Extreme weather? Yes, and the events were interrelated: The convergence of hot and dry, flash floods and bad air were manifestations of a fast-changing #climate in #Colorado and beyond — Big Pivots

From Big Pivots (Allen Best):

Heat waves in June and again in July. Monster wildfires on the West Coast that made the air in Denver, Salt Lake City and Cheyenne unhealthy. Then fast floods that produced debris flows, blocking Colorado’s major east-west artery, Interstate 70 through Glenwood Canyon.

They’re separate but related, said Western Water Assessment’s Seth Arens in a Nov. 18 review of the year’s extreme weather events in Colorado, Wyoming and Utah. He called them a convergence of climate hazards.

“These are related; they are not independent,” he said.

Arens described the concept of compound hazards, where the occurrence of one hazard can create conditions for another hazard.

“None of these climate hazards act in isolation and many of them occur with one another,” said Arens, a research scientist based in Salt Lake City.
For example, extreme temperatures and low precipitation lead to drought, which begets increased wildfire risk. The wildfires produce poor air quality. And after the fires, there’s an increased risk of flash floods.

We’re talking visions of Armageddon here—and, at least until the smoke disappeared in September, it seemed that Colorado had arrived in perdition.
Most of the attention about the heat dome of June focused on the West Coast, and rightfully so. Temperatures of 116 in Portland? People literally baked to death in uncooled apartments.

But it was hot in Utah, Colorado and Wyoming, too. Arens said he narrowed his study of temperature records to places with records of at least 50 years. Even so, he found many all-time records and dozens of daily records. On just one day, June 15, Arens found that 79% of daily temperature records in Utah, 53% in Colorado, and 83% in Wyoming were broken. And so it went for two more days before the heat relented.

In July, more records were set, including an all-time record in Grand Junction of 107 degrees. Utah’s all-time record of 117 degrees was tied at St. George. Later in July, all-time high temperatures were set in three Wyoming tow and cities, the highest being 109 degrees in Weston.

Colorado Basin Forecast Center Drought Monitor map November 30, 2021.

Heat devoid of precipitation equals drought. These Western states have had that. Much of the focus has been on the Colorado River Basin.

Runoff in the Colorado River during water year ending October 2021 was 50% of average. Flows into Lake Powell were 28% of median.

In August, Powell reached the lowest elevation since it began filling after completion of the Glen Canyon Dam in 1963. It’s now less than 30% of capacity. That puts it at 157 feet below full pool.

The Bureau of Reclamation, in its two-year projections, estimates the river will drop another 20 feet by spring 2022. Already, there are questions of when the reservoir level will drop below what is called minimum pool, the least amount of water needed to be able to produce electricity. That could happen by early 2023.

Might a big snow year boost water levels in Powell, averting the chain reaction of problems? Perhaps, although Arens offered little encouragement. With the La Niña weather pattern, the odds again are for the Colorado River Basin receiving below-average snowfall.

Weather prediction has a big gap, Arens added. Weather can be predicted with some confidence beyond two weeks, and the climate can be predicted after about 9 years. But between, not much can be said with confidence.

Back to last summer: The air quality was again miserable, approaching the air quality index of 200 in Salt Lake City on July 12. In Denver it was 192. These are all levels where even healthy people are advised to stay indoors. It was marginally better that day in Cheyenne, at 119.

Along the Wasatch Front of Utah, Salt Lake City exceeded the EPA standard for ozone air quality 23 days and Ogden 16 days. In Colorado, Denver exceeded the limit 25 days, Boulder 28, and Colorado Springs 20.

Colorado Department of Transportation
CDOT crews continue clearing mudflow from Interstate 70 in Glenwood Canyon July 2021 — Colorado Department of Transportation

Then there were the flash floods and mudslides. The torrential rains were not everywhere, but in places they sent rocks and mud rushing and tumbling down onto highways. The most notorious was in Glenwood Canyon, where the hillsides were burned last year in the 32,631-acre Grizzly Gulch fire.

These big rains had some beneficial effect, too. Soil moistures recovered, meaning the melting snow next spring will not automatically get sopped up like an absorbent paper towel. Arens also noted that rainstorm had a satisfying result in a Glen Canyon side canyon where the receding waters of Powell had left 18 to 20 feet of silt.The storm sent all the silt downstream, revealing parts of the canyon that David Brower had known.

USBR launches new prize competition to improve #snowpack water forecasts

Here’s the release from the Bureau of Reclamation (Peter Soeth):

The Bureau of Reclamation is launching a new prize competition for improved snowpack water forecast techniques throughout the West. Developing better techniques to determine the amount of water stored as snowpack provides water managers more accurate information to make better water management decisions.

This competition is divided into two tracks. In track one, participants develop a model and calibrate it using historical information. The effectiveness and accuracy of the test model will be evaluated during the winter and spring using real-time snowpack measurements. For track two, models in the first track are eligible to submit a report that discusses their solution and approaches to solving the problem in track one.

Reclamation is partnering with Bonneville Power Administration, NASA – Goddard Space Flight Center, U.S. Army Corps of Engineers, USDA – Natural Resources Conservation Service, U.S. Geological Survey, National Center for Atmospheric Research, DrivenData, HeroX, Ensemble and NASA Tournament Lab.

To learn more, please visit https://www.usbr.gov/research/challenges/swe.html.

Reclamation conducts prize competitions to spur innovation by engaging a non-traditional, problem-solver community. In the past six years, it has awarded more than $4 million in prizes through 29 competitions. Please visit Reclamation’s Water Prize Competition Center to learn more.

Snowcast Showdown

The message from scientists on #Colorado’s lack of snow so far: Don’t panic — Colorado Public Radio #snowpack #ENSO

Westwide SNOTEL basin-filled map December 7, 2021 via the NRCS.

From Colorado Public Radio (Corey H. Jones):

Last week, a blizzard warning was issued for the mountains — of Hawaii. But as the tropical state dealt with flooding and high winds, Colorado has been pretty bone-dry. Denver has set a modern-day record and gone nearly 230 days without any measurable accumulation. Fortunately, it seems like that record’s days are numbered with a winter storm expected later this week.

After nearly two weeks of mostly dry conditions, snow fell in the high country last night [December 6-7, 2021]…

What do we know about the potential for snow?

The reality is there’s no way to tell what’s in store for the rest of the season. Meteorologists aren’t able to forecast conditions month-to-month, however they do know we are experiencing a La Niña winter.

“That generally favors above-average snowfall for the northwest, from Idaho to British Columbia,” [Joel] Gratz said. “But La Niña doesn’t help or hurt us in Colorado much.”

That’s because we’re on the edge of that climate pattern. Big snowstorms along the Front Range — especially in the spring — are not common with La Niña. Gratz said those are more frequent during El Niño seasons.

But the state is also contending with the effects of climate change.

“While we will still get these winter storm patterns and we will still get snow and cold, we are just getting an increasing frequency of these warm anomalies as well,” assistant state climatologist Becky Bolinger told Colorado Matters.

The good news is there’s still plenty of time for Colorado to catch up. Our state usually sees its deepest snowpack in April.

#Snowpack is off to a poor start in the West, bad news amid widespread #drought — The Washington Post

From The Washington Post (Becky Bollinger):

…the snow season usually starts in October in the Rocky Mountains. By the end of November, snow depth on the Cascades, Sierra Nevada, and eastward to the interior Rockies typically ranges from 2 inches at lower elevations to over 20 inches on the highest elevations.

So what have we seen this year? Unfortunately, not much.

The lackluster snowpack is particularly worrisome amid widespread drought in the region — 94 percent of the West is experiencing drought, and many lakes and reservoirs are at historically low levels. A healthy snowpack this winter could help replenish water levels during the spring melt season -— but if snowpack is limited, deficits will grow.

West Drought Monitor map November 30. 2021.

Current conditions

Warm and dry conditions this fall have led to significant snowfall deficits across the western United States. November was warmer than average, and precipitation was below average everywhere except Washington state, which had a string of storms that caused major flooding.

The National Weather Service reported high elevation snowfall lagging behind by 10 to 20 inches last month…

Every basin in the west is below normal, ranging from as little as 2 percent of normal on the Lower Colorado in Arizona to 81 percent of normal for the Upper Columbia in Washington.

Every basin in the West is below normal snow water equivalent. (USDA Natural Resources Conservation Service )

There’s still time

It’s a pretty bleak picture for the start of winter. The bad news is that early season snowpack is an important contribution to the peak snowpack. The good news is that 1) we’ve got a lot of time left, and 2) we can still make up these deficits…

One factor that can affect the region’s winter precipitation is the current La Niña, which is likely to continue through the winter and into the spring. While it’s not always a perfect relationship, we tend to see above-average snowfall in the northwest and below-average snowfall in the southwest during La Niña winters.

If this pans out, the Pacific Northwest and northern Rockies are more likely to get average peak snowpack, but the southern basins would more likely peak below average.

One other challenge to contend with is the temperature outlook. The Climate Prediction Center’s seasonal outlook calls for a greater chance of above-average temperatures for Utah, Colorado and to the south. Above-average temperatures for the lower elevation areas would increase the likelihood of melting, and could also result in earlier and lower peak snowpack. The Pacific Northwest is expected to see below-average temperatures…

With the La Niña and temperature forecasts, the odds are better for Washington, Oregon, Idaho and Montana to have a decent winter, even after a poor start. Northern California, the Great Basin, Wyoming, and the northern reaches of Utah and Colorado could also recover. The areas that are likely to be in the worst shape in the spring would be the central and southern mountains of Utah and Colorado and the rest of the Southwest.

It’s still early enough in the season for things to turn around, however, so let’s all hope for some holiday magic in the form of snowflakes!

Becky Bolinger is the assistant state climatologist for Colorado and a research scientist at Colorado State University.

Douglas County considering Renewable Water Resources plan to export San Luis Valley #water: RWR needs to find a customer to move its proposal forward — The #AlamosaCitizen #RioGrande

The northern end of Colorado’s San Luis Valley has a raw, lonely beauty that rivals almost any place in the North American West. Photo/Allen Best

From The Alamosa Citizen (Chris Lopez):

FOR an initial payment of $20 million Douglas County can become a partner of Renewable Water Resources in its plan to export approximately 20,000 acre-feet of water per year from the San Luis Valley, according to an RWR proposal to the Douglas County Commissioners.

In its proposal to Douglas County, RWR said it currently owns approximately 9,800 acres in the San Luis Valley and has options to purchase an estimated 8,000 additional acres. “The Parties will enter into one or more agreements (the “Contract(s)”) governing the adjudication of approximately 22,000 acre feet of water per year (the “Water Rights”) in Water Division No. 3 (the “Water Case”),” according to the terms of agreement presented to Douglas County.

Download the proposal.

The proposal establishes terms of value for the water rights that Douglas County would own and how it would get a fixed per annual acre-foot rate below current water market rates that other Front Range communities are paying.

“In consideration for the Initial Payment, the Purchase Price for the water rights will be fixed at $18,500.00 per annual acre foot. At that Purchase Price, the Water Rights would be substantially below their current market value, especially for trans-basin water that can be used to extinction. Currently, metro districts and other water service providers in the Colorado Front Range are acquiring water rights for more than $40,000-$50,000 per acre foot for senior rights. With an early investment in RWR, the County can take a leadership role in securing renewable water rights at a significant discount.”

The three Douglas County Commissioners are split on the proposal, based on interviews Alamosa Citizen conducted Tuesday with the county commissioners…

Douglas County has been seeking community input on how to spend $68.2 million of federal funding received through the American Rescue Plan Act. Securing additional water rights to meet its growth is one of the priority areas Douglas County has identified for the federal funding.

Douglas County will host a Town Hall on Thursday to hear from residents on how to prioritize spending of the American Rescue Plan Act. The water rights proposal from RWR is one of the proposals expected to be discussed at the meeting…

Renewable Water Resources needs to find a customer like Douglas County to move its proposal forward. The plan relies on drawing water from the Upper Rio Grande Basin and exporting it to the Front Range. Without an identified end user for the exportation and sale of the water, RWR can’t file its plan in Colorado Water Court.

If Douglas County moves ahead with RWR, State Sen. Cleave Simpson of Alamosa said RWR would need to acquire the water rights and then file in district water court a change to the water rights decree to go from agricultural use to municipal use. He said land RWR owns doesn’t have irrigation well water rights and that RWR would need to buy wells and well permits for its exportation plan…

Simpson has met with the commissioners. He said that Douglas County thinking it can use money from the federal American Rescue Plan Act for the RWR proposal is a twist he didn’t see coming.

“I think it’s unconscionable to use those federal dollars to diminish one community in support of another community,” he said. In addition to representing the San Luis Valley in the Colorado Senate, Simpson is the general manager of the Rio Grande Water Conservation District, which is leading the opposition to the RWR plan.

Read more of Alamosa Citizen’s journalism on the Rio Grande Basin and the RWR project:

DAY 1: The threats ahead
DAY 2: A battle over water exports
DAY 3: Water-saving alternative crops

October aquifer reading causes concern

Drought, land development take toll on the Valley’s natural habitats

Valley water use in a delicate balance

Denver Basin Aquifer System graphic credit USGS.