Risk of severe water shortages in the seven-state Colorado River Basin have risen dramatically since April with new forecasts indicating that lakes Powell and Mead could hit crisis levels much sooner than previously expected.
U.S. Bureau of Reclamation Commissioner Brenda Burman said the change in the forecast is noteworthy.
“We’re dealing with more uncertainty than we thought,” she said during a virtual press conference Tuesday.
The Bureau of Reclamation is responsible for managing the two storage vessels and monitoring the mountain snowpack and runoff that feeds them every year.
As recently as April, when the last forecast came out, inflows to Lake Powell were projected to be roughly 75 percent of average this year. The latest report, however, indicates inflows will be just 55 percent of average.
In just five months, the risk that reservoir levels could fall low enough by 2025 to threaten power generation and the ability to release physical water to downstream users has risen 12 percent, according to Reclamation.
Carly Jerla, a hydrologist and water modeling expert, runs the modeling team for Reclamation’s Lower Basin operations.
The 21-year stretch of drought in the Colorado River Basin has made the system extremely vulnerable to changes in weather patterns, Jerla said.
“In this system, one year of poor hydrology can influence the ways these reservoirs are impacted for multiple years into the future,” she said.
Reclamation officials stopped short of saying how states should respond to the dire water supply predictions.
Seven U.S. states share water from the Colorado River Basin. These include Colorado, Wyoming, New Mexico and Utah in the Upper Basin, and Arizona, California and Nevada in the Lower Basin. Mexico also relies on the river’s flows.
The two regions in the U.S. are governed separately, with the Upper Basin states overseen by the Upper Colorado River Commission and the Lower Basin overseen by the Bureau of Reclamation.
The river is a major source of water in Colorado, where it supplies roughly half of the drinking water on the Front Range and irrigation water for ranches, fruit orchards and corn fields on the Western Slope and Eastern Plains.
Brad Wind is general manager of Northern Water. It serves cities and farms from Boulder to Greeley and is one of the largest water providers in the state. Wind said the rising risk levels aren’t that surprising.
But, he said, to help the drought-stressed system regain some semblance of balance will require much more work. “We can’t walk away from this.”
Last year, for the first time in history, the seven states agreed to adopt a basin-wide Drought Contingency Plan. The Lower Basin component of that plan is now complete and requires cutbacks in water use as levels in the reservoirs fall and reach certain elevations. Arizona has already had to cut back its water use in 2020 as a result of the agreement, and Mead’s levels have risen as a result of these actions and other conservation programs. Now at 44 percent full, the reservoir is the highest it’s been in six years, according to the Bureau of Reclamation.
But the Upper Basin, though it has agreed to big-picture elements of an Upper Basin plan, has more work to do to define how a major piece of that plan involving large-scale water conservation, called demand management, would work.
Rebecca Mitchell is director of the Colorado Water Conservation Board, the agency managing the demand management study process in Colorado. She also serves on the Upper Colorado River Commission, representing Colorado. In a written statement, she said the 2019 Drought Contingency Plan has provided additional security for the system and that the study will move forward even as conditions on the river worsen.
“Colorado will continue to track the hydrologic conditions, and work collaboratively with the other basin states,” she wrote.
With the new forecast, however, pressure to cut back water use is rising.
Since 2000, lakes Powell and Mead have lost nearly half of their stored water supplies. Back then the system was nearly full, at 94 percent, according to Reclamation. This year the two reservoirs are collectively projected to end what’s known as the water year, on Sept. 30, at just 53 of capacity.
Climate change and warmer temperatures continue to rob the river of its flows. In fact, water flowing into Lake Powell during that 20-year period was above average just four out of the past 19 years, according to Reclamation.
Jerd Smith is editor of Fresh Water News. She can be reached at 720-398-6474, via email at firstname.lastname@example.org or @jerd_smith.
As most of western Colorado is in an extreme drought, most of eastern Colorado is experiencing moderate to severe drought. While earlier in the summer southern Colorado was experiencing the driest conditions, the driest conditions now take up the western half of the state. The dryness extends into the Denver metro area and creeps to the east in the southernmost part of the state.
Treste Huse, a senior hydrologist for the National Weather Service in Boulder, explained that drought in Summit County started slowly this spring, then progressed to an extreme drought quickly. She explained that Summit County saw a dry fall and while winter saw a decent snowpack, the dry spring meant that the soil moisture was fairly dry going into the summer, which increased the wildfire danger. The U.S. Drought Monitor summary noted that topsoil moisture Sept. 13 was rated very short to short in Colorado.
Huse said that Summit County entered abnormally dry conditions by the end of May. The northern tip of the county went into a moderate drought toward the end of July. In mid-August, the area north of Dillon entered a severe drought. By Aug. 18, the whole county was in a severe drought with extreme drought in the north end of the county and the county was fully enveloped in extreme drought Aug. 25.
“It went fast, we just never got any rain,” Huse said. “That happens a lot of times with drought. You start to see a lot of impacts at once because they’re like, ‘I can go another month if we get some rain’ or ‘I can go two more weeks,’ but then finally there’s just no rain.”
In August, the Dillon weather station recorded 0.62 inches of precipitation, according to the National Weather Service almanac. The station records 1.93 inches in a normal year. So far in September there have been 0.41 inches of precipitation recorded at the station, while 1.02 inches is normal. However, September has seen 3 inches of snow so far, 2.5 inches above normal, which Huse said helped conditions.
Despite dry conditions, Huse noted that the reservoirs are still in good shape.
“What saved the reservoir storage was … the good snowpack of 2018-19,” Huse said.
Huse explained that the 2018-19 snowpack helped keep the reservoir full this year as this last winter, the snowpack barely reached average. Currently, Huse said that reservoir storage for the Colorado River Basin is 101% of average and at 86% capacity. As of Sept. 16, the Dillon reservoir is 95% full, according to Denver Water. Huse explained that parts of the Blue River are normal, such as the high reaches.
Last month was the hottest, driest August on record for western Colorado, according to Russ Schumacher, Colorado’s state climatologist and director of the Colorado Climate Center. He was one of three expert panelists who spoke at the third Yampa Basin Rendezvous discussion Thursday, which focused on changes in temperatures and precipitation amid what they described as a rapidly changing climate.
Routt County isn’t the only place topping charts. In its 2020 State of the Climate report, the National Oceanic and Atmospheric Association said the year is gearing up to be the planet’s second-warmest year in 141 years of temperature records. The warmest year thus far was 2016.
According to Schumacher, “These changes are going to affect the water cycle and everything that depends on it, which is pretty much everything.”
Among the most pressing threats climate change poses to Routt County are higher temperatures, reduced snowpack, increased risk of wildfires, more severe droughts and more extreme weather, according to a 2018 Greenhouse Gas Emissions Inventory. These would cause residual impacts to the local economy that depends on the ecosystem for everything from tourism to farming and to public health and safety, the report adds…
Unprecedented drought conditions pose serious risks to the Yampa Valley, from natural ecosystems to the people who depend on the health of those ecosystems. Ranchers have had an especially hard time this summer as they struggle to water their crops. For the second time ever, water managers placed a call on the main stretch of the Yampa River in August, meaning certain water users had to stop or curb their usage.
Longtime Steamboat Springs rancher Adonna Allen said her senior water rights meant she was not as affected by the call as some of her neighbors, but the dry summer has caused problems for everyone in agriculture.
Those growing hay have seen anywhere from 25% to 45% reductions in yields, Allen said. To make up for the loss, Allen had to convert pastures her family normally uses for grazing their cattle into hay fields, pastures she has not touched in 10 years…
Among the most devastating effects of hot, arid conditions for Colorado has been the propensity for large wildfires. The Pine Gulch Fire, sparked by lightning July 31 near Grand Junction, is the state’s largest wildfire in Colorado history. As of Friday, it was more than 139,000 acres in size and 95% contained, following about six weeks of firefighting efforts.
The Middle Fork Fire, 10 miles north of Steamboat, had grown to 5,445 acres Friday, according to the U.S. Forest Service. It continues to spread, fueled by gusting winds and dry weather.
Even after the flames are extinguished, such massive wildfires pose long-term hazards, such as flash flooding, mudslides and debris flow…
Snowpack across Colorado has been thinning since the 1950s, according to the Environmental Protection Agency, with losses as much as 60% at some measurement sites. Scientists from Colorado State University and the University of New Hampshire project further reductions in snowpack by the end of the century, with losses as high as 30% in some areas.
That said, the northern mountains, including the area of Steamboat Resort, are less vulnerable to decreases in snowpack than southern parts of Colorado, Schumacher said. This is because the weather patterns that can deliver large snowfall are more dependable than farther south, where he described winters as either “boom or bust.”