The Rio Grande is full as much of New Mexico's snowmelt rushes by

May 9—The Rio Grande is broad and rushing, cold mountain water filling its riverbed in Albuquerque. While farmers are getting irrigation water this week, irrigation deliveries in the summer are expected to be limited.

New Mexico's snowpack this year melted a week or two earlier than average. Most of the snow has melted , although roughly 2 to 3 inches of snow-water equivalent remains in the Tusas Mountains and the Sangre de Cristo Mountains, said Andrew Mangham, a senior service hydrologist with the National Weather Service's Albuquerque office.

"There is still a little bit more snow kind of up in the Chama area that will feed into the Rio Chama and the Rio Ojo Caliente. And in the Sangre de Cristos — that'll feed several rivers up there, including the Pecos and some of the tributaries that flow into the Rio Grande on the west slopes," Mangham said.

That snow will likely melt within the next week, so as the water runs from the mountains into streams and rivers, they will flow high and fast with very cold water for the next month.

At the beginning of April, high temperatures melted snow and brought the river flows up rapidly, said Anne Marken, water operations manager for the Middle Rio Grande Conservancy District, or MRGCD. But as temperatures cooled down near the end of April, snowmelt slowed and river flows stabilized, she said.

A 'remarkably late' snowpack

New Mexico had a decent snowpack in the mountains with a level comparable to last year, Mangham said.

"Not quite as strong, not quite as high, but it was still a pretty healthy snowpack," Mangham said.

However, snowpack in Colorado at the headwaters for the Rio Grande and the San Juan River was significantly lower than last year, driving lower water supply forecasts, Mangham said.

Despite an above-average snowpack in New Mexico, the Middle Rio Grande Conservancy District is anticipating below-average stream flows, in part because of poor soil moisture, Marken said. Drier soil absorbs more water, sending less on to the river.

The snow was remarkably late in New Mexico this year, Mangham said.

"We had a pretty dry winter, and then it set up quite late in March, and we got quite a bit of snow and that sort of saved our bacon when it comes to water supply. Otherwise, it's been a very, very dire year indeed," Mangham said.

Typically, El Niño winters such as the most recent one give snowier, colder winters, but New Mexico's dry winter in an El Niño year demonstrates that El Niño and La Niña effects aren't a guarantee, Mangham said. The climate patterns just affect the odds. El Niño and La Niña are opposing climate patterns centered in the tropical Pacific Ocean that affect weather all over the globe.

Mangham urged caution as spring runoff continues to come down streams and rivers.

"This water is extremely dangerous. It looks fine, but water that is 40 to 50 degrees, if someone falls into that, you'll be incapacitated almost immediately as your body goes into shock, and it's very easy in that situation to get in real trouble and drown," Mangham said.

Lots of water now; what about later?

On Tuesday, 3,000 cubic feet per second of water was being released into the Middle Rio Grande below Cochiti Dam, which is 50 miles north of Albuquerque. Some of that water is being diverted to farmers, while the excess is going to the Elephant Butte reservoir in southern New Mexico.

"That's way more water than we need to meet the demands of the crops in the Middle Rio Grande," Marken said.

The MRGCD offers irrigation and river flood control, along with water conservation services for farmers in the Middle Rio Grande Valley.

The MRGCD started charging irrigation canals — using water to clean out the canals — several days early on Feb. 26. Irrigation season is typically March 1 to the end of October. Water deliveries to farmers began in the middle of March and are ongoing, Marken said.

The water headed to Elephant Butte will count toward New Mexico's Rio Grande Compact delivery requirements. The Rio Grande Compact is a legal agreement signed in 1938 between Colorado, New Mexico and Texas allocating how much Rio Grande water each is entitled to.

Although there is excess water for New Mexico's farmers this week, they can expect limited irrigation deliveries in the summer and fall if there are not inflows from monsoon storms, Marken said.

That's because MRGCD cannot store any water on the Rio Chama's El Vado Dam, which is undergoing repairs, and because of the Rio Grande Compact requirements.

"If we had El Vado available to us and there weren't Rio Grande Compact restrictions, we would be storing some of this water in El Vado. So when spring flows come down in the summer and the amount isn't enough to meet what the crops need, we'd start releasing from storage to fill that gap. But we don't really have that tool available to us, and we haven't for a couple of years," Marken said.

The MRGCD does have some water it can store from the San Juan Basin in northwest New Mexico and southern Colorado that is not subject to the rules of the Rio Grande Compact, but it will not be enough water to meet farmers' crop needs, she said.

To fill that gap, farmers will need summer rains.