#Snowpack/#Drought/#Runoff news

Westwide SNOTEL basin-filled map April 4, 2018 via the NRCS.

From The Sky-Hi News (Lance Maggart):

Across Colorado, snowpack figures range from a low of 51 percent in the San Juan River Basin to a high of 93 percent in the North Platte. Statewide Colorado’s snowpack stands at 70 percent of average with the northern portions of the state seeing higher snowpack figures.

“We were at 103 percent last year and only 58 percent back in the drought year of 2012,” stated Natural Resources Conservation Service officials in a recent press release announcing the April snowpack figures.

The Kremmling field office of the NRCS, a division within the federal Department of Agriculture, tabulates snowpack figures in Grand County. While all snowpack calculations provide valuable data the April 1 count is considered the most critical data set for predicting spring runoff figures and summer water supplies, according to Volt.

“Lack of snowfall and warm weather during March, which is usually our snowiest month, has melted all of the valley snow and most of the mid-elevation snow up to 8,500 feet,” stated NRCS officials. “Snow density is averaging 30 percent, which means that for every foot of snow there are 3.6 inches of water and that’s about normal for April 1.”

Officials said additional spring runoff will depend heavily on melting conditions such as temperature and wind as well as an additional spring snowfall or rainfall.

“It would take several good snowstorms to put us back up to average at this point in time,” officials stated. “Irrigators, water users and river runners should anticipate lower stream and river flows for the upcoming summer.”

Around Grand County the specific snowpack figures vary.

The Berthoud Summit SNOTEL site currently stands at 78 percent of average while Willow Creek Pass, north of Granby, stood at 88 percent. The Williams Fork River basin was among the lowest snowpack figures found in the Upper Colorado River Basin on April 1 with the SNOTEL site near the USFS’s South Fork Campground showing snowpack at just 55 percent of average.

The NRCS uses a 30-year average to calculate percentage totals. Currently averages are based on snowpack figures from 1980 through 2010. In 2020 the NRCS will shift their data set and will begin using the years 1990 through 2020 as their data set for determining 30-year averages.

From The Elbert County News (Scott Taylor):

[Emily] Hunt said she considers three things when making forecasts for summer water — snowpack, water supply in the city’s reservoirs and customer use trends.

“All of that stuff for us right now, is looking pretty good — with the exception of snowpack,” Hunt said. “Thornton’s reservoirs are in good shape, slightly above average, and our customers are using water they way we expect them to.”

The March reports for Colorado’s Front Range put snow pack depth at between 77 and 100 percent of annual averages in Colorado’s northern river basins, according to the National Resources Conservation Service. That includes the South Platte, Big Thompson, Boulder Creek and Clear Creek basins.

It’s one of several measurements local water officials monitor all year long as they prepare for the summer. The most important data comes from the April 1 stream flow projection, which has not yet been released by the state.

“It basically takes all the snow pack information, soil moisture reports and reservoir storage across the state and gives us a very specific basin by basin outlook,” Hunt said.

In Westminster, the city is not expecting as heavy runoff but they’ve compensated by keeping the Standley Lake Reservoir full. That should fulfill the city’s needs this summer, as long as the weather doesn’t get especially hot and dry early or residents don’t change their habits, according to Sarah Borgers, Westminster’s Water Resources and Quality Manager.

“It means we are little less reliant on what that snow is doing up in the mountains,” Borgers said. “We are not so dependent on the spring runoff.”

Westminster, Thornton, Northglenn and the Farmer’s Reservoir and Irrigation Company all rely on Standley Lake as one of their main water supplies, but each city has a number of other reservoirs and canals that feed municipal water treatment plants.

Currently, municipal reservoirs are more full than they were last year at this time. Borgers said Standley Lake is close to 100 percent of its capacity.

“We are not expecting to implement drought restriction, but we are keeping a super close eye on the how the rest of the season develops,” Borgers said.

Hunt said Thornton’s reservoirs — which includes smaller reservoirs and retention ponds along the South Platte River — are at about 72 percent. That’s ample room for the spring Thornton expects , Hunt said.

“In addition to Standley Lake, we have about 12 reservoirs along the South Platte as it goes through Thornton,” Hunt said. “They are all in pretty good shape and we should be able to store some water when it comes along in runoff. We are higher than we were last year, but from a supply standpoint we are in pretty good shape.”

Local water officials do have their eyes on the summer of 2019, however. Southern basins are dipping as low as 29 percent of average according to the NRCS statistics, leading to worries of drought in the rest of the state.

“If it stays extremely dry through the summer, we’ll start thinking about our next year,” Borgers said. “We’ll be watching what happens next winter very carefully.”

Layers of dust stripe the sides of a pit dug into the snow in Colorado. Dust deposited or exposed on the surface of the snowpack contributes to faster warming and melting. Center for Snow and Avalanche Studies

From CPR.org (Grace Hood):

Jeff Derry, executive director of the Center for Snow and Avalanche Studies, tracks the amount of dust deposited on snow across the state. He and his assistants snowshoe and ski to 11 high country sites where they measure how much dust there is on the snow surface.

Dust pulls more solar energy into the snowpack, which is essentially a reservoir of water for managers across the West. In dusty years, snow melts earlier. The rate of runoff can increase substantially compared to low dust-on-snow years.

It’s important data for scientists across the West.

“In an extreme dust year, we can see the snowpack disappear on the order of 2 months early,” said research scientist Jeff Deems at the University of Colorado at Boulder’s National Snow and Ice Data Center.

Deems said dust on snow will become an important issue as the West moves toward a future with tighter water supplies.

“Demand is going up and it looks like supply is going down for a number of reasons,” said Deems. “We need to keep the snow on the mountain for as long as possible to allow that water to be available for use in the dry summer months. If it melts off [too early] then all we have are our surface reservoirs which don’t store that much [compared to the volume of water in the snowpack].”

From KUNM.org:

A dozen New Mexico counties have been designated by federal agriculture officials as primary natural disaster areas due to drought.

The U.S. Department of Agriculture made the announcement Tuesday.

The designation allows farmers and ranchers in many areas of the state — from Rio Arriba and Taos counties south to Lea County — to get assistance for losses and damages caused by the dry conditions.

Officials say those in another 15 contiguous counties also qualify for natural disaster assistance.

In all, 27 of New Mexico’s 33 counties are affected by the designations.

The seasonal outlook shows drought conditions are expected to persist in New Mexico and much of the Southwest through June.

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