Water managers are preparing for a below-average summer on the Rio Grande, thanks to limited March snowpack in southern Colorado and northern New Mexico.
This week, the U.S. Bureau of Reclamation and U.S. Army Corps of Engineers released their annual operating plan for reservoir storage and releases on the river.
Ed Kandl, a hydrologist at Reclamation’s Albuquerque office, presented the plan Thursday in a webinar.
Low streamflow is predicted for spring and summer, meaning reservoirs on the Middle Rio Grande will likely be operating under Article VI restrictions by late June or early July. Those restrictions come into play when water levels at Elephant Butte and Caballo reservoirs drop below 400,000 acre-feet and no water can be stored in El Vado or other upstream reservoirs.
“MRGCD will store as much as they can in El Vado before then,” Kandl said. “We hope to have an irrigation season that will last through September.”
At the Middle Rio Grande Conservancy District meeting hosted by phone on Monday, Jennifer Faler, Reclamation’s Albuquerque area manager, said districts should expect a full allocation of San Juan-Chama Project water. That water helps cities and irrigation districts reduce dependence on groundwater. Last year’s plentiful runoff enabled Reclamation to store project water for this year’s use.
The agency doesn’t predict enough water this year to conduct big releases from El Vado and create high flows for the Rio Grande silvery minnow. The MRGCD might do a “jiggle” process – dropping water levels at a diversion dam and then bringing levels up a day or two later – to imitate runoff on the river and create spawning habitat.
David Gensler, the district’s water operations division manager, said there was a lot less water in the river than he likes to see in early April.
“Irrigation demand often rises in April faster than the river does … and the 2020 season is proving this out for us,” Gensler said. “Colorado diversions are pretty much fully online, and that has dramatically affected the flow into the Rio Grande. Flows crossing the state line into New Mexico dropped to as little as 70 (cubic feet per second) in the past few days and that had a strong impact on our flows at Otowi gauge.”
Much of northern New Mexico is experiencing moderate or severe drought, according to data from the National Drought Mitigation Center, but drought is not as widespread as it was this time last year.
Theresa Davis is a Report for America corps member covering water and the environment for the Albuquerque Journal.