At the beginning of February, water managers across Southwest Colorado were holding their breath to see what the final six weeks of winter would bring.
Snowfall in February and March can often make or break the summer irrigation season.
By early April, when snow accumulation generally peaks, the tail end of winter appeared more likely to break water managers than make them.
“It certainly didn’t make up for the dry January and February,” said Ken Curtis, general manager of the Dolores Water Conservancy District, which manages McPhee Reservoir. “We’re looking at a pretty significant cut.”
He expects users will receive no more than 50% of their allocated water and could get as little as 25%.
Ken Beck, superintendent of the Pine River Irrigation District, which manages Vallecito Reservoir, said he’s optimistic the reservoir will fill to its 123,500-acre-foot capacity. He needs another 31,000 acre-feet of water to get there. Beck thinks he’ll get it – but probably not much more.
Snowpack water supply in the northern part of the state is at or above 30-year median levels, but those numbers decline the farther south one goes.
The Upper San Juan Basin, which contains Vallecito and Navajo Lake, has 67% of the median snow-water equivalent for this time of year. The Animas basin sits at 76%; the basin containing the Mancos and La Plata rivers is at 65%; and the Dolores basin, which feeds McPhee Reservoir, is at 72%.
Water accumulation in the San Miguel-Dolores-Animas-San Juan subbasin, which spans much of the southwest corner of the state, typically peaks around April 2. This year, however, it appeared to peak more than a week early, on March 23. Snow-water equivalent dipped at the end of March but perked up with early April storms.
Water supply depends on numerous factors, and farmers rely on forecasts that estimate the likelihood of receiving the median amount of water. Those projections consider snowpack, soil moisture and the expected timing of spring runoff.
This year’s below-normal snowpack above McPhee and Vallecito, especially at lower elevations and across a drought-stricken landscape, could mean the snowpack – a natural reservoir that stores water before it reaches dams – may disappear quickly.
“It won’t be long before … we go on call,” Beck said.
A “call” occurs when senior water rights holders invoke their priority in times of low supply, limiting how much water junior rights holders can use. Beck anticipates this will happen by the end of May, meaning some of Vallecito’s 1,400 irrigators could run out of water by early July.
Soil moisture, humidity and temperature can significantly affect water supply, experts say, as warm temperatures accelerate runoff and dry soils sponge up snowmelt before it reaches reservoirs.
Even small weather events going forward matter, said Heather Houk, horticulture and agricultural production specialist for CSU Extension in La Plata County.
“We didn’t get a ton of moisture in town during last week’s event, but the humidity level was at 60-plus percent for much of that time,” she said. “So for over a week, our humidity was around 60-plus percent. And that makes a difference, because you get less evaporation.”
Still, farmers are bracing for a dry summer.
Ute Mountain Ute Farm and Ranch, the 7,700-acre farming operation owned by the eponymously named tribe in Towaoc, will significantly reduce production this summer.
Half of the farm’s fields will be fallow, said General Manager Simon Martinez, and production of corn for the Bow & Arrow Brand’s flagship products will be cut by two-thirds.
“It’s going to be another challenging year,” he said. “... We’re looking at, hopefully, no layoffs, but it will definitely affect people’s hours that are farming and ranching.”
At this point in the season, no one is holding their breath for significant snow accumulation, although precipitation in the coming months could certainly help farmers.
“It could be a tough, dry summer across the southern tier of Colorado and into our neighboring Southwest states,” Curtis said.
rschafir@durangoherald.com
