Click the link to read the article on Ken’s Substack (Ken Neubecker):
September 16, 2026
Walter and I frequently walk along the Colorado River in Glenwood Springs’ Two Rivers Park, where the Roaring Fork joins in. The Colorado has been running reddish brown lately due to some intense rain and blowouts from small tributaries upstream, gullies that normally are dry. Not this summer. The Roaring Fork runs clear, creating a distinct division between the flows, a narrow ribbon of clear cold water that runs alongside the warmer and muddier stream for a long ways before they mix.
Both streams and most others are extremely low, even for late summer. Many of the USGS gauges have exclamation points next to them on the map, meaning “extremely below average”. There are rocks exposed to the air that I’ve never seen before. What little monsoon rain we had didn’t do anything, not even for the dry soils that will likely soak up much of the snow melt next spring before it can reach the rivers.
Years ago when I’d go to water meetings and conferences, back when people referred to our current situation as an unusually long drought, there was some talk about the Colorado River Compact’s requirement that the Upper Basin not cause the river flow to drop below 75 million acre feet (maf) over a ten year running average. Oh, we’ll see that train wreck coming with plenty of time to do something, they all said. That train wreck is now happening. The engine is sliding over the cliff as the States argue about the menu back in the dining car. All that really happened was serious can kicking along the tracks.
The first Upper Basin “tripwire” of 82.5 maf, the 75 maf plus 7.5 maf for Mexico could come as soon as next month. Now the can being kicked is full of lawyers.
So, what does the 1922 Compact actually say? The meat is in Article III:
This is what each basin could expect every year.
This is where the additional 1.5 maf per year, split as 750,000 acre feet due from each basin comes in. There was no agreement on Mexico’s share of the river in 1922, or in 1928 when the Compact was finally ratified. That came in 1944 with a formal treaty regarding Mexico’s share in both the Colorado and Rio Grande Rivers. The Compact negotiators anticipated such an agreement, hence paragraph (c). What they didn’t anticipate were decades of no “surplus”. That’s another story.
The more serious tripwire comes next:
October 1, 2026, may well see the flow at Lee Ferry cross the first line in the sand of a dry riverbed if the ten year running average drops below 82.5 maf for the first time since Lake Powell began filling. Back then water was held in the new reservoir to fill it. Everyone was OK with that. The Colorado River flows upstream were still quite robust on average and Lake Mead had plenty to satisfy the Compact requirements for the Lower Basin and Mexico as Powell filled.
Not anymore. Powell is shrinking rapidly. As of this writing the reservoir is at just under 22% full, and only about 27 feet from the elevation where the dam can no longer run water through the power plants penstocks. And the outflow is still about twice the inflow.
The monsoon rains turning the river reddish brown in Glenwood won’t help.
So what happens if that 82.5 maf tripwire is triggered and one or more states of the Lower Basin place a Compact Call?
It’s complicated.
It would mean a lawsuit between the states, which would go straight to the US Supreme Court. No lower courts would be involved, and it could take years to resolve. The last time there was a lawsuit about Colorado River apportionment it was between Arizona and California. The case was filed in 1952. The Court appointed a Special Master to work it out and recommend a solution. That took ten years. The case was finally argued in the Court in 1963, with a final decision handed down in 1964. That decision finalized the legal structure for allocations in the Lower Basin, based on the 1928 Boulder Canyon Act.
Twelve years for a resolution. We don’t have that much time for any new case on the Colorado River, especially with how the Upper Basin might comply with Article III, paragraph (d), and Mexico’s share thrown in.
In 2018 and 2019 the Colorado River Conservation District (River District) commissioned a risk study to look at how flows might augment storage in Lake Powell as well as what might happen should Lake Powell ever reach a level where Compact deliveries dropped to a point where the 82.5 maf over ten years wasn’t met, causing a Compact Call. It was, in light of today’s situation and the worsening hydrology, a tad optimistic. The first point in the Executive Summary’s Takeaway states:
The critical low level used for the analysis was 3525 feet, the Bureau of Reclamations critical low as well. Today, September 16, 2026, the elevation at Glen Canyon dam is just under 3517. It continues to drop every day, counting down to October 1.
If the Lower Basin states place a Compact Call it very well could be “catastrophic” for water users in the Upper Basin. But there are scenarios where it could be less so. At the very worst all diversions junior to November 24, 1922, or possibly June 25, 1929 when the Boulder Canyon Act was signed, would be curtailed, cut off, until the Compact deficiency is resolved. But that truly is a worst case scenario.
Curtailment would likely be based on what the flow deficit is at Lee Ferry when the call is placed and what increase through Upper Basin curtailment might make up the deficit. Diversions could be cut on a sliding scale, with the most junior taking the biggest hit, going back from today to that date in 1922 or 1929. We wouldn’t probably notice much at first as October 1, the start of the new water year, coincides pretty closely with the end of the irrigation season for most.
The River Districts study looked at various scenarios for Colorado, based on appropriation dates, river basins vs entire West Slope, and amounts of water that might be needed to satisfy the deficiency at Lee Ferry. The biggest hits would be in the Colorado River mainstem, especially with the large trans-mountain diversions taking water to Eastern Slope cities and farms. The Front Range cities, where most of Colorado’s population resides and who rely on as much as 50% or more of their water supply coming from the Colorado River, along with the significant agricultural areas along the South Platte and Arkansas Rivers, could see some pretty significant cuts regardless.
The State, through the Colorado Water Conservation Board (CWCB) and Attorney General’s office did a Compact compliance study some years ago but is keeping that confidential. I can’t blame them. It could become a basis for court arguments and negotiations should a compact call become a reality. The River District study could be as well. It’s worth a read if you are really interested in all this, and anyone who uses water in Colorado, East or West, to fill a tea pot from the faucet, flush a toilet or raise crops should be. They River District study can be found here or on their website.
Monsoonal moisture is still floating water laden clouds over us today, and some have dropped a good bit of rain. But that won’t help much. We are facing a “super El Nino” this winter, which may or may not provide a healthy snowpack. Anything would be better than last winter, except a repeat of that dry season. In any case it will take many years of “normal” snowfall to begin to refill the reservoirs. Given the trend of aridity and climate warming that is not something we should be counting on.
Perhaps, hopefully, the most important part of the compact written at the beginning will be called upon:
Of course the rub here will be in how “equitable division” is defined, and I imagine this could take much of the courts time in a Compact Call. In 1922 that meant an equal share of the rivers water for each basin. Now it could hinge on where the greater “value” is, and what that means. Back in 1922 “beneficial uses” were pretty straight forward. Now there are many more uses of the river deemed “beneficial”.
The needs and values today are quite different from what they were 104 years ago. The Tribes, the environment, recreation, local economies and traditions. All were either excluded in 1922 or covered by broad undefined ambiguity. Climate change wasn’t heard of, even though some scientists at the time had warned about it.
It’s a brave new world we are entering. Business as usual based on a 104 year old piece of paper and the other paper agreements founded on it won’t help us adapt to that world, nor will wishful thinking and other optimistic dreams based on hope. As Brad Udall noted during a recent PBS Newshour Tipping Point presentation, we need to re-think the whole thing. It won’t be easy, but as Udall pointed out it could be good. We need to rethink both what the river can provide and the reality of adapting to that. We also need to rethink the “values” we base our water needs on. It’s not just about endless economic growth anymore. Throwing lawyers at each other only enriches lawyers while it impoverishes us.
Meanwhile Walter and I will continue our ramblings with the river. We’ll also stop by the River District offices to say hi to the many friends there, to add some stress relief and try to keep their heads from graying any faster than they already are.
