I added the year to the title of this blog post for the search engines. Because what’s going on right now applies to a lot of years since I’ve been writing about this stuff at Inkstain.
I’m gathering string today for the first Water Matters podcast of 2026 (available on Buzzsprout and wherever fine podcasts are downloaded). One string I pulled: total 2025 flow at Otowi, the gateway to New Mexico’s Middle Rio Grande, was just 494,000 acre feet, the lowest since 1981 by my “danger John Fleck doing math” calculation.
Jan. 1 is early to be talking with any confidence about the coming year’s Rio Grande runoff, with another three-plus months of snow accumulation season ahead of us. And I walked to the market this morning to buy carrots in the midst of very light snow flurries! There’s snow on the Sandias! But I’ve got a podcast to help make, and yowza is the first-of-the-year runoff forecast from the NRCS lousy!
Median forecast for Otowi for the spring runoff: 48 percent of the 1991-2020 period of record. Best case (a one in ten chance on the wet side) is that we hit the average. Worst case I don’t even want to think about. San Marcial? Median forecast is just 17 percent of the 1991-2020 period of record. Worst case is so bad that the model breaks, spitting out a negative number.
“Best case is that we hit the average” makes me want to cry.
Worst-case runoff generating a negative number means we are fooling ourselves using the 1991-2020 record to determine “normal” runoff. This worsening multi-year drought is changing at a faster rate than can be represented by comparing to a 1991-2020 baseline. It would be interesting to compare using a 10-year running average as the baseline instead. We must reluctantly accept running out of surface water availability in the quantities we have assumed.
Thanks for getting the blogpost out, John.
From my experience, 500,000 acre-feet in a year at Otowi was manageable…..if the basin had storage capacity to hold runoff and make releases during the summer. So, to me, last year really shows how important storage supplies are after the runoff when summer rains are low. Unfortunately, with El Vado still unable to store and Compact article VII in effect, the basin will be in a similar situation for 2026.
Also, given the La Niña conditions (hopefully eroding), I wouldn’t pay attention to the most probable runoff forecast. It assumes normal precipitation and we aren’t getting that. Water managers probably are evaluating the 70 to 90 percent probabilities as something in that range is “most probable” for the type of winter we are experiencing….
Related to this, I thought OpenSnow’s overview of the winter so far and the parallels to 2017/2018 was quite well put together:
https://opensnow.com/news/post/north-america-mid-winter-2026-season-update-and-long-range-outlook?utm_source=internal&utm_medium=email&utm_term=newsletter&utm_campaign=2025-2026