#Climate variability normal, but extent of warming during spring #runoff is not — The Mountain Town News @MountainTownNew @ActOnClimate

From The Mountain Town News (Allen Best):

Warming temperatures but especially so during spring months

In Pennsylvania, the groundhog known as Punxsutawney Phil saw no shadow this year. That is supposed to portend an early spring.

In the Rocky Mountains, early springs have been coming no matter what. This was a cold winter in many places, but on average the climate has been warming for several decades. It’s sure to get much warmer yet.

A case in point is Colorado’s North Park, headwaters of the North Platte River but a short distance from the headwaters of the Colorado River and also the Steamboat ski area.

There, according to Dr. J.J. Shinker, an associate professor from the University of Wyoming, the temperature overall has increased 1.44 degrees Celsius (2.6 degrees Fahrenheit) since 1909.

The Eagle River roils with spring runoff in June 2011 near Edwards, Colo. Photo/Allen Best

But warming during the spring months of March, April, and May has been disproportionate, rising almost 4 degrees Fahrenheit (2.21 degrees C) on average since 1909.

“That’s a lot of warming in a short period of time,” she told members of the Colorado Water Congress at a recent conference. She also pointed out that warming at high elevations has been disproportionately greater than the global average.

(But Jeff Lukas of Western Water Assessment, the lead author of “Climate Change in Colorado,” the 2014 synthesis report sponsored by the Colorado Water Conservation Board, points out that “there is no robust and consistent evidence that higher-elevation regions in Colorado are warming at a different rate than lower-elevation regions.”

But of disproportionate warming during spring, there is no dissent. And that produces earlier runoff in the North Platte and other rivers in Colorado. On average, runoff occurs five days earlier for every degree Celsius in warming.

This matters to water managers, who try to ensure the irrigation ditches still have enough water come August and September. It also matters to mountain resorts as warming springs shrink the backend of ski season.

But everybody should be concerned for two more reasons, says Shinker. First, the worst droughts we’ve seen, the worst on record since Eurosettlement about 150 years ago, don’t come close in depth and intensity to those of the past. Forest fires of the past were also giant affairs.

This was part of natural variability. But now there is the overlay of what might be called unnatural variability, this overlay caused by human forcing of the climate.

“The warming that we are seeing is occurring at a rate that is outside the range of natural variability,” Shinker said in an interview after her talk to Colorado water managers. “And it’s occurring as a result of the greenhouse gases that result from human activity.”

Paleoclimatologists can tell much about shifting climates of the past 12,000 years by studying high mountain lakes. Consider Emerald Lake, which is in Colorado’s Sawatch Range, near the trailheads to the state’s two highest mountains, Elbert and Massive. Scientists studying lake sediments and other clues have documented shorelines that a millennium ago were much lower. The droughts then lasted for decades, even hundreds of years, what are called megadroughts.

Lake of the Woods, which is located in Wyoming along the Continental Divide south of Jackson Hole, also offers evidence deciphered by scientists of a megadrought 5,200 years ago.

The point, said Shinker, is that natural variability has always occurred in the interior West. So, too have, extreme events, such as the wildfires that accompanied a megadrought in North Park about 2,000 years ago.

In the Colorado River Basin, scientists have reached much the same conclusion. Undeniably, there have been several hard drought years since 2000. But Brad Udall of Colorado State University and other scientists have concluded that it’s not a drought as conventionally understood. Rather, rising temperatures have begun causing more evaporation and transpiration, resulting in less water getting downstream.

That doesn’t mean conventional climatic forces don’t have swagger. From her post in Wyoming, Shinker studies what causes natural climatic variability in the interior West, such as movement of the polar jet stream north and south. But now there’s an overlay to those natural climatic variations, one created by human activities.

A dry desert with its history surrounded by stories of water — The Palm Springs Desert Sun

From The Palm Springs Desert Sun (Tracy Conrad):

Despite its designation as a desert, the Coachella Valley is blessed with water. The very names associated with the most prominent places and businesses in the desert, such as the Oasis Hotel, Mineral Springs Hotel, Deep Well, Indian Wells, Palm Springs, Snow Creek, and Tahquitz River Estates, all conjure up pretty images of water.

But the early story of desert water is more utilitarian than picturesque: it quite literally can be seen as a history of ditches.

More than a century ago a prescient and patient few understood that water was the most precious of all resources in such an arid region. Hydrology was the purview of engineers, and the first way to move water was in ditches. The most famous Southern California water scheme, made to ensure a reliable water supply for burgeoning Los Angeles, came at the cost of turning a once fertile pasture surrounding a lake situated 200 miles away from LA into a dust-polluting salt flat the size of San Francisco. But here in the natural desert, there were visionaries thinking about using local water and building their own infrastructure to deliver it.

As early as 1830, the local Cahuilla people brought water from Tahquitz Creek to their village by simple ditches constructed for irrigation. The flow was seasonal and subject to diversion and clogging. Those at the end of the line seldom got water.

In 1887, early white settler John Guthrie McCallum formed the Palm Valley Water Company and began the construction of a stone-lined irrigation ditch to traverse what is variously reported as 16, 17, or 19 miles of desert between the San Gorgonio Pass and Palm Springs to carry the flow of the Whitewater River (whatever the actual distance, it was an astonishing accomplishment).

McCallum also developed the waters of Chino Canyon for irrigation, and hoped to prosper by raising figs, grapes, olives and apricots earlier than coastal farmers. There were unauthorized diversions of the sluice and many disputes — exacerbated by a flash flood that destroyed the canal — followed by more than a decade of drought during which most of any civilization in the Coachella Valley perished. By 1905, when the drought finally ended, actual lack of water and legal disputes over water rights left very few Cahuilla and even fewer white settlers in the region…

In 1927, Alvah Hicks acquired the Palm Valley Water Company with a loan from Mr. O’Donnell, reorganized it and changed its name to the Palm Springs Water Company. Hicks sourced water from Snow Creek and Falls Creek, each with their own conduits, while presumably improving water pressure up the hill. Alvah’s sons Harold and Milton Hicks took over the stewardship of the company from their father, expanding pipelines and supplies. Alvah prided himself on building for future capacity and his sons carried on that forward-thinking practice. Therefore, in addition to the flumes, wells were drilled to tap into the aquifer — the vast lake beneath the valley floor. Ironically, abundant water had been just below the ground for millennia — a legacy of the prehistoric Lake Cahuilla that had once inundated much of the valley…

[P.T] In 1927, Stevens formed the Whitewater Mutual Water Company and supplied irrigation water from the Whitewater River for residential and agricultural use. He had his own system of pipes and ditches that would divert the river, while allowing for intermittent flow from the river. Tom O’Donnell owned shares in Whitewater, which irrigated his golf course…

At the south end of the Coachella Valley, there was an even more ambitious ditch-digging project, rivaled only by Mulholland’s Los Angeles aqueduct. Starting in 1900, the California Development Company constructed hundreds of miles of irrigation ditches and canals to bring water from the Colorado River to the arid desert and create fertile farmland out of the Salton sink. At first the effort worked, but it lasted for only a few years until the silt-laden Colorado water clogged the canal.

After a prodigious rainfall in 1905, a breach in the walls of the canal caused the entirety of the river to flow into the sink for the next two years while workers frantically worked on repairs. This tinkering with nature resulted in the Salton Sea.

@USBR: Aspinall Unit Forecast for Spring Operations: Current projected inflow to Blue Mesa Reservoir = 925,000 acre-feet

From email from Reclamation (Erik Knight):

The April 1 forecast for the April – July unregulated inflow volume to Blue Mesa Reservoir is 925,000 acre-feet. This is 137% of the 30 year average. Snowpack in the upper Gunnison River basin is currently 132% of average. Blue Mesa Reservoir current content is 259,000 acre-feet which is 31% of full. Current elevation is 7440 feet. Maximum content at Blue Mesa Reservoir is 829,500 acre-feet at an elevation of 7519.4 feet.

Black Canyon Water Right
The peak flow and shoulder flow components of the Black Canyon Water Right will be determined by the May 1 forecast of the April – July unregulated inflow volume to Blue Mesa Reservoir. If the May 1 forecast is equal to the current forecast of 925,000 acre-feet of runoff volume, the peak flow target will be 6,513 cfs for a duration of 24 hours. The shoulder flow target will be 915 cfs, for the period between May 1 and July 25. The point of measurement of flows to satisfy the Black Canyon Water Right is at the Gunnison River below Gunnison Tunnel streamgage at the upstream boundary of Black Canyon of the Gunnison National Park.

Aspinall Unit Operations ROD
Pursuant to the Aspinall Unit Operations Record of Decision (ROD), the peak flow and duration flow targets in the lower Gunnison River, as measured at the Whitewater gage, will be determined by the forecast of the April – July unregulated inflow volume to Blue Mesa Reservoir and the hydrologic year type. At the time of the spring operation, if the forecast is equal to the current forecast of 925,000 acre-feet of runoff volume, the hydrologic year type will be set as Moderately Wet. Under a Moderately Wet year the peak flow target will be 14,350 cfs and the duration target at this flow will be 10 days. The duration target for the half-bankfull flow of 8,070 cfs will be 20 days. The criteria have been met for the drought rule that allows half-bankfull flows to be reduced from 40 days to 20 days.

Projected Spring Operations
During spring operations, releases from the Aspinall Unit will be made in an attempt to match the peak flow of the North Fork of the Gunnison River to maximize the potential of meeting the desired peak at the Whitewater gage, while simultaneously meeting the Black Canyon Water Right peak flow amount. The magnitude of release necessary to meet the desired peak at the Whitewater gage will be dependent on the flow contribution from the North Fork of the Gunnison River and other tributaries downstream from the Aspinall Unit. Current projections for spring peak operations show that flows in the Gunnison River through the Black Canyon could be over 7,500 cfs for 10 days in order to achieve the desired peak flow and duration at Whitewater. With this runoff forecast and corresponding downstream targets, Blue Mesa Reservoir is currently projected to fill to an elevation of around 7500 feet with an approximate peak content of 660,000 acre-feet.

Aspinall Unit dams

#Snowpack/#Runoff news: @Northern_Water declares a 70% quota for the 2019 season #ColoradoRiver #COriver

Lake Granby spill June 2011 via USBR. Granby Dam was retrofitted with a hydroelectric component and began producing electricity earlier this year as water is released in the Colorado River.

From The Loveland Reporter-Herald (Sam Lounsberry):

Unit owners of the Colorado-Big Thompson project, which delivers Colorado River water from the wet Western Slope to the dryer Front Range, will get 70% of their quota this year, according to a Northern Water news release.

The 70% allocation means that a farmer who owns 10 acre-feet of Colorado-Big Thompson water will get seven in a year, with the remaining three kept in storage for use in dry years…

In wet years like this one, Northern sometimes downsizes the quota of Colorado-Big Thompson water distributed, since native streams can be full enough to provide farmers late-season growing supply, which provides Northern a storage opportunity for use in dry years.

But the move to boost the Colorado-Big Thompson quota from 50% — the level normally set at the start of Northern’s water year in November just to get users through the winter so snowfall can inform spring allocation rates — ensures farmers will have a more flexible late growing season.

The quota increases available Colorado-Big Thompson water supplies by 62,000 acre-feet from the initial 50% quota made available in November…

The snow-water equivalent mark for the Upper Colorado Basin is 120% of the normal median as of Thursday, according to the U.S. Bureau of Reclamation, with snowpack levels in other river basins across the southwest at even higher marks. But KUNC and The Aspen Times reported this year that despite the good snowfall this winter, officials predict spring runoff won’t be enough to replenish reservoirs across the southwest, because years of drought have left dry soil that sucks up extra drops.

“Modeled soil moisture conditions as of November 15th were below average over most of the Upper Colorado River Basin and Great Basin,” the Colorado Basin River Forecast Center stated in its April 1 report. “In the Upper Colorado River Mainstem River Basin, soil moisture conditions were below average in headwater basins along the Continental Divide, and closer to average downstream.”

Water from the Colorado-Big Thompson project supplements other sources for 33 cities and towns, 120 agricultural irrigation companies, various industries and other water users within Northern Water’s 1.6 million-acre service area, across parts of eight counties, the Northern release said.

Westwide SNOTEL basin-filled map April 11, 2019 via the NRCS.

#ColoradoRiver #Drought Contingency Plans enabling legislation a win for #Colorado — @SenatorBennet @SenCoryGardner #COriver #DCP #aridification

Both science and science fiction say the future is going to be hotter, drier and dustier, and this silt-fall in upper Lake Powell in September 2018 captures the trend. Photo credit: Brent Gardner-Smith/Aspen Journalism

From The Fort Morgan Times (Brian Porter):

Once signed into law, the legislation will authorize the implementation of the Drought Contingency Plan agreements forged between the seven Colorado River Basin states and Native American tribes.

“Tens of millions of people in the western United States rely on the Colorado River to provide water for agricultural, municipal, and consumptive use, as well as support for our growing recreation economy,” Gardner said.

The Drought Contingency Plan enjoys widespread support in Colorado, including from the state and multiple Front Range and Western Slope water utilities.

“The Colorado River is the lifeblood of our economy, but in recent years we’ve experienced some of the worst drought conditions in centuries,” Bennet said. “Passing the Drought Contingency Plan is a win for the millions of people across the West who rely on the Colorado River.”

[…]

“Following the leadership of Coloradans and communities across the seven affected states, we are now one step closer to countering drought, addressing climate change, and strengthening Colorado’s agricultural and outdoor recreation-based economy,” Bennet said.

As The #ColoradoRiver Basin Dries, Can An Accidental Oasis Survive? — KUNC #COriver #aridification

La Ciénega de Santa Clara via YouTube

From KUNC (Luke Runyon):

CIÉNEGA DE SANTA CLARA, MEXICO: Juan Butrón-Méndez navigates a small metal motorboat through a maze of tall reeds here in the Mexican state of Sonora. It’s nearing sunset, and the sky is turning shades of light blue and purple…

Butrón-Méndez lives nearby and works for the conservation group Pronatura Noroeste as a bird monitor…

He cuts the motor in an open stretch of water he calls the “scary lagoon,” ringed by tall grasses that rise from the thigh-high water. Without the boat’s droning hum, coastal birds appear over the reeds, and come in for a water landing.

American coots, with their white bills and dark grey feathers, cackle as they swim. They’re interspersed among broad-winged, yellow-beaked pelicans. Other birds, just silhouettes, dart along the surface, skimming for insects before dark. There’s no sign of them tonight, but several species of threatened or endangered marsh birds — like the Ridgway’s rail — call this place home too…

Butrón-Méndez has explored this wetland since its creation, watching over the course of decades as the shape-shifting oasis was born.

“Water started to flow to this place in the 1970s. I would walk around here without having to worry about getting wet,” Butrón-Méndez said though a translator. “If there wasn’t water, it’s a dry place.”

He’s been called the Ciénega’s patron saint, able to rattle off its history and the names of the birds, fish and mammals that live here.

The wetland is fed by a concrete canal that removes drainage water from American farms across the border in Arizona. The canal is called the MODE — Main Outlet Drain Extension. The salty runoff inadvertently created this oasis in the middle of the Sonoran desert, a perfect stopover for migratory birds on their journey along the Pacific coast…

But there’s a problem. As the Colorado River basin heats up and dries out like climate projections predict, Butrón-Méndez is concerned people will stop thinking of the water that flows to the wetland as waste, find a way to use it and, in turn, harm the Ciénega…

Wasted water

The Ciénega was born in 1977 when the U.S. began draining salty agricultural runoff to the Santa Clara slough, near the Gulf of California. Years prior, the U.S. agreed not to send degraded water to Mexico, a near-constant tension between the two countries since they signed their first Colorado River treaty in 1944.

In a 1973 agreement called the “Permanent and Definitive Solution to the International Problem of the Salinity of the Colorado River,” President Richard Nixon’s administration agreed to a limit on how salty water would be at when delivered at the U.S.-Mexico border.

To keep the river from becoming loaded with salt, someone had to devise a way to keep the farm runoff from ending up in it. That’s how the MODE canal came to be. After irrigating lettuce fields and date palms in salty soil near Yuma, Arizona, the concrete-lined MODE would take the leftover water across the border close to the Pacific Ocean to dispose of it.

No one meant to create a haven for birds and other wildlife in the dried-out Colorado River delta in the process. But by sending about 100,000 acre-feet of water annually out into the desert, that’s what happened…

The wetland does have some protections. The Mexican government has designated the Ciénega as a Biosphere Reserve in the Colorado River Delta. It’s also been recognized for having “great ecological significance” by the Ramsar convention, an intergovernmental treaty on the value of wetlands. If the U.S. were to run the Yuma Desalting Plant it would likely trigger a reconsultation of previous agreements between the two countries.

Statement by @USBR Commissioner Brenda Burman on historic legislation to implement #Drought Contingency Plans #ColoradoRiver #COriver #DCP #aridification

The Colorado River below Glen Canyon Dam. Photo credit: USBR

Here’s the release from the Bureau of Reclamation (Theresa Eisenman):

I’m pleased that collaborative efforts among the seven Colorado River Basin states, local water agencies, Tribes, non-governmental organizations, Mexico and the Department of the Interior to reduce risk on the Colorado River are succeeding. I applaud Congress for taking prompt action on implementing legislation for the Drought Contingency Plans. This brings us one step closer to supporting agriculture and protecting the water supplies for 40 million people in the United States and Mexico. Working together remains the best approach for all those who rely on the Colorado River.

Hoover Dam. Photo credit: Air Wolfhound Flickr Creative Commons

From The Arizona Star (Tony Davis):

Legislation for the drought contingency plan aimed at propping up Lakes Mead and Powell unanimously cleared the House and Senate Monday and Tuesday, respectively. The bill now heads to President Trump for his signature.

The plan calls on the Lower Colorado River Basin states of Arizona, California and Nevada to conserve up to 1.2 million acre-feet of the 7.5 million acre-feet to which they have a right between now and 2026. The cuts will kick in at small amounts almost immediately and will escalate when Lake Mead drops low enough.

Arizona, whose $4 billion Central Arizona Project will take the first cuts during a Colorado River shortage, would lose 192,000 acre-feet of CAP water at first. (One acre-foot is enough water to serve four Tucson households for a year.)

When Lake Mead drops below 1,075 feet, which could happen by 2021, the CAP would lose nearly one-third of its supply, or 500,000 acre-feet. When Mead hits 1,025 feet, the CAP would lose more than 700,000 acre-feet.

The plan is aimed at delaying the time when the two reservoirs will drop so low that it will be difficult or impossible to get water and electric power from them.

Rep. Raúl Grijalva, a Tucson Democrat whose bill is the one headed to the White House, praised its passage but warned in an interview that it’s only an interim step.

The seven Colorado River basin states must soon start work on revising guidelines for managing the river that were approved in 2007 and expire in 2026…

This was “a remarkable chapter in the long story of securing Arizona’s water supplies,” said Arizona Department of Water Resources Director Tom Buschatzke.

In congressional testimony last month, Buschatzke acknowledged the plan isn’t a permanent solution: “We recognize that more must be done by the states to prepare for a drier future.”