Middle Rio Grande Compact Compliance Crisis Deepens

The Middle Rio Grande Uses Much More Than Its Share

Water flowing down the Rio Grande that is legally owned by and destined for Lower Rio Grande water users is being intercepted and consumed in the Middle Rio Grande.

In 2025 through May, the Middle Rio Grande was entitled to 43% of the 239,900 acre-feet this year’s native Rio Grande water supply, as measured at the Otowi Bridge gage—adjusted for upstream storage changes and San Juan-Chama imported water.  The Middle Rio Grande consumed much more, including 38,400 acre-feet of the Lower Rio Grande’s water.  The Lower Rio Grande is entitled to 57%.  It got 39%.

The Middle Rio Grande’s spiraling water debt is out-of-control. New Mexico is on track to violate the compact soon. Texas undoubtedly will sue.

Nat Chakeres, General Counsel for the Office of the State Engineer, described this problem in his excellent presentation at the Water Advocates May 15th workshop. He described preparations underway for the State Engineer’s forthcoming Middle Rio Grande regulatory actions to be announced soon. Nat answered a question saying he didn’t think 2025 deliveries would fall short by more than 76,000 acre-feet—the remaining margin before an outright violation of the Rio Grande Compact. When asked for supporting data, he deferred to the Interstate Stream Commission. My calculations show the Middle Rio Grande has burned through half of that remaining margin as of the end of May.

Nat’s presentation was one of the best: extremely well organized, clearly presented, frankly informative, and very timely. He clearly explained the water the Rio Grande Compact provides to the Middle Rio Grande and what it requires. He traced the shift from the Middle Valley’s small delivery credit in 2018 to a growing water debt that reached 124,000 acre-feet by the end of 2024. He emphasized the urgent need to significantly reduce total depletions from the river. “If the next seven years look like the last seven,” Nat warned, “it will be too late.”

Unless we act now—with enforceable limits—New Mexico could face Compact violation and a loss of control over our water future.

We agree—and we believe it may already be too late. Regardless, it’s much better for the State Engineer as New Mexico’s water regulator to begin strong, appropriate actions in 2025 than to by default cede authority and control to the judiciary.

So, how are we doing this year? As a former ISC Director, I know where to find the data and do the compact math. Think of the following as my best estimate, that of an observer rather than an insider with access to the best data and current information. I’m putting forward my estimates with those caveats, transparently.

In recent years, the total of all Middle Rio Grande water uses has consumed much more water from the Rio Grande than is ours. 2025 continues the spiral. There is no effective state regulation or self-regulation by institutional water users to protect the water commons. Groundwater pumpers are not suffering a shortage and have increased pumping to offset lack of surface water and increased demand. That pumping causes increased river seepage losses and consumes stored groundwater.

The facts of 2025 per my calculations summarized below are alarming.

1. Otowi Bridge Gage Volume to Date: 227,500 acre-feet of water have flowed past the USGS Otowi Bridge gage through May 31, per my calculation based on 15-minute gage readings over the first 151 days of 2025. Some measurements are missing but use of averages is adequate for this preliminary estimate.
2. The 227,500 acre-foot total winter and spring runoff volume is very low. No snowpack remains, in the Colorado or New Mexico Rio Grande headwaters.
3. Otowi Index Flow: The total volume flowing past the Otowi Bridge gage is adjusted to determine the amount of native Rio Grande water subject to the compact’s sharing requirements. To calculate the index, subtract 20,000 acre-feet of San Juan-Chama Project water and add 32,400 acre-feet of native water federal agencies stored for the pueblos. The total volume to date this year that must be divided between the Middle and Lower Rio Grande is 239,900 acre-feet.
4. Delivery Requirement: Of that adjusted total, 57%, or 136,700 acre-feet, is legally allocated to users downstream from Elephant Butte Dam.
5. Actual Delivery: Based on Elephant Butte Reservoir storage and release data, 99,300 acre-feet have arrived—net of all uses and losses between Otowi and the dam, meaning after accounting for diversions, evaporation, and seepage and unknown losses and errors. This is a 39% delivery, must less than the 57% required.
6. Cumulative Deficit: The Middle Rio Grande is entitled to 43%, or 103,200 acre-feet. Middle Rio Grande overuse this year to date is 37,400 acre-feet, increasing the cumulative water debt to -161,400 acre-feet.

From a slight credit in 2018 to a deficit of -161,400 acre-feet in May 2025—our water debt has quickly grown out of control.

Figure 1. The Middle Rio Grande’s Plunge Into Compact Water Delivery Debt

Unless we have a strong monsoon, 2025 will push the Middle Valley even deeper into water delivery debt. If the monsoon is weak, none of the water stored upstream for the pueblos’ indigenous rights is likely to be delivered. Little to none of the steady summer low flows expected at Otowi will make it through the Middle Rio Grande. For much of the summer, the riverbed below Albuquerque will be dry—and when flow resumes, rewetting the channel will consume large volumes of water that will not count toward deliveries.

No emergency declared. No plan. No accountability. Most Middle Rio Grande residents remain unaware of the stakes.

Here we are once again doing little, saying less. The House Appropriations and Finance Committee stripped without comment the Governor’s request to increase the State Engineer’s annual budget $500,000 for staff, office space, and expenses for the agency to address the Compact delivery crisis.  No public emergency is declared. No action plan has emerged.  Reporting is sparse with unheeded exceptions. Most Middle Rio Grande residents remain unaware of the stakes.

The Water Advocates commends General Counsel Nat Chakeres and State Engineer Liz Anderson for their transparency in the General Counsel’s announcement in a public forum that significant policy changes are coming soon, including notices to all large water users, a metering order for all large wells, and the initiation of the Middle Rio Grande adjudication. We appreciate his frank evaluation of our basic alternatives, contrasting the benefits of negotiated agreements with fighting it out first in court only to be forced to settle or having an adverse judicial order imposed. As he put it, there are water uses that are not going away.

We need more, much more, than Nat’s introduction to forthcoming policy changes. If we do not act now—with transparency, accountability, and enforceable limits—New Mexico could face Compact violation, new United States Supreme Court litigation with Texas, and a potentially devastating loss of control over our own water future. Compliance is the barrier against all of that.

Regardless, I urge New Mexico’s two state water resources agencies to become more transparent; They must name, describe, and quantify our vexing water overuse problems. That is the first step toward solving them.

Norm Gaume, P.E. (ret.)

President, New Mexico Water Advocates

A Glossary of Terms for Middle Rio Grande Water Management is available here.

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As a retired professional engineer, I have used care in completing these calculations, but they rely on incomplete information and have been checked only by me. I stand by my conclusions even though I want to make it clear the specific numbers are preliminary and my calculations are simplified. Therefore, I do not warrant the numbers I calculated from provisional and unpublished agency data. If my numbers are incorrect, I hope the ISC will let me know and provide their professional estimates, as referenced by Nat.

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