#Colorado-Big Thompson Project operations update #ColoradoRiver #COriver #aridification

From email from Reclamation (Brittany Jones):

The Bureau of Reclamation will increase diversion of Colorado River water to Horsetooth Reservoir at midnight tonight. The change will require a decrease in the Big Thompson River diverted for power generation at Olympus Dam.

Reclamation is currently releasing 125 cfs to the Big Thompson River from Olympus Dam. The flow will increase to 265 cfs beginning tonight. Our current forecast indicates that runoff into Lake Estes will substantially increase over the next week. It is possible the Olympus Dam required release to the Big Thompson River will exceed 600 cfs.

Aerial view of Lake Estes and Olympus Dam looking west. Photo credit Northern Water.

@USBR: Aspinall Unit Spring Operations update

Questions simmer about #LakePowell’s future as #drought, #climatechange point to a drier #ColoradoRiver Basin — @WaterEdFdn #COriver #aridification

From the Water Education Foundation (Gary Pitzer):

Western Water in-depth: A key reservoir for Colorado River storage program, Powell faces demands from stakeholders in upper and lower basins with different water needs as runoff is forecast to decline

Lake Powell, behind Glen Canyon Dam, shows the effects of persistent drought in the Colorado River Basin. (Source: U.S. Bureau of Reclamation)

Sprawled across a desert expanse along the Utah-Arizona border, Lake Powell’s nearly 100-foot high bathtub ring etched on its sandstone walls belie the challenges of a major Colorado River reservoir at less than half-full. How those challenges play out as demand grows for the river’s water amid a changing climate is fueling simmering questions about Powell’s future.

The reservoir, a central piece of the storage program for the Colorado River, provides water, hydropower and recreation to millions of people. It was designed to ensure that Wyoming, Colorado, Utah and New Mexico can meet their legal obligation to let enough water pass to Arizona, California and Nevada, as well as supplying water to Mexico.

But persistent drought in the Colorado River Basin over the last 20 years and the need to keep Lake Mead, Powell’s twin reservoir downstream, from reaching critically low levels have left Lake Powell consistently about half-full. Some environmental advocacy groups, aiming to restore Glen Canyon, have called for the dam’s decommissioning.

Water managers say that’s unlikely, given Lake Powell’s key role in meeting downstream obligations and the interest of some upstream who hope to tap its waters. Recent studies point to warmer and drier conditions ahead, with reduced runoff into the river. A rewrite of the river’s operating guidelines is on the horizon, and already there is talk about how those guidelines could affect Powell.

Lake Powell and Lake Mead currently adhere to an operations protocol that determines release volumes from Lake Powell to Lake Mead and how Lower Basin water users enjoy the benefits of surplus conditions or the shared sacrifice of delivery cuts during shortage. The rules for these scenarios are found in the 2007 Interim Guidelines, the 2019 Drought Contingency Plans and international agreements with Mexico.

Chief among the Guidelines’ provisions is better coordination of the operations of Lake Powell and Lake Mead each year.

As key stakeholders prepare to forge the next set of management guidelines that will update those from 2007, there may be a reassessment of Lake Powell’s operations so that it can take on the coming challenges.

“I think an honest and thorough look into the future of Lake Powell is absolutely warranted,” said Matt Rice, director of American Rivers Colorado Basin Program.

Rice, part of a February forum on the future of Lake Powell, said the crisis wrought by the coronavirus pandemic shows how rare “black swan” events can emerge and shatter existing management plans, such as those for watersheds.

The dry conditions have prompted Colorado River water agencies to undertake unprecedented, collaborative efforts to ensure water supplies are not disrupted. In Las Vegas, for instance, rebates to homeowners by the Southern Nevada Water Authority have converted 193 million square feet of thirsty grass lawns into water-efficient landscaping.

Staying ahead of future crises is critical, and officials are informally discussing the parameters of the next set of guidelines. How those talks affect future water levels at Lake Powell and Lake Mead will be significant.

A Reliable Lake Powell

Conditions on the river are never static. In some years, a large snowpack produces voluminous runoff, but the science is showing a pattern of decreased flow from tributaries into the mainstem Colorado River. Earlier this month, the National Oceanic and Atmospheric Administration’s Colorado Basin River Forecast Center projected inflow to Lake Powell from April to July would be 65 percent of average.

The Colorado River Compact divided the basin into an upper and lower half, with each having the right to develop and use 7.5 million acre-feet of river water annually. (Source: U.S. Bureau of Reclamation via The Water Education Foundation)

Upper Basin users, meanwhile, want to access their share of Colorado River water to meet growing demands. In Utah, a 140-mile pipeline proposal would divert as much as 86,000 acre-feet annually from Lake Powell to growing communities in the state’s southwest corner. Utah officials believe the $1 billion plan is necessary for places such as St. George that are bumping against their limits of water supply.

Furthermore, Utah officials say the state is well within its right to access water it has rights to.

“Utah’s right to develop water for the Lake Powell Pipeline is equal to, not inferior to, the rights of all the other 1922 [Colorado River] Compact signatory states,” Eric Millis, then-director of the Utah Division of Water Resources, said in a 2019 statement by the state’s Department of Natural Resources. The Colorado River Compact divided the Basin into an upper and lower half, with each having the right to develop and use 7.5 million acre-feet of river water annually.

Meanwhile, the Navajo Nation is also looking at tapping Lake Powell water via pipeline so it can supplement limited groundwater supplies.

“The continued existence of Glen Canyon Dam is imperative if the Navajo Nation is to obtain a reliable supply of water from the Colorado River,” said Stanley Pollack, an attorney for the tribe. “A water line only works if you have Lake Powell.”

In the Upper Basin, there is concern that Lake Powell has been increasingly called on to help Lake Mead, with not much to show for it.

“We are not improving the health of Lake Mead and … until and unless the Lower Basin addresses its overuse … Mead is not going to improve and it’s just going to bring the elevations of Powell down,” said Amy Haas, executive director of the Upper Colorado River Commission.

The storage/release paradigm between the two reservoirs has caused the most tension since adoption of the 2007 Interim Guidelines, said Colby Pellegrino, director of water resources for the Southern Nevada Water Authority.

The Upper Basin recognizes its obligation to let enough river flow pass to the Lower Basin, but occasional machinations with Lake Mead’s storage can be touchy. “Sometimes water is moved from Lake Mead downstream to other reservoirs or water users in a different pattern or timing, prompting concern from people in the Upper Basin that its neighbors seek to game the system,” she said.

Jeff Kightlinger, general manager, Metropolitan Water District of Southern California via Twitter.

The largest reservoir in the United States, Lake Mead receives the lion’s share of attention because of the efforts to keep it viable and supplying water to the many farms and urban areas – Las Vegas, Los Angeles and Phoenix, among them – south of Hoover Dam. In 2015, a third, deeper intake was completed at the lake to keep water flowing to Las Vegas’ 2 million residents and 40 million annual visitors. The lake supplies about 25 percent of the water needs of the Metropolitan Water District of Southern California – even more during drought.

Having a reliable Lake Powell to back up Lake Mead is crucial especially during a period of uncertainty, Lower Basin users say.

“As we get into flashier, more volatile hydrology cycles with climate change we can likely see the occasional huge storm years with less snow and more rain,” said Jeff Kightlinger, general manager of Metropolitan Water District, the largest supplier of treated water in the United States. “Having readily available storage capacity for the occasional mega year will be extremely valuable.”

‘The Most Wonderful Lake in the World’

Controversial from the start, Lake Powell remains polarizing to some degree. Former Bureau of Reclamation Commissioner Floyd Dominy, who spearheaded construction of Glen Canyon Dam that created Lake Powell in the early 1960s, said in a 2000 interview that Powell is “the most wonderful lake in the world [and] my crowning jewel.”

At capacity, Lake Powell holds more than 26 million acre-feet of water that originates as snowpack from the Upper Basin. (Source: U.S. Bureau of Reclamation via the Water Education Foundation)

Former Reclamation Commissioner Dan Beard, who served in the 1990s during the Clinton administration, opposes the continued existence of Glen Canyon Dam. Because climate change and further reductions in runoff will cause Lake Powell to keep dropping, he said, stakeholders should focus their energy on saving Lake Mead.

“Lake Mead is the heartbeat of the Colorado River,” Beard said. “It is a vital and important part of the delivery system for water to the Lower Basin states and to Mexico. It is a critical facility and yet it continues to decline.”

Beard is a board member with the advocacy group Save the Colorado, which, along with the Center for Biological Diversity and Living Rivers last year sued the federal government to force examination of climate change science in the management of Glen Canyon Dam.

The litigants say Reclamation and the Department of the Interior should conduct a revised analysis and include a full range of alternatives based on predicted climate change-related impacts on the flow of water in the Colorado River.

“Such a full range must include an alternative that incorporates the decommissioning and removal of Glen Canyon Dam because the projections from the best available climate science indicate there likely will not be sufficient flow in the Colorado River to keep Lake Powell and Glen Canyon Dam operational,” a press release accompanying the lawsuit said.

At capacity, Lake Powell holds more than 26 million acre-feet of water that originates as snowpack from the Upper Basin states of Colorado, Utah, Wyoming and New Mexico. That water gets released to Lake Mead via the Grand Canyon and helps supply the Lower Basin — Arizona, Nevada, California – as well as Mexico.

At 710 feet, Glen Canyon Dam is the second highest concrete-arch dam in the United States. (Source: U.S. Bureau of Reclamation via the Water Education Foundation)

However, since 2002 Lake Powell’s water elevation has rarely gone above its historical 50-year annual average of 3,639 feet above sea level, the point at which it contains about 15.8 million acre-feet of water. The operating system is flawed, some experts say.

Two years ago, the Colorado River Research Group, a highly respected group of Colorado River scholars including Colorado State University’s Brad Udall and University of Arizona’s Karl Flessa, produced a publication called It’s Hard to Fill a Bathtub When the Drain Is Wide Open: The Case of Lake Powell. In it, they noted that the system is stacked against Lake Powell in part because of an overallocated Colorado River system.

Lake Powell and Lake Mead operate under multiple laws and agreements that are collectively known as the Law of the River. Under the rules, Lake Powell is obligated to release a certain amount of water each year to Lake Mead for the Lower Basin states.

The Lower Basin states, however, collectively draw about 1.2 million acre-feet more water from Lake Mead than Lake Powell releases in a normal year. The result is a so-called “structural deficit.”

Amy Haas, executive director, Upper Colorado River Commission, is critical of the 2007 operating guidelines (Source: Bureau of Reclamation via the Water Education Foundation)

“The structural deficit is the true villain in this story, mixing with the operational rules to drain Lake Powell,” the Colorado River Research Group publication said. “If storage in Lake Powell cannot rebound in an era where the Upper Basin consumes less than two‐thirds of its legal apportionment, then the crisis is already real.”

Answers, the authors say, lie partly in the ability of Lake Powell storage to recover in wet years, reducing use in the Upper Basin and re-thinking exiting reservoir management. “Lakes Mead and Powell, after all, are essentially one giant reservoir and … thinking of these facilities as two distinct reservoirs, one for the benefit of the Upper Basin and one for the Lower, now seems outdated,” the publication said.

Haas, with the Upper Colorado River Commission, said the existing operating guidelines leave room for improvement. “I feel very strongly that as long as our reservoir operations are coordinated … the future of Lake Powell hinges on the future of Lake Mead,” she said. “We need to find a more equitable mechanism by which reservoir operations are coordinated.”

Marlon Duke, spokesman with the U.S. Bureau of Reclamation, the federal agency that manages the river, acknowledged that Lake Powell draws scrutiny.

“I often get asked, ‘What’s the deal with Lake Powell?’” he said. “Shouldn’t we just drain it or is it really doing what it is supposed to do?”

Jack Schmidt, with Utah State University, analyzed the concept of “Fill Mead First.” (Source: Jack Schmidt via the Water Education Foundation)

The answer, Duke said, means looking at the lake’s performance and how it has met expectations during difficult times. Powell was near capacity in 2000. Then a period of record-setting dryness set in. Through it all, enough water was released to meet the Upper Basin’s obligation to the Lower Basin.

People in the respective basins view Lake Powell and Lake Mead with a certain degree of ownership, and perspectives vary. Upper Basin interests generally want a more robust Lake Powell. South of the lake, the desire to tap into it further is not uncommon in the Lower Basin. The degree of change, ultimately, will likely fall between those sentiments.

All of that notwithstanding, it’s important to understand the two reservoirs are tightly woven, said Jack Schmidt, the Janet Quinney Lawson chair of Colorado River studies at Utah State University.

“It’s one big system and whether Powell [or Mead] goes up or down …those are intentional societal decisions of management that have little to do with climate change,” he said.

Schmidt co-authored a 2020 white paper, Managing the Colorado River for an Uncertain Future, which cautions that future flows will be “lower, more variable and more uncertain.”

Schmidt in 2016 analyzed the concept of “Fill Mead First,” the idea of establishing Lake Mead as the primary water storage facility on the mainstem river and relegating Lake Powell to a secondary storage role when Mead is full. The savings in evaporation and seepage losses would be relatively small, Schmidt said, but the idea shouldn’t be completely discounted.

Fill Mead First “generates passions and emotions,” Schmidt said. It is embraced by some as a restorative opportunity for Glen Canyon. “Then there is the world of traditional water managers who say that’s a ludicrous idea and we don’t pay any attention.”

The disparate views “live in two worlds completely.”

But Kightlinger, with Metropolitan Water District, discounts the idea of draining Powell. “Politically, I don’t see any real support or push for a fill Mead first strategy,” he said. “Powell, even less full going forward, remains a valuable piece of very expensive infrastructure that will remain part of the Colorado River storage pool for decades to come.”

Brad Udall: “…latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with
@GreatLakesPeck

A Warmer and Drier Basin

A small army of water professionals and experts constantly analyze the Colorado River Basin, which supplies water to 40 million people and fuels a huge agricultural economy.

For years, scientists have looked at the drying conditions of the Colorado River Basin, employing techniques such as tree ring sampling. Analysis of that method has shown that the years 1905 to 1922 – just as the river’s waters were being allocated among the states — were exceptionally wet.

In 2012, Reclamation’s Colorado River Basin Water Supply and Demand Study confirmed there are likely to be significant shortfalls in coming decades between projected water supplies and demands in the Colorado River Basin. Since the study, a steady stream of research points to warmer and drier conditions.

Pearce Ferry Rapid prevents predators such as catfish, bass and pike from getting upriver and destroying native fish. (Source: Cory Nielson, Arizona Game and Fish Department via the Water Education Foundation)

In April, a study published in the journal Science said the current dry period in the Southwest is one for the record books, and that its “megadrought-like trajectory” is fueled by natural variability superimposed on human-caused warming. Also in April, experts with the Western Water Assessment, whose researchers work out of the University of Colorado, Boulder and several other institutions in the region, noted that the severity and length of drought conditions can be difficult to quantify.

“This is especially true for the Colorado River system, in which total consumptive use plus other depletions typically exceeds supply, such that under even average hydrologic conditions the levels of Lake Mead and Lake Powell will tend to decline,” according to Colorado River Basin Climate and Hydrology: State of the Science, the study conducted by the Western Water Assessment.

The continued variability justifies a robust Lake Powell, said Haas, with the Upper Colorado River Commission.

“We know that future flows are going to be more variable and almost clearly lower, but we also need to ensure that our non-depletion obligation is satisfied,” she said. “Powell is our repository for this water. Doing away with the reservoir, in light of our 1922 Compact obligation, is not realistic,” she said.

Furthermore, an improved, more accurate forecasting approach is needed ahead of the next set of operating criteria. “That’s especially true given the vicissitudes of hydrology and the impacts of climate change,” Haas said.

Increasing Lake Powell’s releases is potentially problematic because of the likelihood that predator fish from Lake Mead could make it upstream and devastate native fish in the Grand Canyon.

Matt Rice, director of American Rivers’ Colorado Basin Program, believes an honest evaluation of the future of Lake Powell is needed. (Source: Matt Rice via the Water Education Foundation)

As it stands, Pearce Ferry Rapid, a rugged, impassable cataract located near the downstream end of the Grand Canyon, prevents predators such as catfish, bass and pike from getting upriver and destroying native fish. The rapid exists because Lake Mead, sitting at just 43 percent of capacity, is so low that the inflow to it from the river has carved a new entry where the river plunges over a bedrock ledge.

If Lake Mead ever began to fill again, it would inundate Pearce Ferry Rapid, allowing the non-native fish to migrate upstream and prey on native Colorado River fish. “They would just eat and eat,” said Rice, with American Rivers. “All the recovery of endangered fish could be for naught.”

Playing the Waiting Game

During a period of great uncertainty about what the next water year will bring, Colorado River water users will need to think creatively while using all their tools, including storage.

“Glen Canyon Dam exists because you need all that potential storage,” said Schmidt, with Utah State University. “In some freak years you are going to get really big runoff, and nobody wants to see that go through the system.”

Colby Pellegrino, director of water resources for the Southern Nevada Water Authority. (Source: SNWA via the Water Education Foundation)

Meanwhile, the lake’s future role in the Colorado River Basin is a key topic as Reclamation reviews the performance of the 2007 Guidelines, with results expected at the end of this year at the annual meeting of Colorado River water users.

Pellegrino with Southern Nevada Water Authority said it would be nice to get past the controversy about Lake Powell’s releases and instead find ways to store more water in it. “We have had a lot of consternation … more because of the balancing releases than the actual behavior of any water user or basin,” she said. “Going back to something that’s more constant or more fixed would remove an element of consternation between the Basins.”

What’s likely to happen is an approach that builds upon the years of collaboration and cooperation established between everyone working on Colorado River water management, said Tina Shields, water manager with the Imperial Irrigation District, the largest user of Colorado River water.

“We know how the river works – its incrementalism,” she said. “Nobody wants to make wholesale changes because it’s too big of a deal and what if it went south? We are not quick to change these relationships and negotiations. They took a lot of time.”

Chris Harris, executive director of the Colorado River Board of California, said Reclamation’s findings will be key in considering the continued conjunctive management of Lake Powell and Lake Mead.

“Certainly, the [2007] Guidelines have shown that managing the reservoirs together has kept Lake Powell from crashing and has kept Lake Mead from a shortage condition,” he said. “I believe that there will be significant interest in evaluating opportunities, including with Mexico, for even more effective management of the reservoir system.”

That process will most likely look at different elevations and trigger points for excess releases from Lake Powell in a manner that’s acceptable to the Upper and Lower Basins.

“The question is, how do you get movement either way without someone saying, ‘That doesn’t work for me,’” Shields said. “Sometimes the status quo is easier to continue than the fear associated with changing those trigger points.”

As with virtually all Colorado River issues, the ramifications of actions can run far and wide. “This sounds like an esoteric argument about something hundreds of miles away, but the reality of it is what happens at Lake Powell affects the amount of water available to the Lower Basin states, Southern California and, indirectly, Northern California,” said Beard, the former Reclamation commissioner.

California’s extensive water plumbing network relies on a careful balance of imports to Southern California from Northern California and the Colorado River.

Even with Reclamation’s review of the guidelines expected to be issued at the end of the year, Schmidt with Utah State University said he believes stakeholders will let multiple years pass before committing to any radical operational changes.

Solutions to Colorado River management are built on the legacy of collaboration and cooperation, said Tina Shields, water manager with Imperial Irrigation District. (Source: IID via the Water Education Foundation)

“Every year that we wait buys a little more information about climate change and decreasing runoff and whether we go into a wet cycle,” he said. “There’s a lot of things that could happen and people will hope that nature provides a favorable condition so there can be a tiny bit more wiggle room and we don’t go into dire crisis.”

Haas echoed the comments of many stakeholders in noting that all options for Powell’s operation should be considered. “It’s not heretical to be thinking outside the norm on things,” she said. “It spurs a more robust discussion and we should not shy away from that.”

Reclamation’s Duke harkens back to Powell’s ability to consistently meet and sometimes exceed its release obligations during severe conditions.

“That is a testament to the people who came before and had to make those tough calls,” he said. “They built that reservoir and it’s done what we needed. Looking into the future, everything’s on the table, but we also need to remember there are 40 million people who rely on water from this river and over the last 20 years, we would not have been able to supply that water reliably without these storage reservoirs.”

Reach Gary Pitzer: gpitzer@watereducation.org, Twitter: @GaryPitzer
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Expected spring #runoff into #ColoradoRiver plunges after dry April — Tucson.com

Graphic credit: Colorado River Basin Forecast Center
>

From Tucson.com (Tony Davis):

May’s monthly runoff prediction for the April-through-July period was 65% of average, or 4.6 million acre-feet. That’s 1 million acre-feet less than the April forecast predicted. Tucson Water customers typically use close to 100,000 acre-feet a year.

While low runoff this year is highly unlikely to trigger the river’s first major shortage as soon as 2021, it raises the possibility of one in 2022. A shortage would fall particularly hard on Central Arizona farmers. Flows of water into Powell that would be low enough to cause a shortage in 2022 are likely to occur about 10% of the time, said the U.S. Bureau of Reclamation’s most recent study of its reservoir operations, published in mid-April.

“This could be the start of a multi-year drought. Last year was a wet year, so one year like this we can handle,” said Eric Kuhn, a retired general manager of a northern Colorado water district and author of a recent book on the river. “One dry year doesn’t usually make a difference if we start in good shape. Two dry years or three dry years is a concern.”

The dry April weather wiped out the benefits of a robust winter snowpack in Upper Colorado River Basin states, federal forecasters said this week. Until now, this year’s forecast had been relatively stable, ranging from 74% to 82% of average runoff since January…

But Brenda Alcorn, a hydrologist for the federal Colorado Basin River Forecast Center, said that if the dry spell continues, the eventual runoff could well end up lower than what’s now predicted.

It could possibly fall as low as or lower than the 2018 runoff of 36% of normal, “if we have extreme dryness through the rest of the spring,” Alcorn said.

Since the mid-2010s, the Colorado’s spring-summer runoff has done “a lot of yo-yoing,” Alcorn said.

The runoff rose sharply in 2017, fell sharply in 2018 and soared to 145% of the average runoff in 2019.

While these fluctuations have staved off the shortages that most water experts now view as inevitable, the river is clearly more vulnerable to shortages than it was in 2000, when both Lakes Mead and Powell were full or nearly full.

Today, Lake Mead is 44% full, and Lake Powell is at 48%…

This latest bad spring-summer river runoff forecast, however, stemmed largely from dry, not hot weather, the Colorado Basin River Forecast Center said.

“April precipitation was generally below to much below average across the Colorado River Basin and Great Basin,” the center said in a report on its latest forecast. “It was exceptionally dry over northern Utah and southwest Colorado.”

A number of sites that measure snowpack in Utah and southwest Colorado showed their lowest April precipitation since officials started recording it up to 35 years ago…

April river flows neared record lows in parts of the Gunnison, Dolores and San Juan river basins in the two states.

April temperatures across the basin were generally near the average. Temperatures fell below average for the first three weeks of the month.

#Runoff news: @USBR is expecting below a normal season on the #AnimasRiver #snowpack

From The Durango Herald (Jonathan Romeo):

“I think, unfortunately, it’s one of those years that’s kind of a bummer,” said Ashley Nielson, a senior hydrologist with the Colorado River Basin Forecast Center. “Everything is going to be below average.”

Animas River Basin SNOTEL snowpack graph May 3, 2020 via the NRCS.

Snowpack in the San Juan Mountains this winter hovered near historic averages, according to Snotel sites, which track snow depth.

But Snotel sites tell only part of the story.

For one, there are a limited number of sites in the basin. And this year, elevations above most Snotel sites around 11,000 feet didn’t receive as much snow as usual.

To make matters worse, drought conditions last summer and fall caused the ground to dry up significantly, so soil likely will absorb more snowmelt than normal, at the expense of rivers and streams.

As a result, the Colorado River Basin Forecast Center predicts the Animas River will receive about 70% of the water it usually does in spring, Nielson said.

The forecast center also predicts the Animas River likely will hit a peak flow of 2,300 to 2,500 cubic feet per second, though as much as 3,000 cfs is possible…

As of Friday, Snotel records show Southwest Colorado’s snowpack is melting at an accelerated rate: Snowpack in the San Juans is 70% of normal historic averages for this time of year.

Jarrod Biggs, assistant utilities director for the city of Durango, said a heavy snowpack year in the winter of 2018-19 provided good storage for the town’s reservoir, which should help water reserves during a below-normal runoff.

The city of Durango gets most of its water from the Florida River and supplements supply from the Animas River when demand increases…

Water is not being pulled from the Animas River to Lake Nighthorse this year, said Russ Means, general manager of the reservoir, as crews work on the intake structure across from Santa Rita Park.

On Friday, the Animas River was running at 1,700 cfs, which is 25% higher than average for this time of year, said Frank Kugel, director of the Southwestern Water Conservation District.

San Juan River Basin. Graphic credit Wikipedia.

@USBR: Water experiment to be conducted along the #ColoradoRiver while maintaining hydropower production this summer #COriver #GrandCanyon

Non-biting midges are one of the aquatic insects predicted to benefit from the Bug Flow Experiment. Photo credit: USGS/Freshwaters Illustrated via the Bureau of Reclamation.

Here’s the release from the Bureau of Reclamation (Marlon Duke, Robyn Gerstenslage):

From May 1 through August 31, the Department of the Interior will conduct a Macroinvertebrate Production Flow at Glen Canyon Dam. This experiment, also known as a Bug Flow, aims to improve egg-laying conditions for aquatic insects, which are the primary food source for endangered and native fish in the Colorado River. This is the third consecutive year for the Bug Flow under the Glen Canyon Dam Long-Term Experimental and Management Plan.

During the Bug Flow experiment, the Bureau of Reclamation will make targeted adjustments to water releases from Glen Canyon Dam and Lake Powell. That adjusted release schedule will include low and steady flows during weekends, while weekday operations will maintain normal flows to meet hydropower demands. Weekday release rate hourly changes will remain unchanged.

Aquatic insects lay and cement their eggs to rocks, vegetation and other materials near the river’s edge. If flows are too variable, water levels may drop below where eggs are laid, causing them to dry out and die.

Caddis fly hatch photo via http://ValiValleyAnglers.com

“Findings indicate that some aquatic insects are already benefiting from the bug flows, which also benefits fish and other animals that eat them,” said Scott VanderKooi, chief of the U.S. Geological Survey’s Grand Canyon Monitoring and Research Center. “For example, our research suggests that caddisflies, an extremely rare aquatic insect in the Grand Canyon over the past several decades, increased nearly four-fold during the first year of the experiment in 2018, before returning to pre-Bug Flows numbers in 2019. In contrast, non-biting midges, another type of aquatic insect that is a key food source for fish and other wildlife, may have increased, and a third year of Bug Flows should help verify this finding.”

Colorado River from Lee’s Ferry. Photo credit. Gonzo fan2007 – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=3631180

Recreational fishing at Lees Ferry also improved during Bug Flows, with anglers catching an average of 1-2 more rainbow trout per day during Bug Flow weekends, when flows were low and steady, compared to weekdays when flows fluctuated.
“Our current experimental plan initially recommended two to three years of Bug Flows given the complexity of the Colorado River ecosystem, which is constantly changing,” said Lee Traynham, Reclamation’s Glen Canyon Dam Adaptive Management Program Manager. “We’ve already learned a lot about the ecosystem and have observed several resource improvements over many years of experimenting with flows. We are excited to see how the ecosystem responds this year.”

The decision to conduct this experiment was based on technical input and recommendation from a collaborative team of scientists and technical experts from federal agencies and states involved in the Glen Canyon Dam Adaptive Management Program. This team includes representatives from the Department of the Interior’s Bureau of Reclamation, National Park Service, U.S. Geological Survey, U.S. Fish and Wildlife Service, and Bureau of Indian Affairs; the Department of Energy’s Western Area Power Administration; Arizona Game and Fish Department, Upper Colorado River Commission and all seven Colorado River Basin States.

Experiments are designed to maximize benefits to the Colorado River ecosystem through the Grand Canyon, while meeting water delivery requirements and minimizing negative impacts to hydropower production.

This experiment is expected to benefit aquatic insects and the fish, birds and bats that feed on them, while providing valuable scientific information for future decision making.

For more information about the Glen Canyon Dam Adaptive Management Program and flow volumes below Glen Canyon Dam, please visit the following websites:

Glen Canyon Dam Adaptive Management Program: https://www.usbr.gov/uc/progact/amp/index.html

Flow volumes for the Colorado River at Lees Ferry: https://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09380000

Colorado River Storage Project: https://www.usbr.gov/uc/rm/crsp/index.html

Citizen Science Light Trapping in Grand Canyon: https://www.usgs.gov/centers/sbsc/science/citizen-science-light-trapping-grand-canyon?qt-science_center_objects=0#qt-science_center_objects

Science Behind the Bug Flows: https://pubs.er.usgs.gov/publication/70170803

Project Management Plan Developed for Arkansas Valley Conduit — Southeastern Colorado Water Conservancy District

Arkansas Valley Conduit “A Path Forward” November 22, 2019 via Southeastern.

Here’s the release from the Southeastern Colorado Water Conservancy District (Chris Woodka):

Southeastern Colorado Water Conservancy District and the Bureau of Reclamation have adopted a project management plan that will guide construction of the Arkansas Valley Conduit (AVC).

The AVC is a pipeline project that will deliver clean drinking water to 40 communities serving 50,000 people from Pueblo Dam to Lamar and Eads on the eastern plains. This water supply is needed to supplement or replace existing poor quality water and to help meet AVC participants’ projected water demands. The estimated cost of the AVC is between $564 million and $610 million.

“The Project Management Plan is the blueprint for how we will build the Arkansas Valley Conduit, and an important step in the future of the AVC,” said Bill Long, President of the Southeastern District Board of Directors. “The AVC is absolutely necessary for the future water quality and health of the Arkansas Valley.”

“The Department of the Interior and Reclamation are committed to improving the water supplies of rural southeastern Colorado,” said Commissioner Brenda Burman. “I look forward to our continued collaboration with Southeastern to move this long-delayed project forward.”

“The communities of the Lower Arkansas Valley deserve clean drinking water, which the Arkansas Valley Conduit will supply for 50,000 Coloradans for generations to come,” said Senator Cory Gardner, R-Colo. “I was proud to secure robust federal funding of $28 million to begin construction for the first time since Congress authorized the project and President Kennedy promised completion nearly six decades ago. The project management plan adopted by the Bureau of Reclamation and the Southeastern Colorado Water Conservancy is another great step forward for this project and I’ll continue to work with local and federal leaders to ensure we deliver abundant and affordable clean drinking water to the Colorado communities in need.”

“This is a significant milestone in our efforts towards construction of the AVC,” said Jeff Rieker, Eastern Colorado Area Manager for Reclamation. “This plan will guide design and construction by Reclamation and Southeastern, and streamline our joint efforts to provide clean water to these communities.”

Reclamation and Southeastern have worked together for the past year to envision a layout for the AVC that reaches communities with the poorest water quality most quickly, reduces overall costs, and reduces the need for federal appropriations. Many communities have issues with radioactive elements in groundwater supplies. Others face increasing costs to treat water and to dispose of waste by-products from that treatment.

Under the plan, AVC water will be delivered to a point east of Pueblo by the Pueblo Board of Water Works. A contract among Reclamation, Pueblo Water and Southeastern is in the discussion stage.

From that point, Reclamation will construct the trunk line, a treatment plant and water tanks, while Southeastern will coordinate with communities to fund and build connections. Reclamation and Southeastern continue to meet regularly, using remote technology, to work on activities such as design, land acquisition and environmental review that will lead to construction.

“We’re on a path to begin construction in the near future, but we still have a lot of work to do,” said Kevin Karney, who chairs Southeastern’s AVC Committee. “Part of that will be reaching out to AVC participants to help shape how the AVC is developed. Overall, I’m excited to see the AVC moving forward.”

Congress provided additional funds to Reclamation in FY 2020. Reclamation allocated $28 million for construction of the AVC in February, and an additional $8 million for 2021 was requested in the President’s budget. The Colorado Water Conservation Board approved a $100 million finance package that still must be approved by the Colorado Legislature. Other potential sources of funding are being considered.

The AVC was part of the 1962 Fryingpan-Arkansas Project Act, but was never built because communities could not afford 100 percent of the costs. In 2009, the Act was amended to provide a 65 percent federal cost share. Reclamation identified a preferred alternative in 2014, which has been modified in the latest project management plan.

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For additional information, contact Chris Woodka at Southeastern, (719) 289-0785; Darryl Asher at Reclamation, (406) 247-7608.

Fryingpan-Arkansas Project via the Southeastern Colorado Water Conservancy District