The pressure is on: Colorado’s average snowpack statewide masks worrisome water conditions in the south, where water providers are banking on more storms to boost water supplies before snowmelt begins in April.
Much of Colorado’s annual water supply is stored in its winter snowpack, which builds up until early April when it melts and flows into soils, streams and reservoirs. Statewide, Colorado is headed toward that April 8 peak with 92% of its normal snowpack for this time of year. But conditions vary widely from north to south and within individual river basins, leaving some water experts concerned about drought, wildfires and reservoir levels, officials said during a Water Conditions Monitoring Committee meeting Tuesday.
One of those experts is Pat McDermott, who is based in the Upper Rio Grande Basin in south-central Colorado, where the snowpack is 69% of the norm from 1991 to 2020.
“We need to keep having snow. This has been a dismal year for snowpack accumulation,” McDermott, a staff engineer for the Colorado Division of Water resources, said Tuesday. “We had a whole month and a half – from Dec. 1 to Jan. 15 – when it hardly snowed a speck.”
In the northern half of the state, the snowpack is normal, according to the Natural Resources Conservation Service.
The Colorado Headwaters Basin, where the Colorado River begins; the Yampa-White-Little Snake combined basin, which supplies Western Slope communities in the northwestern corner of the state; and the South Platte Basin, which feeds rivers on the Front Range, are all in good condition.
The Laramie and North Platte combined basin was the only region with a higher-than-average snowpack, measuring about 103% the median compared to the 30-year period as of Tuesday. There is a storm in the forecast this week – both small positive notes for an area dealing with persistent drought conditions after a dry summer in 2024.
The snowpack in these regions typically peaks between April 8 and April 26.
With these conditions heading into spring runoff, officials have an eye out for flooding. Flood risk from snow runoff might be suppressed in areas where the snowpack is lower than average, said Kevin Houck, chief of watershed and flood protection at the Colorado Water Conservation Board, which hosts the monthly water conditions meeting.
Some of these northern basins, like the Yampa-White-Little Snake basin, are heading into the summer with little drought and average reservoir levels in addition to the normal snowpack.
In southern parts of the state, it’s the opposite.
Experts are scouring the data. They’re gauging moisture in the soil, pre-runoff reservoir conditions and weather forecasts for the next three months.
Their goal is to assess whether regions are being dealt a bad hand.
A poor snowpack can mean less water flowing into rivers and streams. Some of that subpar runoff can get sucked up by dry soils. That leaves even less water flowing into reservoirs that are already low. Sparse storms in the forecast, and warm or dry conditions can just make matters worse.
These compounding factors elevate concerns about wildfire risk and raise the odds that farmers will have to reduce their crop output because they won’t have enough irrigation water.
That’s what is happening in southern Colorado with more warm and dry weather on the horizon.
“That is not the kind of outlook that we like to see at this point either,” said Russ Schumacher, state climatologist, in a presentation during Tuesday’s water conditions meeting.
Down in the south-central region of the state, McDermott is worried.
At the summit of Wolf Creek Pass, the snowpack is 66% of normal. But down the pass toward Pagosa Springs and the rest of the San Juan River Basin, the snowpack is 45% of average.
“It’s worse this year at Wolf Creek than it was on the same date in 2018, so we’re using 2018 as a potential forecast point here in the Upper Rio Grande Basin this year,” McDermott said. “Of course, 2018 was a terrible year.”
That year, the snowpack peaked March 30 with 6.9 inches of liquid water in the snow. It normally peaks on April 3 with 14.4 inches, according to federal data. Runoff plummeted and ended a month early.
This year, the basin had 7.9 inches of liquid water in the snow as of Tuesday.
In the Upper Rio Grande Basins, there are two positives to consider: The region had good precipitation heading into the winter, which locked more moisture into the frozen soils, and some of the smaller basins have a better snowpack than others.
On the east side of the San Luis Valley, the snowpack in the Sangre de Cristo mountains varies from 30% to 96% of normal in basins that are mere miles from each other. The snowpack near Great Sand Dunes National Park is at 6%.
“It looks like it’s going to be below normal over there on the Sangre de Cristos, but depending on which little basin you’re in, you may have a little better year than others,” McDermott said.
March, normally the region’s snowiest month, has not served up enough snow to make up for the dry winter. It’ll need more snow just to hold onto that before spring runoff starts, he said. The region’s snowpack typically reaches its peak accumulation April 3.
Climate models indicate less than the normal amount of precipitation across southern Colorado for the next week.
McDermott predicted that it will be one of the top 10 worst runoff seasons basinwide since 1900, during the water meeting Tuesday. The basin is heading into a subpar spring runoff with reservoirs that are already low, holding just 20% to 60% of their full capacity.
Sanchez Reservoir stored about 5,000 acre-feet of its 100,000-acre-foot capacity as of Tuesday. One acre-foot of water equals about 325,850 gallons of water and can supply roughly two to four households for one year.
“We’re a little hamstrung,” McDermott said. “We’re running what appears to be a dry year.”
The future outlook does not offer much relief to the basin or other regions of southern Colorado.
The two-week forecast shows higher temperatures across the state, and less-than-average precipitation in the southeastern region, Schumacher said.
Drought conditions are already creeping into the Western Slope, although drought conditions have improved along the Front Range, north-central Colorado and the Eastern Plains. By June, the wildfire risk is expected to be above normal for the southwestern corner of the state, Schumacher said.
“The news is probably tilted toward the bad side in terms of drought,” he said.
