As Rio Grande water dwindles to a mere trickle in the Albuquerque area for the first time since the early 1980s, irrigators are facing the possibility that only the Pueblos will be able to draw water from the river.
A 1928 agreement means that Pueblo water rights are considered “prior and paramount.” That means the six Middle Rio Grande Pueblos will be able to take water from the river when other users are cut off.
The Middle Rio Grande Conservancy District has now used all of the available San Juan-Chama water it had in storage. That means it is relying on the base flow of the river and on water from monsoon events.
Because of the Rio Grande Compact, MRGCD is only able to store San Juan-Chama water, meaning water pumped from the San Juan River, which is part of the Colorado River Basin, to the Rio Chama, which flows into the Rio Grande.
A stream gauge that measures the Rio Grande’s flow near Alameda shows it flowing at 18 cubic feet per second as of Tuesday. A week ago, it was flowing at 138 cubic feet per second and, when the month began, the flows were more than 400 cubic feet per second, at times reaching up to more than 1,100 cubic feet per second amid monsoon storms.
Tuesday’s flows were slightly higher than Monday’s when the gauge read 6 cubic feet per second.
Anne Marken, the MRGCD water operations division manager, told NM Political Report that the inability to store water due to the rehabilitation of El Vado Reservoir and compliance with the Rio Grande Compact contributed to when the channel began to dry. Normally, she said, the MRGCD would release water from storage to prevent river channel drying.
In a press release, Jason Casuga, the MRGCD CEO, said the rehabilitation of the reservoir “is critical for the safety of the facility but unfortunately means the Dam is unavailable for storage until at least 2024.”
The drying of the Albuquerque stretch was not unanticipated. Marken said the conservancy district’s board was even preparing for it to occur earlier in the year—in June rather than July.
Board minutes from a May 31 special meeting show that Marken warned that the Albuquerque reach could experience drying this summer.
“We were anticipating these conditions, the monsoon kind of changed a little bit,” Marken said.
Monsoon storms helped delay the drying of the channel and, Marken said, even if El Vado was not undergoing rehabilitation, the river channel would likely have gone dry.
She said instead of the drying coming at the end of June, as previously predicted, the monsoon kept the channel wet through most of July. Now it looks like the river will go dry in late July or early August in the Albuquerque stretch.
Downstream, it is not uncommon for the San Acacia reach to dry up during the summer and Markin said the drying of the Albuquerque reach could become more frequent under climate change models.
The last time the reach went dry, in the 1980s, a period of wet years ended that trend, according to State Engineer Mike Hamman who spoke to the Legislative Water and Natural Resources Committee this week.
Since the 1980s, water management has changed in part because of the need to protect endangered species. This has contributed to the four decades when the river did not run dry in Albuquerque.
Water management practices need to change once again to deal with a future with less water, according to David Gutzler, a climatologist at the University of New Mexico who spoke to lawmakers during the committee hearing on Monday.
“History suggests that severe droughts have occurred naturally in this part of the world for many centuries,” Gutzler said. “And I anticipate that the current horrible drought will end one of these years and supplies will return at some level.”
However, with climate change, he said it may not return to what the state has previously recorded.
The flows into Elephant Butte under climate change models start to resemble what the state water managers currently view as drought-diminished, he said.
Current water management practices will not work in an era of diminished supplies, like the climate change models show will happen. Gutzler said state policymakers have a choice. They can rewrite management practices to take into account the lessened supplies or they can continue with the current water management practices. Should they choose to do the latter, Gutzler warned that the state will enter into an era of perennial crisis management.
Existing water rights, he said, represent an over allocation of available water.
Gutzler said to increase water the state would have to either import it—which could be hard because New Mexico would be competing with its neighbors for that water—or find new sources such as desalinization or produced water.
Meanwhile, the MRGCD is focused on delivering water to Elephant Butte when possible in hopes of reducing the water debt New Mexico owes Texas in hopes that someday the state will be able to store water from the Rio Grande once again, Marken said.