work group members,” said CWCB Director Rebecca Mitchell in a statement. “This workshop was the next step in sharing ideas for Colorado’s water future, and positioning our state as a national leader for cooperative problem solving.”

The eight major volunteer work groups, addressing such topics as the law, the environment, agriculture and water administration, will continue meeting throughout the year, with a mid-point report based on their findings to date due out sometime this summer.

Travis Smith, a former CWCB board member from Del Norte who is now participating on the agriculture work group, said he is hopeful that the work groups will be able to come up with a plan the public will endorse. Any final plan will likely have to be approved by Colorado lawmakers.

“Coming together to address Colorado’s water future is something we’ve been practicing through the [nine river basin roundtables] for years. Will we get there? Absolutely,” Smith said.

Jerd Smith is editor of Fresh Water News. She can be reached at 720-398-6474, via email at jerd@wateredco.org or @jerd_smith.

Interview with Daryl Vigil [Ten Tribes Partnership]: ‘This system cannot be sustained’ — @HighCountryNews #ColoradoRiver #COriver #aridification

From The High Country News [March 10, 2020]: (Anna V. Smith):

The Colorado River Basin is the setting for some of the most drawn-out and complex water issues in the Western U.S. In 2019, the Colorado River Drought Contingency Plan — a water-conservation agreement between states, tribal nations and the federal government for the basin, now in its 20th year of drought — passed Congress. This year, it goes into effect.

2020 will also see the start of the renegotiation of the Colorado River Interim Guidelines. The guidelines, which regulate the flow of water to users, were created in 2007 without tribal consultation and are set to expire in 2026. The 29 tribal nations in the upper and lower basins hold some of the river’s most senior water rights and control around 20% of its annual flow. But the tribes have often been excluded from water policymaking; around a dozen have yet to quantify their water rights, while others have yet to make full use of them. Most of the tribal nations anticipate fully developing their established water rights by 2040 — whether for agriculture, development, leasing or other uses. Drought and climate change are still causing shortages and uncertainty, however. Already, the Colorado River has dropped by about 20%; by the end of this century, it could drop by more than half.

Daryl Vigil, water administrator for the Jicarilla Apache Nation, has pushed for increased tribal participation in Colorado River renegotiation discussions. Courtesy of Bob Conrad via The High Country News

High Country News spoke with Daryl Vigil (Jicarilla Apache, Jemez Pueblo and Zia Pueblo), water administrator for the Jicarilla Apache Nation. Vigil, the interim executive director of the Ten Tribes Partnership, helped co-facilitate the Water and Tribes Initiative, coalitions focused on getting increased tribal participation on Colorado River discussions. Those efforts are critical, Vigil says, “because left to the states and the federal government, they’ve already proven that they will leave us out every time.”

HCN and Vigil spoke about “the law of the river” — the colloquial term for the roughly 100 years of court cases, treaties, agreements and water settlements that govern the Colorado — as well as tribal consultation and climate change.

This interview has been edited and condensed for length and clarity.

High Country News: Sometimes it can be hard to really understand the core value of water, because it gets so caught up in things like policies and laws and bureaucratic language. Could you boil it down a bit and explain, at the core, what’s so important about this?

Daryl Vigil: Through the Water and Tribes Initiative (in 2018), we did over a hundred interviews of all the major stakeholders in the basin: states, water providers, tribes, NGOs, conservation groups. And it was pretty amazing, to find out that when you talk to all these folks, almost universally they’re all committed; they have a personal relationship to the river as a living entity that needs to be sustained. And so there’s two different mindsets looking at ’07 guidelines and some of the policy that’s been created around the river. One really looks at the Colorado River as a plumbing system, getting water to people who need it, versus the other end of the spectrum — when you start to look at tribes and others who have similar values, who look at it as a living entity, who look at it as an entity that provides life. And so we started to try to articulate traditional, cultural values and integrate that into current policy so that people can understand. Because we know most people want to see a healthy, sustainable Colorado River, but they also have their constituencies that they protect. And so, how is it that we bridge that divide? Because people really do care about the basin, and they really do want healthy environments and healthy ecosystems. And so that’s proven part of the conversation that we were having — that the next set of guidelines absolutely needs to be able to capture not only the water-delivery issues that already are at the forefront, but really start to address the cultural, environmental, traditional values of the Colorado River and integrate that into the next set of planning. Because if we don’t, this system cannot be sustained.

HCN: How does climate change figure into the discussion?

DV: We’re already seeing the impacts. And I think that’s something that absolutely has to be considered in the planning of the future, because right now — with 41 million people in the basin — as of 2010, the imbalance between supply and demand is already a million acre-feet. It’s projected, according to the basin study, to be 3 million acre-feet by 2060. We continue to act surprised when something new comes about in terms of a fire or a flood or an incredible drought. We’re making an impact on this planet, and it’s not a good one. That’s where, with the Ten Tribes Partnership, (we’re) really trying to make sure that we integrate those traditional, cultural values and spiritual values that the tribes have for the river as we move forward. Because if we’re not going to address it, it looks pretty catastrophic to us. And so I think, when we start talking about climate change, absolutely pushing to make sure that we’re thinking about a mindset of how we fit into nature, rather than nature fitting into us.

HCN: These kinds of discussions, compromises and negotiations can often, especially around water in the West, go on for decades. I’m curious what gives you momentum to keep working at it and putting so much energy into it.

DV: A few different things. You know, those hundred-plus interviews that we did, we got to know people on a real personal basis. We got to know who they are and their commitment — many of these people have had decades working in the Colorado River Basin and doing the best that they could, given the structure. And everybody understands and agrees that the current system is not sustainable, and it doesn’t work; it’s not inclusive of the voices that need to be included into this process. And so that gives me great hope. And then you see things like the pulse flow, where they got water all the way to the Sea of Cortez. And to look at the faces of those Mexican kids who had never seen water in the Colorado River in their whole life come out, and just the wonder and the magic in their eyes of seeing what water does.

And then we just recently had our second basin-wide workshop and gathering up in Phoenix. We had a hundred-plus of the major stakeholders: states, feds, water providers, tribes and four tribal chairman present at this particular meeting, which is just huge, a bunch of people all in this room all talking about their joint commitment to the river. It’s moving to me because, I mean, I think that’s what it’s going to take.

HCN: Every tribal nation is different, but how might a tribal nation view water similarly or differently than a city or a state or the federal government in terms of water and management?

DV: That’s the thing that we’re really trying to create awareness of. Because in the Colorado River Basin alone, you have 29 distinct sovereign entities — geographically, culturally, languages, and mindsets and traditions and culture in terms of how they think about the river. A lot of it’s really about the same, but in terms of the reverence and the spiritual connection that most tribes have, they look at it in different ways. For instance, invasive species of fish: You get tribes who are really aggressive about wanting to remove them because they’re not part of the natural environment that was always there. Then you get other tribes who are just like, eh, who cares and it’s not on their radar. And that’s why it’s important that a conversation about the next set of guidelines for the Colorado River has to include all 29 tribes — in terms of at least the opportunity to participate and at least having the information to determine whether they want to or not.

HCN: What are some big things that you would like people to better understand about the discussions around water in the Colorado River Basin?

DV: I would like them to understand, from a tribal perspective, the incredible role that tribal water already plays in the basin. The other thing I would like people to understand is that this current law of the river is not sustainable. At some point in time there’s collapse. And I think if we don’t address it quickly, that collapse could happen sooner than later. And I really would like to have them understand that the way that the law of the river is structured — upper, lower basins, and how they’re managed differently, and how there’s different requirements and how states are engaged — it’s really complex and doesn’t make any sense, and, ultimately, I don’t think it’s going to get us where the broader consensus wants us to go in terms of a healthy, sustainable river, and still provide water to all living creatures and plants in the basin.

HCN: Specifically, what is it that tribal nations are bringing to the conversation that was lacking in the 2007 agreements?

DV: I think absolutely a point of view about the sacredness of the river that most people really do share, whether they’re tribal or not. And then the other thing is the unique role that tribes are going to continue to play in the West — the large land areas and our resource development and how we move forward. It creates this mindset, in my mind, of building a pathway of who we want to be in the future. But a huge thing, too, is tribes bring certainty to the table. You know, it’s like, wow, what if we negotiated together about being able to move water where it needs to move, and work from a standpoint of collaboration and need rather than protect, defend and win, lose.

HCN: That’s a good point. Because that’s how water is so often talked about, as somebody versus somebody.

DV: And I think that’s what the law of the river does. It’s contentious, and it automatically puts you in a position to protect and defend. And if that’s the foundation we’re operating from, what does that get us? It’s just going to get us this recurring, vicious cycle that we’ve been stuck in. The work that we’re doing at the partnership and Water and Tribes Initiative hopefully has broader implications in terms of tribal sovereignty, and looking at tribal sovereignty from the standpoint of an opportunity to create your future.

Anna V. Smith is an assistant editor for High Country News. Email her at annasmith@hcn.org or submit a letter to the editor. Follow @annavtoriasmith.

Many Indian reservations are located in or near contentious river basins where demand for water outstrips supply. Map courtesy of the Bureau of Reclamation.

#Colorado #Water Leaders Move Forward with Demand Management Investigation — @CWCB_DNR

Brad Udall: “…latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with
@GreatLakesPeck

Here’s the release from the Colorado Water Conservation Board:

Colorado Water Conservation Board Hosts Two-Day Forum

On March 4 – 5, Colorado continued to carve the path forward in its Demand Management Feasibility Investigation during a two-day joint meeting between the Interbasin Compact Committee (IBCC) and eight Demand Management Workgroups.

Hosted by the Colorado Water Conservation Board (CWCB), this was the first workshop convening all eight Workgroups – together representing diverse water-related interests across the state. Workgroups reflected on the past year of discussions and presented on challenges and benefits they foresee in a potential temporary, voluntary, compensated program to address Demand Management.

Demand Management is the concept of temporary, voluntary, and compensated reductions in the consumptive use of water in the Colorado River Basin. Any water saved would only be used to ensure compact compliance and to protect the state’s water users from involuntary curtailment of uses.

“We appreciate the focus, dedication and collaboration of our Workgroup members who gathered this week from across Colorado to move this important conversation forward,” said CWCB Director Rebecca Mitchell. “This workshop was the next step in sharing ideas for Colorado’s water future, and positioning our state as a national leader for cooperative problem solving.”

IBCC Director Russell George said, “We began this process of meeting as individual Workgroups in order to begin exploring concerns and benefits of a potential Demand Management Program. The next step in the process was bringing these Workgroups together in this larger forum, which has fostered the critical conversation needed to ensure we are using a grassroots approach. This approach will help inform our state’s decision-makers as they consider options for a possible Demand Management program.”

Demand Management Workgroups include:

  • Administration & Accounting
  • Agricultural Impacts
  • Economic & Local Government
  • Education & Outreach
  • Environmental Considerations
  • Funding
  • Law & Policy
  • Monitoring & Verification
  • As a headwaters state, Colorado is thoroughly exploring potential tools for managing water in the western United States, and will continue to inform Coloradans throughout the investigation and during the decision-making process.

    Demand Management Workgroup Members brainstorm potential program. Photo credit: Colorado Water Conservation Board

    As 2020 kicks in, historic #ColoradoRiver #Drought Plan will get its first test — @WaterEdCO

    Lake Powell, created with the 1963 completion of Glen Canyon Dam, is the upper basin’s largest reservoir on the Colorado River. But 2000-2019 has provided the least amount of inflow into the reservoir, making it the lowest 20-year period since the dam was built, as evidenced by the “bathtub ring” and dry land edging the reservoir, which was underwater in the past. As of October 1, 2019, Powell was 55 percent full. Photo credit: Eco Flight via Water Education Colorado

    From Water Education Colorado (Laura Paskus):

    This year, the first-ever Colorado River Drought Contingency Plan is set to launch, and water officials expect 2020 to bring unprecedented changes to the way the river is run, including cutbacks in water use by some states.

    Drought and climate change are expected to play a leading role in determining how to reduce water use and bring the stressed river system into a sustainable, balanced state of being.

    After historically low levels were reached last year in Lakes Powell and Mead, Arizona and Nevada are now poised to implement their first-ever cuts in water diversions, while Colorado and the other upper basin states are working to explore ways to conserve water and bank it in Lake Powell’s new drought pool to avoid future shortages.

    Brad Udall, a senior climate scientist at Colorado State University’s water center, said the river’s operations are set for a major rework.

    2019, he said, was “a really big [water] year, so I think everybody’s happy, but to think somehow the drought is over and climate change isn’t happening—or to hope for the best and ignore the lessons of the last 19 years—I think these high temperatures will remind people, ‘This is not the same old game we used to play in the 20th century.’”

    A look back

    A lot has changed since the Colorado River Compact first divvied up the river’s waters in 1922. Today, more than 40 million people in two countries rely upon the river, which originates on the Western Slope of the Rocky Mountains in northern Colorado, and is fed by major tributaries like the Green, Gunnison and San Juan rivers. Cities from Denver to San Diego, though geographically outside of the natural river basin, divert water from the river for drinking and industry, and farmers irrigate 5.5 million acres of everything from alfalfa to melons.

    The Colorado River Basin is also now more than 2 degrees Fahrenheit warmer than the twentieth century average—with “hotter” droughts depleting river flows. By necessity, as the climate continues to change, bringing continued warming and drying, shortage-sharing agreements on the river must continuously be updated to keep changing, too. The Drought Contingency Plan (DCP) was needed as a stop-gap until a new set of operating guidelines, due by 2026, are written.

    The DCP’s predecessor

    The DCP’s origins lie with the Colorado River Interim Guidelines. Written in 2007, the operating guidelines were designed to address the Colorado River’s deteriorating storage levels. They identify how to operate the river’s two major reservoirs, Lake Powell and Lake Mead, under hotter, drier conditions, and to share the risk of shrinking water supplies between the upper and lower basins.

    But the 2007 interim guidelines, while temporarily keeping the basin out of crisis, did not anticipate the extent of drought that the basin would experience. In 2013, then-Secretary of the Interior Sally Jewell directed states to consider additional measures or face unilateral federal action to avoid a potential crisis. With its own interests to protect, including water deliveries to contractors and tribal water rights, the federal government needed states to put a more robust plan in place.

    That led to the latest temporary plan, the DCP, which negotiators say provides some security in avoiding a potential crash of the Colorado River system.

    Six years in the making, the DCP includes two plans, hammered out separately by the lower and upper basin states. The upper basin plan focuses on flexibility in reservoir operations during drought conditions, investigating how to reduce water demands—including with voluntary water conservation programs—and weather modification to augment precipitation. In the lower basin, the process needed to move more quickly because water use already exceeds allocations. Cities and farms in Arizona, California and Nevada agreed to scale back and take deeper cuts as Lake Mead reaches threshold elevations that trigger those cutbacks. This summer, the first threshold was triggered, so Arizona and Nevada will implement their cutbacks this year.

    Developing plans for each basin was tricky considering that within each state there are also individual tribes, competing interests, and conflicts between urban and rural water users. But, pushed by a deadline from U.S. Bureau of Reclamation Commissioner Brenda Burman, in March 2019, the seven states asked Congress to provide necessary authorizations to execute their final plans. In an era when Congress spends much of its time at an impasse, legislators on both sides of the aisle recognized the need for drought planning. In April, federal legislators passed the Colorado River Drought Contingency Plan Authorization Act and the following month, on May 20, representatives from the seven basin states and Department of the Interior signed completed upper and lower basin drought contingency plans.

    Colorado River Basin. Graphic credit: Water Education Colorado

    Not a new problem

    As Eric Kuhn and John Fleck write in their new book, “Science Be Dammed: How Ignoring Inconvenient Science Drained the Colorado River,” even during compact negotiations in the 1920s, records showed the river’s annual flows were lower than the total 17.5 million acre-feet allocated to the seven states and Mexico. In fact, three different studies during the 1920s estimated natural river flows at Lee Ferry at between 14.3 million acre-feet and 16.1 million acre-feet.

    Planners chose to ignore that information, Fleck says, and with it, they ignored convincing evidence showing the basin regularly experienced long periods of drought. “We have rules written down on paper, allocating water across the basin, that essentially allocate more water than the river actually has—and this manifests itself quite differently in the lower basin than the upper basin,” says Fleck, director of the Water Resources Program at the University of New Mexico. Fleck’s co-author Kuhn is the now-retired general manager of the Colorado River Water Conservation District.

    In the lower basin, California, Nevada and Arizona have long overused their share of the river (approximately 7.5 million acre-feet annually, averaged over 10-year rolling cycles), Fleck says, whereas the upper basin states have yet to use more than around 4 million acre-feet (of the “remaining” 7.5 million acre-feet originally intended, but not necessarily guaranteed, for them). But everyone needs to come to terms with the fact that there is less water in the basin, Fleck says. “And that’s what the DCP is,” he says. “The first steps toward a long-term plan for everyone to use less water.”

    Today, Kuhn and Fleck note, the river’s average flow between 2000 and 2018 has been only 12.4 million acre-feet—16 percent lower than the 1906-2017 average of 14.8 million acre-feet per year.

    To use less water, the two basins need their own strategies. In the lower basin, the DCP sets rules to scale back use of lower basin allocations as Lake Mead drops, or until storage conditions improve. Arizona, Nevada and Mexico will see cuts this year, while California could follow in future years if reservoir storage declines continue. Over the past few years, water users already started scaling back voluntarily, and, says Fleck, “The DCP gives the structure that gives us the confidence [the cutbacks] will continue,” he says.

    The upper basin occupies a precarious position of its own, even though it uses less water than it technically could under the compacts that govern its use—use in the upper basin has remained flat, at around 4 million acre-feet per year, since 1990. Because upper basin states must not interfere with a specific quantity of water flowing downstream, they’ll take on much of the burden of dealing with declining flows in a warmer future, Fleck adds. “That means the upper basin has to be sure it has the tools in place to make sure it can continue to meet its compact obligations, to send water out of Lake Powell,” he says. “And it may have to figure out how to conserve water below 4 million acre-feet.”

    Brad Udall: “…latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with
    @GreatLakesPeck

    Challenges of a warming world

    Any planning on the Colorado River—from the crops farmers plant, to the ways in which cities incentivize conservation among customers, to the DCP’s successor—must address the fact that the basin is facing a hotter, drier future.

    Rainfall records, reconstructed from tree ring chronologies that stretch back more than a thousand years, reveal past patterns of southwestern droughts, marked by dry conditions associated with natural climate variability. Today’s droughts in the basin are different. They are notable not just for a lack of precipitation, but also for warmer temperatures, which spur changes in snowpack, increase transpiration in forests and fields, and boost evaporation from reservoirs.

    The U.S. Global Change Program’s Fourth National Climate Assessment in 2018 painted a troublesome picture of reduced water supplies and future food insecurity in the region. It also identified risks to southwestern tribes from drought and wildfire, and challenges to the region’s infrastructure and energy supplies.

    More localized studies of the Colorado River Basin also show that as climate change continues to heat and dry the region, the river’s flows will keep dropping. A 2017 study by Brad Udall, a senior water and climate research scientist at the Colorado Water Institute at Colorado State University and Jonathan Overpeck, dean of the School for Environment and Sustainability at the University of Michigan, showed that flows between 2000 and 2014 averaged 19 percent below the 1906-1999 average, with one-third of those losses due to higher temperatures, versus changes in precipitation. If warming continues, according to that 2017 study, Colorado River flows could decline by 20 to 35 percent by 2050 and 30 to 55 percent by the end of the century.

    A study published the following year by Udall and others reiterated that “unprecedented basin-wide warming” was responsible for the declines, this time looking at 1916 through 2014, when the river’s flows dropped by 16.5 percent during that period, even though annual precipitation had increased slightly. The study also revealed the entire basin’s sensitivity to shifts in precipitation patterns—that it matters whether precipitation comes as rain or snow, and also where it falls. Snowfall in the upper basin is more beneficial to the system, for example, than rainfall in southern Arizona. And the future doesn’t look promising: The 2018 study forecasts a future decline in snowfall within four sub-basins in Colorado.

    Healthier snowpack this past winter offered everyone a bit of a reprieve, but the Colorado River Basin’s problems aren’t over. At the end of the water year, total system storage was at only 53 percent, according to Reclamation, though that’s up from just under 47 percent in October 2018.

    New Study Projects Severe Water Shortages in the #ColoradoRiver Basin — Inside Climate News #COriver #aridification #snowpack #runoff #ActOnClimate #KeepItInTheGround

    From Inside Climate News (Bob Berwyn):

    The loss of the reflective snowpack drives evaporation and reduces the flow of water, the study found.

    In 2018, snowpack in the Rocky Mountains was much lower than usual. Credit: Joshua Stevens/NASA Earth Observatory

    The 40 million people who rely on Colorado River water need to prepare for a drier future.

    Global warming is shrinking the Rocky Mountain snowpack that feeds the river and flows are declining at a rate of about 9.3 percent for every 1.8 degrees Fahrenheit increase in temperature, according to a new study that “identifies a growing potential for severe water shortages in this major basin.”

    The decline is “mainly driven by snow loss and consequent decrease of reflection of solar radiation,” a pair of scientists with the U.S. Geological Survey wrote in a new paper published Thursday in the journal Science. The study helps resolve a “longstanding disagreement in previous estimates of the river’s sensitivity to rising temperatures.”

    The study links dwindling flow of water with the loss of albedo, a measure of the snowpack’s reflective quality. Like ice in the Arctic, white snow reflects solar radiation back to space. But as the snowpack in the Colorado River declines, the ground and, crucially, the air directly above the ground, warm up. Water from the melting snow or from rain evaporates from the soil, rather than trickling into the streams that feed the Colorado River.

    The scientists found the link by measuring the relationship between the amount of water in the snow, the amount of the sun’s incoming radiation and how much of that was reflected back by the snowpack’s albedo, showing that, as the snowpack dwindled, the river’s flow declined.

    Brad Udall: “…latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with
    @GreatLakesPeck

    Brad Udall, a climate scientist with the Colorado River Research Group, said the study “adds another brick in the wall of evidence that it’s very likely we’re going to see significant declines in Colorado River flows.

    “Scientists have been trying to figure out how sensitive the river is to global warming,” he said, “and these numbers put the sensitivity at the upper end of what’s possible.”

    The research divided the Colorado River Basin into 960 sub-areas and broke down the data, including satellite measurements of albedo, month by month. That enabled the scientists to see that the effect was dominant in the late spring and early summer, when the snowpack was being depleted, said Chris Milly, the senior U.S. Geological Survey researcher who led the new research. Previous studies on the Colorado River’s climate sensitivity focused primarily on precipitation and temperatures, without considering the radiation balance, he added.

    “Before our study there was a huge range of estimates of how sensitive Colorado River flows are to warming, from 2 percent to 15 percent for every 1 degree Celsius of warming. We really wanted to try and understand and narrow that uncertainty,” Milly said.

    It’s not just a Colorado problem. “Many water-stressed regions around the world depend on runoff from seasonally snow-covered mountains,” the authors wrote in the journal report, “and more than one sixth of the global population relies on seasonal snow and glaciers for water supply.”

    The findings suggest that the snow cover offers a “protective shield” that limits evaporation from this natural reservoir, the scientists wrote in the study. As the shield shrinks, it will crimp water availability in snow-fed regions that are already stressed, including the Colorado River Basin…

    Unending Stream Flow Decline

    University of Michigan climate researcher Jonathan Overpeck said the new study is valuable because it details the mechanism “by which regional human-caused warming is reducing flows in the Colorado River.”

    Continued warming, he said, “will lead to significant and unending reductions in river flows. Until global warming is stopped, the Colorado and other key rivers of the Southwest will continue to provide less and less water to the region.”

    […]

    Colorado River Basin. Graphic credit: Water Education Colorado

    Research since then has confirmed that global warming is affecting water supplies in the West in several different ways. As early as 2013, U.S. Geological Survey research showed that warmer spring temperatures since 1980 have cut the Rocky Mountain snowpack by 20 percent.

    A 2016 study in California’s Sierra Nevada Mountains showed how the snowfall line is speeding uphill. At lower elevations where the mountains aren’t so steep, tens of thousands of square miles that used to be white all winter now stay brown and heat up, and the moisture in the soil evaporates.

    In 2017, Overpeck, along with Udall, showed a clear relationship between warming temperatures and less water in the Colorado River Basin, as they studied the Colorado River’s 21st century “hot drought.”

    Extremes

    The new study doesn’t take into account extreme events like the crippling 2012 drought that sent Colorado River flows to record lows while reservoir storage plummeted.

    By the end of May that year, 100 percent of Colorado was in some stage of drought, including the mountains that supply more than three-quarters of the Colorado’s total flow. It would end up being Colorado’s hottest year on record, as well as one of the state’s worst wildfire seasons, burning a quarter million acres and causing temporary evacuations of 35,000 people.

    But so-called Black Swan climate events like megadroughts lasting several decades have happened regularly in the last few thousand years, and are increasingly likely in a world that’s cooking in a thickening stew of greenhouse gases.

    In May 2019, the Colorado River Research Group published a warning about “unexpected shocks from Black Swan events.” That includes megadroughts or extreme floods, as well as “socioeconomic events that might stress the existing legal/management framework beyond any known circumstance,” the report said.

    Because of global warming, the chances of such events are increasing at the same time that reservoir storage and groundwater reserves are being depleted, a disconcerting situation “given the role of multiple megadroughts in undermining past civilizations in the region,” the river researchers wrote.

    They said planning scenarios should be based on water records that stretch back longer than the last century, and should take into account that “the abnormally wet period of the early 20th century … might be better viewed as a highly unlikely hydrologic event that cannot be assumed to be part of the future.”

    The paleoclimate record clearly shows that the first 100 years of the European settlement era in the Colorado River Basin was an unusually stable period of abundant water, and that there were sudden extreme swings between drought and floods during past geologic eras of rapid climate change.

    One of most severe drought periods on record in the Colorado River Basin was between the years 900 to 1300, when regional temperatures close to today’s triggered “a period of extensive and persistent aridity over western North America,” according to a 2010 study in the Proceedings of the National Academy of Sciences…

    Overpeck said, “The good news is that we understand what is happening to the Colorado River and why. This means we can have confidence on the solution, which is putting a rapid stop to climate change, mainly by ending the burning of fossil fuels.”

    He added, “Simply put, the more oil and gas we burn, the less water will be available to the American Southwest.”

    Confluence of the Little Colorado River and the Colorado River. Climate change is affecting western streams by diminishing snowpack and accelerating evaporation, a new study finds. Photo credit: DMY at Hebrew Wikipedia [Public domain]

    From KUNC (Luke Runyon):

    Using hydrologic models, researchers with the U.S. Geological Survey, found that the Colorado River basin is extremely sensitive to slight changes in temperature. In their new paper in the journal Science, they show for each degree Celsius temperatures rise, flows in the river are likely to decline more than 9%.

    That decline is likely to cause severe water shortages in the Colorado River basin, where more water exists on paper in the form of water rights than in the river itself. Warmer temperatures diminish snowpack, lessening the amount of water available…

    The reductions might sound small, Milly said, but they will be felt throughout the basin.

    “There’s not a lot of slack in the system,” Milly said. “In the long-term communities, states will be making adjustments to how they allocate water.”

    […]

    The finding comes as water managers throughout the watershed are gearing up for negotiations over a long-term plan for the river’s management. The Colorado River’s current operating guidelines expire at the end of 2026, and the states that make up the watershed are required to start negotiating new ones by the end of this year.

    “The new rules must consider how to manage the river with unprecedented low flows in the 21st century,” Udall said. “The science is crystal clear — we must reduce greenhouse gas emissions immediately. We now have the technologies, the policies and favorable economics to accomplish greenhouse gas reductions. What we lack is the will.”

    Click here to get access to the paper.

    Roaring Springs Waterfall along North Kaibab Trail. Photo by Whit Richardson via MyGrandCanyonPark.com

    From The Washington Post (Juliet Eilperin, Chris Mooney):

    Up to half of the drop in the Colorado’s average annual flow since 2000 has been driven by warmer temperatures, four recent studies found. Now, two U.S. Geological Survey researchers have concluded that much of this climate-induced decline — amounting to 1.5 billion tons of missing water, equal to the annual water consumption of 10 million Americans — comes from the fact that the region’s snowpack is shrinking and melting earlier. Less snow means less heat is reflected from the sun, creating a feedback loop known as the albedo effect, they say.

    “The Colorado River Basin loses progressively more water to evaporation, as its sunlight-reflecting snow mantle disappears,” write the authors, USGS senior resource scientist Chris Milly and physical scientist Krista A. Dunne…

    Milly and Dunne, who analyzed 960 different areas in the Upper Colorado River Basin to determine how disappearing snowpack influenced the river’s average annual flow, determined that the flow has dipped 9.3 percent for each temperature rise of 1 degree Celsius (1.8 degrees Fahrenheit). The average annual temperature for the area they surveyed has risen 1.4 degrees C (2.5 degrees F) in the past century, Milly said in a phone interview.

    The region is poised to warm even more in the years ahead, Milly said, and it isn’t “likely” that precipitation can compensate for these hotter and drier conditions. Comparing the Colorado River’s historic flow between 1913 and 2017 to future conditions, he added: “That flow, we estimate, due to the warming alone would be reduced anywhere from 14 to 31 percent by 2050.”

    Colorado State University senior scientist Brad Udall, who has written two papers attributing half of the Colorado River’s lower flows to warming temperatures, said in a phone interview that researchers now “have multiple lines of evidence pointing to a very similar number.”
    “And this number is worrying,” Udall said of the new study. “I would say eye-popping.”

    […]

    Andrew Mueller, general manager for the Colorado River District, said in an email that the new findings provide “confirmation of significantly grim indicators about future flow in the Colorado River.”

    The amount of water that would disappear with another 1 degree C temperature rise, he added, is nearly five times what Las Vegas uses each year. “A decline in flows of this magnitude will present a significant challenge to all inhabitants in the Colorado River Basin.”

    The current operating rules for the river expire at the end of 2026, and negotiations over how to share the water going forward start this year.

    Udall said that in light of current projections, policymakers need to consider crafting an agreement where all the major players in the West will use less water than they do now.
    “These projections are dire, but we’re looking at a glass that’s 70 percent full, not half full,” he said. “It could be grimmer.”

    Officials at the U.S. Bureau of Reclamation, who brokered a drought contingency plan among seven states and Mexico last year, said that they are continuing to monitor the way climate change is affecting the river.

    “Reclamation works closely with ​leading scientists at the state and federal level, as well as universities to understand the potential impacts of climate change on the Colorado River,” said bureau spokesman Marlon Duke. “We will continue to use the best available science to manage the river to sustain reliable water far into the future.”

    Center for #ColoradoRiver Studies: Strategies for Managing the Colorado River in an Uncertain Future #COriver #aridification

    Click here to read the White Paper (Jian Wang, David E. Rosenberg, Kevin G. Wheeler, and John C. Schmidt). Here’s the executive summary:

    Colorado River managers and stakeholders face many uncertainties—issues like climate change, future water demand, and evolving ecological priorities. Managers and stakeholders are looking for new ways to communicate about uncertain future conditions, help cope with an uncertain future, and develop public policy when future conditions are highly uncertain. Historically, Colorado River managers have operated Lake Powell and Lake Mead under the assumption that the future natural flow regime of the Colorado River at Lee Ferry will resemble the previously observed regime, but most climate scientists believe that the flow regime is changing, and that future flows will be lower, more variable, and more uncertain.

    • It is also difficult to predict future demand for Colorado River water, future river ecosystem conditions, or the values that future generations will attach to those ecosystem conditions. These uncertainties present immense challenges when developing river management policies to enhance water supplies and ecosystem condition.
    • To help Colorado River stakeholders think about, talk about, and better manage the river in the face of these unknowns, this white paper distinguishes four levels of uncertainty. Future conditions can be described by point estimates with small ranges (Level 1), probabilities (Level 2), scenarios of possible future conditions (Level 3), or a level of complete unknown (Level 4).
    • We represent each level with day-to-day and Colorado River examples. These examples illustrate how the further a stakeholder attempts to peer into the future, the greater the level of uncertainty.
    • Managers and stakeholders can classify the uncertainty level of each key system factor to guide decisions about which modeling tools and public policies to use. Tools include defining alternative scenarios, Many Objective Robust Decision Making (MORDM), Decision Scaling (DS), and Dynamic Adaptive Policy Pathways (DAPP) for uncertain future conditions that can only be described by scenarios (Level 3).
    • There is need to expand the discussion about how to renegotiate the Interim Guidelines and the Lower Basin Drought Contingency Plan (DCP). This discussion should consider uncertainties in future hydrology, demands, and river ecosystem conditions that can only be described by scenarios (Level 3). Revisions to the Interim Guidelines should (1) include more information about future conditions as new information becomes available, (2) define interim decision points (called signposts) when existing policies should be reconsidered, and (3) allow more flexibility in day-to-day management decisions that respond to unforeseen conditions.
    • This white paper suggests that new guidelines designed to adapt to uncertain future hydrology, water demand, and river ecosystem conditions are likely to look quite different than the current guidelines, which seek to provide certainty about the amount of water managers can divert.
    • New guidelines that acknowledge different levels of uncertainty levels will be more adaptable, more flexible, and will be better able to anticipate and respond to a wider range of future Colorado River conditions. This adaptability and flexibility can help avert future crises.

    2020 #COleg: Legislative Water Priorities in 2020 for #Colorado’s Rivers, Birds, and People — @AudubonRockies #ColoradoRiver #COriver #DCP #aridification #COWaterPlan

    Rocky Mountain National Park October 2019. Photo: Evan Barrientos/Audubon Rockies

    From Audubon Rockies (Abby Burke):

    Policy priorities for the 2020 Colorado legislative session.

    Colorado lawmakers returned to the Capitol on January 8th to kick off the 2020 legislative session. Even before bills were introduced, it was clear that the General Assembly will wrangle with issues that will touch every corner of the state and impact the daily lives of Coloradans. Water is one of these key issues.

    Despite the optimism from a snowy December, Colorado’s snowpack is now starting to fall closer to average. Although Colorado is perched at 108 percent average snowpack statewide, much of the West Slope remains in drought conditions. With enough snowpack, flurries will melt and become flows for healthy rivers that support all of us. But as water supplies are becoming more unpredictable, sharing a limited water supply—statewide—between urban, rural, agriculture, industry, environmental and recreational needs is the challenge at hand.

    Audubon Rockies is working with lawmakers and partners to prioritize water security for people, birds, and the healthy rivers that we all depend upon. Colorado’s birds and people cannot thrive unless our rivers do too. Here are three water priority areas for Audubon Rockies in the 2020 Colorado legislative session.

    Funding Colorado’s Water Plan

    Water security for Coloradans, birds, and rivers begins with implementing the state Water Plan. In the light of climate change and booming population growth, Colorado’s Water Plan, finalized in 2015, aims to ensure a sufficient supply of water for the various users across the state including environmental, agricultural, municipal, industrial, and recreational needs. Implementing Colorado’s Water Plan is projected to cost $3 billion in total, or $100 million a year over the next 30 years.

    In November 2019, voters approved Proposition DD to legalize sports betting and a 10% tax on these casino revenues which will result in an estimated $12 million to $29 million annually, the majority of which will go toward the Water Plan. Proposition DD is expected to generate more than $7 million in new tax revenue for the Colorado Water Plan in 2020, a significant bump up from past funding sources.

    At this point, it is not clear how the state will spend these dollars given the various priorities and the considerable Water Plan funding gap. The language in DD was vague and will need refinement and transparency. Stakeholders and lawmakers will likely explore options with the legislature to guide how DD funds are spent on Water Plan implementation.

    Audubon will advocate for spending that supports healthy rivers for the birds and people that depend on them, as we support a fully funded Water Plan.

    Supporting the Colorado River

    In 2019, the Drought Contingency Plan was adopted by the upper and lower Colorado River basin states. One of next steps for Colorado and the other upper basin states is to investigate the feasibility of a demand management program. The Water Resources Review Committee recommended SB20-024 to create a robust public engagement process similar to the development of the Water Plan before adopting any rules or recommendations regarding demand management. While public input is nearly always a positive, this process seems to get ahead of the process established by the Colorado Water Conservation Board’s (CWCB) demand management workgroup. Audubon is monitoring SB20-024.

    With Colorado’s water supply becoming more unpredictable and valuable, particularly on the West Slope, concerns were raised by the Water Resources Review Committee to address anti-speculation. Specifically, concerns were raised that agricultural water rights are being sold to entities with no real interest in farming or ranching in Colorado that are holding those rights for future, more profitable transactions. SB20-048, Study Strengthening Water Anti-Speculation Law, would create a working group to explore ways to strengthen anti-speculation laws and report its findings and recommendations to the committee next year. Audubon is in favor of SB20-48 to keep Colorado’s water out of the hands of risky transactions. We need to support our agricultural heritage and the habitats our working landscapes provide.

    Instream Flow

    For the second year, Colorado lawmakers will see the return of two similar bills attempting to expand the instream flow program. Since 1973, the instream flow program has given the CWCB the unique ability to hold instream flow rights—water rights with the sole purpose of preserving the natural environment by remaining in streams or lakes. First, HB20-1037, Augmentation of Instream Flows, is essentially a rerun from last year with key benefits for the Cache la Poudre River near Fort Collins. The bill permits the CWCB to use water for instream flow purposes, if the water has been decreed for augmentation without seeking a further change of use in water court. (Augmentation water restores water uses that are out of priority.) This would create a new pool of water, with lower administrative costs, which could be available for instream use.

    The second bill, HB20-1157, Loaned Water For Instream Flows To Improve Environment, looks to expand the existing instream flow loan program. Under the current law the instream flow loan program allows water right holders to loan water for three years out of a 10-year period to the CWCB to preserve water for rivers where there is an existing instream flow water right. The current program participation is not renewable.

    HB20-1157 looks to expand the instream flow loan program by increasing the years of participation from three to five years in a ten-year period, and allow for two additional ten-year renewal periods. It also supports greater notification to local water users, provides for an expedited process to address water-short river emergencies, and adds a longer term procedure for loaning water to instream flow decreed river segments for improvement of the environment. The instream flow loan program is completely voluntary and allows greater flexibility for the water right holder to use their property right in a beneficial way.

    In 2019, a similar bill to HB20-1157 passed the House of Representatives only to die in Senate Committee. Perceptions around the potential impacts to soil health from fallowed fields and on historical irrigation return flows from leaving water in stream rather than applying it on the land may have caused the bill to fail. With robust engagement and input from Audubon, partners, stakeholders and the Colorado Water Congress over the past year, bill sponsors are more optimistic for successful instream flow loan expansion in 2020.

    Audubon supports multiple tools in the toolbox to support healthy rivers, agriculture, and economies. HB20-1157 and HB20-1037 bring greater flexibility and beneficial options for rivers and water right holders.

    A new Colorado bill would allow water users to divert less water during dry years, helping to keep rivers flowing. Amid climate change, our rivers need this kind of flexibility. Urge your representative to support HB20-1157.