#Wyoming options limited in #ColoradoRiver #drought effort: Under a federal deadline to commit additional #water to downstream states, Wyoming officials say they can’t get specific about volumes — @WyoFile #GreenRiver #COriver #aridification

A paddler plies the placid waters of the upper Green River, with the Bridger Wilderness of the Wind River Mountains as a backdrop. The Green River is the main tributary to the troubled Colorado River. (Angus M. Thuermer Jr/WyoFile)

Click the link to read the article on the WyoFile.com website (Dustin Bleizeffer):

Wyoming joined the three other Upper Colorado River Basin states this week in telling federal officials they will take on additional water conservation efforts, but cannot commit to sending specific volumes of water to downstream states in 2023.

“We stand ready to participate in and support efforts, across the Basin, to address the continuing dry hydrology and depleted storage conditions,” Upper Colorado River Commission Executive Director Charles Cullom stated in a July 18 letter to the Bureau of Reclamation. “The options the Upper Division States have available to protect critical reservoir elevations are limited.”

The federal government in June asked for firm, voluntary water conservation commitments among all seven Colorado River Basin states that would keep an additional 2 million to 4 million acre feet of water flowing into Lake Powell and Lake Mead in 2023. That’s the estimated volume of additional water necessary to keep the levels at Powell and Mead high enough to continue generating hydroelectricity next year. Wyoming is one of four upper-basin states governed by the Colorado River Compact.

Map credit: AGU

For comparison, the Flaming Gorge Reservoir straddling the Wyoming-Utah border has a storage capacity of 3.8 million acre feet of water.

If unsatisfied with the voluntary commitments, the Bureau of Reclamation and Interior Department are prepared to use their federal authority to implement mandatory water conservation actions, according to Bureau of Reclamation Commissioner Camille Touton. Touton issued the challenge to Colorado River Basin states in June, giving them 60 days to submit their voluntary water savings commitments. States have until Aug. 15 to respond.

But for Wyoming, one of the four Upper Basin states along with Utah, Colorado and New Mexico, it’s impossible to either quantify or guarantee a specific volume of water savings under the ongoing Colorado River Drought Response Operations Plan, according to Wyoming State Engineer Brandon Gebhart.

Mother Nature is the biggest reason behind that, he said. As a headwaters state, Wyoming’s role in the Colorado River system is that of a supplier, and that supply varies wildly depending on seasonal snowfall, evaporation and soil moisture — even more so than volumes of water used by ag producers, industry and municipalities.

“We really are unable to commit to any specific volumes by the deadline [Aug. 15],” Gebhart said. “The [water supply estimating] process requires forecasting data that isn’t available until late winter and early spring of 2023.”

Further, Gebhart added, the federal government lacks the authority to force those with water rights in Wyoming to curtail their water use, and the state is reluctant to do so because it would require coordination among thousands of water rights users. “We would much rather have the water rights users decide how they want to be involved than for us to go in and regulate.”

Flaming Gorge Reservoir on the Utah side near the dam in September 2021. (Dustin Bleizeffer/WyoFile)

Wyoming and other Upper Colorado River Basin states should feel an obligation to do a better job of accounting for their water use compared to seasonal water availability, Great Basin Water Network Executive Director Kyle Roerink said. That would help those states set more specific targets in contributing to the system-wide drought response plan.

“For right now, the response from the Upper Basin states has been ‘hell no, we’re not giving up a drop,’” Roerink said.

Colorado River crisis

The continuing climate change-driven aridification across much of the West has depleted Colorado River reservoirs to historic lows, threatening hydroelectric power generation and water supplies to some 40 million people who rely on the river system. The surface elevation at Lake Powell fell to 3,522 feet in June, the lowest since construction of the Glen Canyon Dam in the 1960s. Water intake ducts at the dam’s hydroelectric power station would no longer function if the lake’s surface level reaches 3,490 feet, according to the Bureau of Reclamation.

Increasing demand for water throughout the southwest combined with climate forecasts suggest the situation will only become worse for those dependent on the river system.

“The conditions we see today, and the potential risks we see on the horizon, demands that we take prompt action.” Interior Department Assistant Secretary Tanya Trujillo told reporters in May.

Boat ramps stretch to the water at Flaming Gorge Reservoir in September 2021. (Dustin Bleizeffer/WyoFile)

The Bureau of Reclamation owns and operates a large complex of reservoirs along the Colorado River and its tributaries that serve as a water banking system. That includes the Flaming Gorge Reservoir on the Green River in Wyoming and Utah. The Green River, the chief tributary to the Colorado River, originates in the Wind River Range, flows to Flaming Gorge Reservoir, then connects with the Colorado River in Canyonlands National Park in Utah.

In June, the Bureau of Reclamation announced it would release an extra 500,000 acre feet of water from Flaming Gorge Reservoir this year, dropping the surface level by an estimated 15 feet sometime in the fall. The agency also plans to withhold 480,000 acre feet of water in Lake Powell, while Colorado River Lower Basin users agreed to increased water conservation measures.

Federal and state officials worry that more drastic measures may be required to maintain critical water levels at Lake Powell and Lake Mead next year and for the foreseeable future.

“Despite the actions taken by the [Bureau of Reclamation], significant and additional conservation actions are required to protect the Colorado River system infrastructure and the long-term stability of the system,” Commissioner Touton testified to the Senate Committee on Energy and Natural Resources in June.

More conservation tools
Rather than committing to sending specific volumes of water downstream, the four Upper Basin states say they need the Interior’s help in pushing Congress to reauthorize the 2014 System Conservation Pilot Project. The program offered payments to water rights users who voluntarily cut back on their normal water diversions.

“[Reauthorization] is a Congressional action,” Gebhart said. “And because [the SCPP program] is voluntary, we don’t know what amount of participation will occur.”

U.S. Sens. John Barrasso (R-Wyoming) and John Hickenlooper (D-Colorado) said they would bring a reauthorization bill to the Energy and Natural Resources Committee this month.

Other elements of the Upper Colorado River Commission’s counter-offer, or “5 Point Plan,” include asking the federal government to fund better water measurement, monitoring and reporting tools. Combined with reauthorizing the SCPP, Wyoming and other Upper Colorado River Basin states can build a more “permanent” program to manage water demand, according to Gebhart and the Wyoming Attorney General’s Office.

Setting up a comprehensive conservation plan is the best Wyoming can offer for now, said Chris Brown, Wyoming Senior Assistant Attorney General for the office’s water division.

“It’s something we can do to try to help the system within the time period that the [Bureau of Reclamation] commissioner asked for,” Brown said. “We’ll set that up and do what we can to try to incentivize reductions in use.”

Committing specific volumes of water savings is “logistically impossible” to do by the Aug. 15 deadline, he added.

Meantime, Gebhart said he and other Wyoming officials will continue to work within Gov. Mark Gordon’s Colorado River Working Group and with all the Colorado River Basin stakeholders in figuring out how Wyoming can help stabilize the river system under worsening conditions.


Dustin Bleizeffer is a Report for America Corps member covering energy and climate at WyoFile. He has worked as a coal miner, an oilfield mechanic, and for 22 years as a statewide reporter and editor primarily… More by Dustin Bleizeffer

West Drought Monitor map July 19, 2022.

#Arizona #Water Leaders Lay Out Plans For Facing The Emerging Crisis In The #ColoradoRiver System — Arizona Department of Water Resources #COriver #aridification

Graphic credit: USBR

Click the link to read the article on the Arizona Department of Water Resources website:

Arizona’s water leaders on July 13 laid out the path forward for contending with the extraordinarily difficult choices facing all of the Colorado River system’s water users over the next several months.

In a sobering presentation to the Arizona Reconsultation Committee (the panel assembled to help develop an Arizona perspective on new operational guidelines for the river system by 2026), Arizona Department of Water Resources Director Tom Buschatzke and Central Arizona Project General Manager Ted Cooke described the unprecedented challenges facing the system currently.

In addition, they gave the ARC members a first glimpse into the negotiations among Colorado River states on how they will contend with enormous water-delivery cutbacks.

Alan Butler of the Bureau of Reclamation provided an analysis of the river system’s current hydrology and an analysis of the enormous volumes of water that must be left in Lake Powell and Lake Mead to protect the system from descending to below critical levels.

Butler told the ARC members that the system currently is at 35 percent of capacity, down from 41 percent of capacity at this time last year. He observed that Lake Mead will almost certainly be in a Tier 2 shortage condition in 2023.

“That continued declining condition is predicted to continue,” said Butler.

On June 14, Bureau Commissioner Camille Touton said at a U.S. Senate committee hearing that the Colorado River system would need between 2-4 million acre-feet of additional conservation in the two reservoirs to achieve stability. Butler emphasized that his analysis of the critical surface levels that needed to be maintained did not suggest specific amounts that each Basin States would need to conserve.

“We wanted to quantify the magnitude of what it would take to keep the reservoirs at those levels, but we’re not attributing that to anyone or any one basin.”

CAP GM Cooke recalled Commissioner Touton’s comments to the Senate in which she observed that the necessary volumes could not be achieved by any one entity, such as agriculture or municipal water providers, or by any one state.

Map of the Colorado River drainage basin, created using USGS data. By Shannon1 Creative Commons Attribution-Share Alike 4.0

She said that “everyone had to participate across the Basin, and that includes Upper Basin and Lower Basin.”

“It doesn’t take much diving into the math to realize that this is the case,” said Cooke.

By itself, he added, Arizona has committed to conserving more than 800,000 acre-feet in the system in 2022 alone, when all the various commitments like the Drought Contingency Plan and the 500+ Plan and volunteer efforts are totaled.

Butler’s presentation illustrated one of the most serious developments affecting the system – the fact that very low volumes of water are making it into the river system despite near-normal volumes of snowpack in the river’s main source of moisture, the Colorado Rockies.

Director Buschatzke laid out for the audience the actions that he anticipates will be needed to stabilize the system.

He particularly recalled Commissioner Touton’s June 14 testimony in which she asserted the federal government’s commitment to protecting the system, even if the Basin States could not come to an agreement among themselves.

“Her answer was, ‘yes, we will protect the system.”

“We’re hearing a consistent story from the United States that they are going to protect the system, that everyone needs to contribute, and that while priorities will be respected to some degree, they are not going to be the outcome at the end of the day.”

With considerable emphasis, Buschatzke also declared he would vigorously oppose any effort to make the “junior” status of most Central Arizona Project water the solution to the Colorado River system’s current crisis:

“We in Arizona are not going to walk out of any room in which an agreed-upon outcome is CAP going to zero. That is not something that Ted and I will ever agree to.

“If they want to force that outcome on us we will deal with those impacts, but we are not going to voluntarily send CAP into the mud.”

(Sen. Mark Kelly Questions Reclamation Commissioner Camille Touton During Hearing On Extreme Drought In The Western United States)

Why nighttime heat [daily low temperature] matters so much: All-time daily temperature records have been smashed in #Colorado this summer, but here’s why the rising overnight minimums are so concerning — @BigPivots #ActOnClimate

Click the link to read the article on the Big Pivots website (Allen Best):

Whew – it was another hot night [July 20-21, 2022], the worst in a string of hot July nights in metropolitan Denver. The temperature, according to my cell phone, did not fall below 80 degrees until 1 a.m. In my office, it was even hotter, approaching 84.

Yes, you are correct. I have no air. I have a full-house fan, which draws colder air in through windows and ushers the hot air out through the attic of this 133-year-old bungalow. To work effectively, night-time temperatures must get down into the 60s. The phone told me that overnight it got down to 74.

Summer nights have been warming. We pay attention to the record highs, and we’ve had some of those. But cooling off at night can make all the difference.

“In general, we know that summer minimum temperatures are rising,” said Peter Goble, a climatologist with the Colorado Climate Center. This summer’s overnight lows so far in 2022 haven’t been setting new high marks – but they’re very, very close.

“It’s not unprecedented but it’s right up there with the all-time maximums (for overnight lows) that have been observed,” he said after checking data for several locations.

For example, Denver’s Central Park Station – this is where the former Stapleton airport was located – had a temperature of 69 the night when supposedly it got only to 74 here at my home/office in Olde Town Arvada. No record – but it was pushing the extreme. Only 12 times have temperatures exceeded 70 degrees.

These night-time hot temperatures serve as a strong reminder of the relatively narrow band of temperatures at which humans can feel comfortable — and function. Older people – I guess that includes me – are less accommodating of both heat and cold. We’re also at more risk.

“It’s not a single hot night that hurts. It’s the accumulation of multiple hot days and nights. That’s where we are right now,” said Nolan Doesken the morning after that hot, hot night. “Heat waves don’t start claiming human lives until they’re three or four days in a row.”

The former Colorado state climatologist, Doesken has a vivid memory of the hottest night on record in Fort Collins, where he lives. He had driven solo that day 1,100 miles from Muskegon, Mich. That’s a grueling drive for anybody, but for Doesken, a lover of all things weather since a child growing up in the Midwest, most notable was the complete absence of clouds.

Doesken has an air conditioner as backup but tries to rely upon a whole-house fan. “When we get down to 62 or 63 overnight, we can be very comfortable with our full-house fan.”

Some people have no air conditioning. Swamp coolers work well in dry climates, but they, too, have their limits.

Elizabeth Babcock, the climate team manager for the city of Denver, reports she weatherized her older home – an imperative for keeping cool temperatures in and hot temperatures out – and installed an evaporative, or swamp, cooler. They can cool the interiors of buildings, but they do a poor job of filtering impurities such as come with wildfire smoke.

The better answer? Air-source heat pumps, which can filter the air while cooling homes in summer and warming them in winter.

“I think we have to be strategic in how we think about cooling technologies,” said Babcock.

Denver, along with the rest of the globe, has been heating up. A 2017 study by the Rocky Mountain Climate Organization found the number of 100-plus days per year had more than doubled in the 21st century. With continued high emissions of greenhouse gases, Denver should expect mid-century high daytime temperatures 2 degrees hotter on average than experienced in El Paso, Texas, in the latter decades of the 20th century.

By century’s end, Denver’s high temperatures will be on par with those of Tucson in recent years, according to the study.

Babcock believes that the nighttime warming temperatures experienced in Denver already make that study look dated. “We are seeing impacts of climate change here today, and we really weren’t built for this new climate.”

In making Denver more resilient to rising temperatures, Denver conducted a study to identify neighborhoods most vulnerable to extreme heat, both day and night.

Vulnerable populations can be identified in various ways, including physical disabilities and age. Children under 5 and those over 70 tend to be most vulnerable. So are people with diabetes. And do they have access to transportation?

Even if transportation is available, the better option is to make homes less vulnerable. “There are lots and lots of reasons that people would not want to leave their homes to go to a cooling shelter,” said Babcock.

See Denver’s heat-vulnerability mapping.

Globeville, which is bifurcated by Interstate 70, is one of Denver’s neighborhoods most vulnerable to extreme heat. Photo/Allen Best

The city is rolling out several programs to enhance resiliency to extreme heat. One will yield 2,000 trees over the next three years in the Westwood, Globeville, Elyria, and Swansea neighborhoods, among the city’s most vulnerable. The trees and plantings along with care will be provided for several years.

Another measure to temper what is called the heat-island effect of a city is a requirement governing roofs of 25,000 square feet or more. Instead of black tar, which absorbs and retains heat, the new roofs must use materials that have greater reflectivity. They should cool off more quickly at night.

The city is also aggressively pursuing electrification to lower emissions, but that also reduces the heat in urban areas by replacing engines that generate heat with electricity. “When you think about things like internal combustion vehicles, they produce a lot of heat. Electrification will temper the heat somewhat.

“We’re looking at all potential tools available to us to address the extreme heat,” Babcock said.

No data are readily available about how many deaths in Colorado can be attributed to heat. Axios this week reported more than 1,900 people had died in Spain and Portugal from the heat there during the preceding week. The Environmental Protection Agency points to some statistical approaches that more than 1,300 deaths occur per year in the United States due to extreme heat. The New York Times reported that 100 million Americans this week were under heat advisories or warnings. That included Austin, the capital of Texas, where temperatures had reached 100 or more for the 40th straight day on Wednesday.

In a June story titled, “How Extreme Heat Kills, Sickens, Strains and Ages Us,” the Times told of research by scientists. “One thing is for sure, scientists say: The heat waves of the past two decades are not good predictors of the risks that will confront us in the decades to come,” the newspaper’s Raymond reported. Their research, he went on, has now focused on the effects on ordinary people.

Like many meteorologists, Doesken was not immediately sold on climate change. The accumulating evidence of hot nights persuaded him. Goble, at the Colorado Climate Center, explains why night-time high temperatures are so important to understand.

“Summertime minimum temperatures do not vary naturally from year-to-year as much as summertime maximum temperatures, or temperatures in other seasons. For this reason, it is easier to spot long-term trends, such as our current warming trend, looking at summertime minimum temperature data,” he explains.

Other times of year, including winter, weather is altogether more variable from day to day and week to week.

In summer, there’s more variability in daytime temperatures than at night. So when we have a marked increase in nighttime temperatures, that is a strong indicator of a warming climate consistent with the theory of global warming.

Theory in this case means not a hypothesis, but rather a cohesive and complex idea that explains much. Einstein’s theory of relatively, for example, remains intact after a century of people looking for flaws. Similarly, theory of global warming explains much of what is being observed.

“The easiest way to identify long-term trends is in summer nighttime temperatures,” says Goble.

“We are seeing significantly warmer night-time minimum temperatures in summers of the 21st century as compared to the 20th century.”

ABOUT THE CHART: It comes from the National Weather Service, an agency within the National Oceanic and Atmospheric Administration. One of the meteorologist in Boulder explains that the chart was assembled using a gridded data set from 500 stations, of which only 180 are currently active. See more at this website, and if you really want to get into the weeds, you can go to this place that explains the computation in greater detail.

SEE ALSO: A story on Climate Central report on cities, extreme heat and humidity: https://www.denverpost.com/2016/07/14/colorado-summers-getting-hotter-stickier/