The ‘academic proposal’ for the #ColoradoRiver — The #Aspen Daily News #COriver #aridification

The Roaring Fork River just above Carbondale, and Mt. Sopris, on May 3, 2020. Photo credit: Brent Gardner-Smith/Aspen Journalism

Click the link to read the article on the Aspen Daily News website (Austin Corona). Here’s an excerpt:

May 21, 2024

Two groups of states submitted conflicting proposals in March describing how federal officials should manage reservoirs on the Colorado River after 2026. Former Colorado River Water Conservation District General Manager Eric Kuhn, along with two other water experts, have their own idea to pitch. Kuhn and his co-authors, University of New Mexico professor John Fleck and Utah State University professor Jack Schmidt want to add more flexibility to dam operations to address environmental and recreation concerns in the Grand Canyon below Glen Canyon Dam (the dam that forms Lake Powell). Kuhn presented what has been called the “academic proposal” during a Colorado Basin Roundtable meeting in Glenwood Springs on Monday. He said the document is not a “proposal” akin to the states’ proposals, describing it as more of an “approach” that can be incorporated with other proposals. 

“What we’ve proposed is a one-speed bicycle with pedal-back brakes,” Kuhn said. “What all of the parties are likely to negotiate for an actual accounting system is more like a Mars rover.”

The two alternatives submitted by the states propose regulations that will layer on top of the 1922 Colorado River Compact to regulate how federal officials release water from major reservoirs after current regulations expire at the end of 2026. One proposal, submitted by the “Upper Basin” states (Colorado, Utah, New Mexico and Wyoming) would regulate releases from Lake Powell, while the “Lower Basin” states (California, Arizona and Nevada) proposal reaches farther to affect releases from Powell, Lake Mead and five other reservoirs spread across both basins…

Kuhn’s, Fleck’s and Schmidt’s solution, Kuhn said, is to allow the U.S. Secretary of the Interior to adjust Glen Canyon releases when necessary to address these diverse and changing issues. Every time managers adjust for environmental or other concerns, though, it will mean that Powell (which is in the Upper Basin) or Mead (in the Lower Basin) ends up with a different amount of water from what the guidelines officially dictate. To deal with this disparity, the authors propose setting up a special “account” of water in one reservoir that compensates for unexpected losses in the other. If managers choose to release more water from Powell than expected, it means the Upper Basin lets more water flow to the Lower Basin than is obligated. Therefore, that water would be held in an “account” in Lake Mead, and it would count against Powell’s future releases to the Lower Basin. The reverse would be true if managers release less water from Powell than expected — they would set up an account in Powell that would later add on top of future releases to Mead. 

“New plot using the nClimGrid data, which is a better source than PRISM for long-term trends. Of course, the combined reservoir contents increase from last year, but the increase is less than 2011 and looks puny compared to the ‘hole’ in the reservoirs. The blue Loess lines subtly change. Last year those lines ended pointing downwards. This year they end flat-ish. 2023 temps were still above the 20th century average, although close. Another interesting aspect is that the 20C Mean and 21C Mean lines on the individual plots really don’t change much. Finally, the 2023 Natural Flows are almost exactly equal to 2019. (17.678 maf vs 17.672 maf). For all the hoopla about how this was record-setting year, the fact is that this year was significantly less than 2011 (20.159 maf) and no different than 2019” — Brad Udall

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