Wet winter buoys NM rivers, but drought tempers optimism

A wet winter delivered on snowpack in southern Colorado and northern New Mexico, quenching thirsty soils and promising more water in the Rio Grande this year, experts said in a meeting Tuesday.

“We’re in better condition than we have been for a good long time,” said Andrew Mangham, a hydrologist at the National Weather Service Albuquerque office.

A wet winter emerged this year for much of the Western United States, and snowpacks doubled in some portions of the watershed. More than 75% of the Rio Grande’s water comes from snow water – which has diminished in past few decades, a compounding factor of hotter temperatures from human-caused climate change, and less snowmelt making its way downstream from higher demands by soils and ecosystems wracked with drought.

In the presentation, Mangham warned the combination of wetter soils and heavy snowpack could mean more spring flooding – but a good sign for water supplies. In a separate presentation, Bureau of Reclamation officials estimated that April Rio Grande stream flows through Albuquerque are double from last year’s diminished river.

But the effects of longer and deeper drought from climate change, the longtime federal and local management practices to bring water downstream faster for irrigation, and over-allotment of the river’s water for too many people – all have reshaped the Rio Grande.

One good year doesn’t erase that, said Phoebe Suina, a hydrologist and member of the Interstate Stream Commission.

“The snowpack is looking good, but we need to keep our eye on the ball,” Suina said. “We’re still over-allocated where we stand right now; and we need to focus on building the resiliency in our mountains and our landscapes to be the sponges that soak up the water.”

Floods aren’t just because there’s too much water at one time, Suina (Cochiti Pueblo) said, pointing to recent flooding on the Jemez River and faster swings between cold weather and warm days.

“If we’d have a slow temperature change, the water would have more time to soak in and we wouldn’t have as fast a runoff,” Suina said.

Running rivers

Ephemeral streams and waters are flowing again, including the Santa Fe River, a 42-mile long tributary, flowing through downtown Santa Fe into hamlets like La Cienega, before meeting the Rio Grande below Cochiti Pueblo.

With the water running, there is celebration, tempered by the wider context of drought, said Morika Vorenberg Hensley, the executive director of the Santa Fe Watershed Association.

“We’re trying to hold both this celebration of water but also this anxiety and that feeling of paralysis looking towards the future,” Vorenberg Hensley said. “Seeing we don’t have the systems in place to conserve water and prepare for dry years that are inevitable in the future.”

The small river still provides Santa Fe between 30% to 50% of the city’s drinking water when running. And while it’s historically been intermittent, the damming, depletion and straightening of the river drained the once-abundant wetlands along its bank and put it under more strain.

“Our water allocation and management strategies have to, in my perspective, change,” she said. “We have to plan beyond one year of precipitation and water allocation. Because we don’t know what’s coming next year.”

Further downstream, the Rio Grande is occasionally over-banking, and flooding into the cottonwood bosque, and replenishing the ecosystems along the ditch banks.

“There’s just a lot of water out there,” said John Fleck, a professor of practice at the University of New Mexico’s water department.

But while the river is high now, there’s no guarantee it will stay high through the summer. El Vado reservoir is still under renovations, meaning there’s no ability to prop the river up with stored water and release it during warmer months.

“It’s entirely possible that even with the great snowpack, we’ll have pretty low flows through Albuquerque in late summer,” Fleck said.

Fleck warned that a good water year might distract from the reality – that there is less water available for all the current increased demand.

“People need to understand that going forward, there will be less water, full stop,” Fleck said. “It’s a variable system. So some years, there’ll be more, and other years, there’ll be less, but it’s oscillating around a drier middle.”

A boon for agriculture below Elephant Butte

The windfall of water means an earlier start for irrigation seasons in southern New Mexico and far west Texas. For the past couple of years, there was only enough water to run the river for a few months, between June and August.

The news is welcome to Elephant Butte Irrigation District, said Phil King, the engineering consultant for the district, which grows much of the state’s chile, onion and pecans. This year, EBID is scheduled to release a small amount of water for the Rincon Valley in Southern New Mexico on May 1, and initiate the big release “to punch it down to Mexico,” and Texas on May 12.

“We’re looking forward to it,” King said, “We’re going to run out of irrigation season before we run out of water, and we’ll have some carryover going into next year.”

While farmers have already made their crop decisions this season, King said, a good water year like this may have a large impact for planning in the next. And it certainly can help replenish the groundwater, which has been depleted in years of drought. Less surface water means less water can trickle down into different layers of groundwater. In those dry years, farmers pump more to keep their crops alive, since there’s less surface water to use for crops, causing a double-hit to the aquifer.

“This gives us a chance to recover somewhat,” he said.

King said that he doesn’t want to get “carried away” overstating the impact of El Niño atmospheric patterns for the Rio Grande in the coming year. Even though that atmospheric pattern in the Pacific generally means colder, wetter winters for California, occasionally that pattern can “hop over” the Rio Grande watershed.

“I think that’s getting a little ahead of ourselves,” King said. “El Niño does not a good snowpack make.”