New Reservoirs, Dams Planned for Colorado Front Range — Engineering News Record

From the Engineering News Record (Thomas F. Armistead):

“In the water-scarce West, there is little to no new water,” says Laura Belanger, water resources and environmental engineer with Western Resource Advocates. “What we’re seeing is a shift to a suite of solutions that make the most of our region’s water resources. So the first line is and always should be conservation, because that’s the most cost-effective thing utilities can do, and it’s also fast.”

[…]

In Colorado’s Front Range, the Northern Colorado Water Conservancy District is accepting qualification statements for construction of Colorado’s tallest new dam in a half-century, with selection of a contractor and notice to proceed by December, says Joe Donnelly, spokesman. The main dam will be a rockfill structure with a hydraulic asphalt core, 360 ft tall and 3,500 ft long at the crest. The dam will impound the 90,000 acre-ft Chimney Hollow Reservoir for the Windy Gap Firming Project. A contract for design was awarded to Stantec in 2016.

The reservoir would store water for 12 municipalities and other water suppliers. The project has support from both public authorities and some environmental advocates. But six environmental groups are contesting the project in federal court because it will divert 30,000 acre-ft annually from the Colorado River, taxing the already challenged flow of that body.

Denver Water is proceeding with the expansion of Gross Reservoir, built in the 1950s with a 1,050-ft-long, 340-ft-tall concrete gravity arch dam impounding 42,000 acre-ft of water. Following 14 years of planning, the U.S. Army Corps of Engineers issued a 404 permit in July 2017, allowing Denver Water to raise the reservoir’s dam 131 ft and expand the reservoir’s capacity to 77,000 acre-ft.

The utility is expanding the reservoir to address a known imbalance in the city’s water system, said Jeff Martin, program manager for the project, in a video on the project’s website. The North System, where Gross Reservoir is located, stores about 30% of the water, and the South System the rest. The imbalance results from differential snowpack runoff on the system’s north and south sides. “This will provide extra insurance and extra reservoir capacity to make sure that we can weather those times when we do have issues in our system,” Martin said…

Some existing storage facilities are being expanded or are having their water reallocated, and regional water sharing also is beginning to grow, Belanger says. She cites the Chatfield Reservoir, built in 1965 on the South Platte River south of Denver for flood control, as an example. The U.S. Army Corps of Engineers determined that up to 20,600 acre-ft of the water can be reallocated to drinking water and industrial supply, agriculture, environmental restoration and other purposes without compromising its flood-control function. Environmental mitigation and modifications are expected to cost about $134 million.

Down on the Ground in the Anthropocene City-State — Colorado Central Magazine

George Sibley

Full disclosure, I have written articles for the magazine in the past.

Here’s a look at Denver Water’s Moffat Collection System Project and the Boulder County Commissioner’s hearing on 1041 jurisdiction from George Sibley that’s running in Colorado Central Magazine. Click through and read the whole article. Here’s an excerpt:

An interesting thing happened mid-March in Boulder which the media seem to have mostly missed. Commissioners from Grand County showed up at a noisy Boulder County commissioners’ hearing on a West Slope-to-East Slope transmountain water diversion project – to testify on behalf of the project. It is probably the first time ever, in the generally contentious history of Colorado water development, that the people in a basin of origin have supported a transmountain diversion project that people in the basin of destination oppose.

Although this is a story from just beyond our Central Colorado boundaries, it is a story of interest to anyone in the West who is wondering how, or even if, we are going to finally leave the 20th century and venture into the 21st and the Anthropocene Epoch we keep trying to pretend we haven’t brought on ourselves.

The report on the Boulder County hearing sounded like your usual 20th century public hearing on the kind of issue that seems almost structured to pit environmentalists against the developers of something or other – a hearing in which no one has to listen because everyone already knows what everyone else is going to say.

The issue in this case pits the usual Front Range environmental organizations against a public utility that everyone loved to hate through the 20th century, Denver Water (DW). DW wants to enlarge the Gross Dam and Reservoir it built in the 1950s in the foothills near Boulder, to hold some additional water it wants to import from the West Slope – its “Moffat Firming Project” which would bring a third more water on average through its Moffat Tunnel Project from the Fraser and Williams Fork Rivers in the Upper Colorado River watersheds…

For the West Slope and Grand County, DW is both funding and actively participating in planning and executing a Learning by Doing process – essentially, an adaptive management process of active experimentation in learning how to live with less water. Some of it is more conventional work providing funding and expertise to water treatment districts and irrigation districts needing to use less water more efficiently.

But some of it will actually be what strikes me as “creative environmentalism”: Actually reconstructing some streams to function ecologically with a permanent reduction of water – call it “downsizing” the stream to fit the unignorable realities of the future. Channels are narrowed and deepened to cool the waters, helping both the aquatic ecosystem and the human economy of floaters and fishermen; riparian vegetation is planted to shade the stream and stabilize banks; meanders are induced to give a healthy stability and resilience for the foreseeable diminished future. Half a mile of the Fraser near U.S. 40 has been so ‘remodeled’ and is open to public inspection (and fishing). DW has committed millions to this work. (The CRCA can be found online by browsing for the name in full.)

@BoulderCounty commissioners affirm right to review Gross Reservoir expansion plans

Gross Dam enlargement concept graphic via Denver Water

From The Boulder Daily Camera (Charlie Brennan):

After more than four hours of impassioned pleas from members of the public Thursday night, Boulder County commissioners voted unanimously that Denver Water’s planned expansion of Gross Reservoir must go through the county’s review process.

That vote, affirming an earlier finding by Boulder County Land Use Director Dale Case, now poses a significant challenge for the utility, which serves 1.4 million water users in the Denver metro area — none of them in Boulder County — and claims the project is needed to meet the needs of metro population that’s just going to keep growing.

“I think it’s just critical that local people have their say on this project that affects them the most,” said Boulder County Commissioner Matt Jones, just before the vote was taken…

Denver Water’s plan had been to start construction this year on a project to raise the Gross Reservoir Dam in southwestern Boulder County by 131 feet to a height of 471 feet and to expand the reservoir’s capacity by 77,000 acre-feet.

The cost of the endeavor, said to be the biggest construction project ever contemplated in Boulder County, is now estimated at $464 million (in 2025 dollars) and could take at least six years to complete.

Boulder County Land Use Director Dale Case issued a finding on Oct. 22 that Denver Water’s plans, formally known as the Moffat Collection System Project,were subject to the county’s so-called “1041” review process — that number references the state House bill passed in 1974 allowing local governments to regulate matters of statewide interest through a local permitting process.

Denver Water however, has argued to the contrary.

“We contend that state law exempts the expansion from the 1041 process because it was permitted under local land use codes at the time that the state enacted the law authorizing the 1041 review process,” said Denver Water spokesman Travis Thompson.

Pair of lawsuits challenges need for more #ColoradoRiver water — @AspenJournalism #COriver

The spillway and dam at the Windy Gap Reservoir on the headwaters of the Colorado River. Photo: Brent Gardner-Smith/Aspen Journalism

From Aspen Journalism (Lindsay Fendt):

Two lawsuits making their way through the federal court system are challenging two significant water projects in Colorado designed to divert more water from the Colorado, Fraser and Williams Fork river basins in Grand County.

The projects — Northern Colorado Water Conservancy District’s Windy Gap Firming project and Denver Water’s Moffat Collection System Project — would provide a combined firm yield of 48,000 acre-feet of water for the sprawling Front Range.

But environmental groups say government agencies violated the law in the environmental permitting processes of both projects.

“Our biggest claim is that [the agencies] claim they looked at reasonable alternatives [to the projects],” said Gary Wockner, the director of Save the Colorado, the lead plaintiff on both cases. “But they didn’t look at conservation or efficiency. Water providers are trying to go to big water projects first and not the cheaper option of conservation.”

Both Northern and Denver Water say they factored in conservation efforts when they calculated water demand and that even aggressive conservation efforts won´t be enough to meet water demand in the future.

“There are only a few answers for water supply in the future and Windy Gap Firming is one of those options,” said Brad Wind, the general manager of Northern Water. “Without that project, I can’t fathom where we will end up.”

But some water experts say that the state’s use of population growth as one of the major drivers of water demand was flawed.

“As population goes up, water demand continues to go down and it’s been that way for decades,” said Mark Squillace, a water law expert at the University of Colorado Law School.

Denver Water’s collection system via the USACE EIS

Decoupled demand

The phenomenon of increasing populations with declining water use is known as “decoupling,” and it has been happening in nearly every part of Colorado since the 1990s.

Higher efficiency appliances, utility-driven conservation programs and greater citizen awareness of water shortages have all driven the change.

But water managers say the state’s growing urban areas are reaching the point of “demand hardening,” where the additional water that can be conserved will not outweigh the amount needed in the future.

“We have been hearing those kind of stories for a long time and it never happens,” Squillace said. “There are a lot of things that we could still do on the conservation end that would be a lot cheaper [than new infrastructure] and a lot more consistent with the environment that we live in.”

While they differ, the pair of lawsuits being spearheaded by Save the Colorado could both hinge on demand and conservation estimates, and the assumption that additional conservation won’t be sufficient in the future.

Both lawsuits were filed in federal district court and are now awaiting action by a judge to move forward.

The Windy Gap Firming case was filed in October of 2017 against the U.S. Bureau of Reclamation and the U.S. Army Corps of Engineers.

The Moffat Collection System case was filed in December against the Army Corps, the U.S. Interior Department and the U.S. Fish and Wildlife Service.

An aerial view of Windy Gap Reservoir, near Granby. The reservoir is on the main stem of the Colorado River, below where the Fraser River flows into the Colorado. Water from Windy Gap is pumped up to Lake Granby and Grand Lake, and then sent to the northern Front Range through the Adams Tunnel.

The projects

Both the Windy Gap and Moffat projects were conceived decades ago to address projected water shortages on Colorado’s Front Range and to add resilience to both Northern and Denver Water’s supplies.

Now estimated to cost about $600 million, the Windy Gap project will include a new 90,000 acre-foot reservoir in western Larimer county called Chimney Hollow Reservoir.

The reservoir is designed to store water from the Colorado and Fraser rivers transported from the Western Slope through the existing infrastructure of the Colorado-Big Thompson project.

Windy Gap Reservoir, built in 1985, is created by a low river-wide dam across the main stem of the Colorado River, just downstream from where the Fraser River flows in.

The reservoir is relatively small, holding 445-acre feet, but it’s well situated to gather water from the Fraser, pump it up to Lake Granby and Grand Lake, and then send it through the Adams Tunnel under the Continental Divide.

With the Moffat project, Denver Water plans to spend an estimated $464 million in order to expand Gross Reservoir in Boulder County, by raising the height of the dam by 131 feet, in order to store an additional 77,000 acre-feet of water.

Gross Reservoir is a part of the utility’s existing northern collection system and is filled with water from the headwaters of the Fraser and Williams Fork river basins. The water is moved through a pipeline in the Moffat Tunnel, which runs east through the mountains from the base of the Winter Park ski area.

The upper South Platte River, above the confluence with the North Fork of the South Platte. Photo: Brent Gardner-Smith/Aspen Journalism

The fork not taken

The plans to expand Gross Reservoir started in 1990 after the EPA rejected Denver Water’s plan to build Two Forks Reservoir on the South Platte River.

The EPA’s rejection of Two Forks signaled the end of an era of large dams and forced groups planning large water infrastructure projects to give more consideration to the environmental impacts of their plans.

Following this rebuke, Denver Water turned to the environmental groups that had opposed their project and solicited advice.

Throughout the 1990s, the utility implemented water conservation and recycling programs and started making plans to expand an existing reservoir instead of building a new dam.

“We embarked on the path that the environmental groups suggested. We implemented a conservation program and reduced our demands,” said Jim Lochhead, the CEO and manager of Denver Water. “But you can’t get to zero. We continue to be committed to conservation, but at the end of the day we still need more water.”

In partnership with environmental groups like Western Resource Advocates and Trout Unlimited, Denver Water has agreed to spend $20 million on environmental improvements in watersheds on the Western Slope as part of the Gross Reservoir expansion.

Denver Water has also agreed to a monitoring program that will require them to mitigate any unforeseen environmental problems caused by the project, a compromise between environmental groups and the largest water utility in the state.

“In some sense this project was the development of an alternative from a number of groups,” said Bart Miller, the director of the Healthy Rivers Program at Western Resource Advocates. “In some respect you are putting this in context next to what could happen or could have happened.”

Concerned with having their own projects fail, as Two Forks did, other water managers emulated Denver Water’s strategy.

When Northern Water started planning for the Windy Gap Firming project it also reached out to environmental groups, and ended up committing $23 million to mitigate problems caused by past projects and to make other improvements in the upper Colorado River watershed.

Even though there will be impacts from taking more water from the river, Northern Water says that these “environmental enhancements” will leave the river better off than it would be without the project.

And environmental groups working on the project agree.

“There is a lot of damage on the river that will continue to go on without an intervention,” said Mely Whiting, legal counsel for Trout Unlimited. “This is probably the best shot.”

Gross Reservoir in the mountains to the southwest of Boulder. Denver Water hopes to increase the height of the dam 131 feet, to a new height of 471 feet, to store three times as much water, which it says will help it meet increasing demands and to better weather severe droughts.

The lawsuits

While some environmental groups have seen compromise as the best step forward, Save the Colorado and the other plaintiffs in the two lawsuits take a harder stance.

Save the Colorado, in particular, is against any new dams or diversions.

“The river has already been drained enough,” Wockner said. “The mitigation, in our mind, is not consequential.”

Colorado and the six other states that use Colorado River water are now negotiating a plan to better manage Lake Powell and Lake Mead in response to drought and acidification.

Last week, an engineer from Northern Water told the city council of Loveland that it may have to take a ten percent cut in the water it draws from the headwaters of the Colorado River, sending the water instead to Lake Powell, where water is held before being moved through the Grand Canyon and into Lake Mead for use in California, Arizona and Nevada.

And Northern’s statement did not go unnoticed by the plaintiffs in the Windy Gap and Moffat lawsuits.

“The old guard in water have the default setting that we need to build more reservoirs and we need to find more ways to bring water from the western slope,” said Kevin Lynch, the lawyer representing the environmental groups in the Windy Gap Firming case. “The argument my clients are hoping to make with this case is that that may have made sense in the past but it doesn’t now. We are definitely trying to buck the status quo and change the historical way of doing things.”

Lynch and his team are arguing that the Bureau of Reclamation and the Army Corp of Engineers — the two government agencies being sued in the Windy Gap Firming case — failed to update and independently verify the water demand data used to justify the project.

To back up this allegation, the plaintiffs petitioned the court to include a statistics report in the administrative record.

The report, which looks at water use statistics in communities with stakes in Windy Gap Firming water, showed that their demand projections made back when the agencies conducted their environmental assessments were between 9 and 97 percent higher than the actual water use rates in those areas.

The lawyers in the Moffat Project lawsuit also found that Denver Water used old data from 2002 to project their demands future demands.

The complaint filed by the plaintiffs says that the Army Corps and the Department of the Interior — which are the two agencies being sued in the Moffat case along with the Fish and Wildlife Service — ignored more recent data that was available when they conducted their assessments.

“If they were to use today’s data they would no way be able to justify that they need the water,” said Bill Eubanks, the lawyer for the plaintiffs in the Moffat Project case. “Here we are talking about almost two decades. Two decades where we have seen the most transformative uses of water in a century.”

Both legal teams say that even if the data did reveal a demand for more water, the agencies failed to analyze the alternatives to two large infrastructure projects, including conservation.

Specifically, Wockner and Eubanks both spoke about how a “cash for grass” program — where the government pays people to dry up their lawns — was never analyzed as an alternative. Looking at similar programs in California, they say the same amount of water could be saved, but for less money than either of the two infrastructure projects.

To this claim both Northern Water and Denver Water say that additional conservation measures are already planned for the future, but that they are not enough.

“The state has done a lot of studies for need for water on the Front Range,” said Jeff Drager, Northern Water’s director of engineering and the project manager for the WIndy Gap firming project. “We agree that there can be more conservation, but it won’t be enough to meet our participants needs.”

The pipeline, at the base of the Winter Park ski area, that moves water as part of the existing Moffat Collection System Project. The portal of the railroad tunnel is behind the pipeline, in this view. Photo credit: Brent Gardner-Smith/Aspen Journalism

Looking forward

Due to a long backlog in the court, both lawsuits are unlikely to see their day in court any time soon. According to both lawyers, it could be months or years until the cases are decided. The court’s slow pace could impact the construction of both projects.

Citing the lawsuit, Northern Water delayed bonds to build the project back in August.

Executives at Northern say they are using the time to hammer out the last of the details of the project’s design, but that if the project is delayed it may cause costs to rise or endanger the water supplies of the project’s participants.

Denver Water is still waiting on several permits before they can begin planning construction and is less concerned about a delay. Both Lochhead and Wind say they believe that the projects will go forward once the lawsuits are resolved.

“We feel confident that our permitting processes are on solid ground,” Wind said. “I don’t think there is anyone in this organization at all that has thought this lawsuit would be effective.”

While both Northern Water and Denver Water are confident that their projects will move forward, the plaintiffs in the cases are hoping for an upset that could topple the entire water system in Colorado.

“If we win this case, using this particularly egregious example of inaccurate water demand projections, we think we can set a precedent that would force the state to look at more recent data for different types of projects,” Eubanks said.

Boulder County commissioners set March 14 public hearing on Gross Reservoir expansion appeal

The dam that forms Gross Reservoir, located in the mountains west of Boulder. Photo: Brent Gardner-Smith/Aspen Journalism

From The Boulder Daily Camera (Amy Bounds):

Community members wanting to comment next month at a Boulder County commissioners hearing on whether Denver Water can move forward with an expansion of Gross Reservoir can start signing up next week…

Online sign-ups for the March 14 hearing start Feb. 14, while in-person sign-ups will start an hour before the hearing.

Commissioners plan to continue to take public testimony until all speakers have had an opportunity to comment, according to a news release.

After the public hearing, commissioners will hear Denver Water’s appeal of a decision by the county’s Land Use Department that Denver Water must run the project through what is known as a “1041” review process before construction can begin.

Named for the bill number by which it was enacted in 1974, the 1041 legislation gives local governments the right to control development by agencies beyond their boundaries through a local permitting process.

Denver Water argues the Gross Reservoir expansion is exempt from 1041 requirements. Boulder County claims it is not.

The public hearing will focus on the limited scope of the determination and is not a hearing or decision on the perceived impacts or merits of the reservoir expansion project, according to a news release…

Written comments can be submitted through an online comment form available at bit.ly/GrossDamExpansion. Comments also can be mailed to the Boulder County Commissioners’ Office, P.O. Box 471, Boulder, 80306. Comments need to be received by noon March 12.

Moffat Collection System Project update: “I think their position is pretty clear” — Jim Lochhead #ColoradoRiver #COriver #aridification

Denver Water is seeking approvals from the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, and the state of Colorado to expand Gross Reservoir, which is southwest of Boulder. The 77,000 acre-foot expansion would help forestall shortages in Denver Water’s water system and offer flood and drought protection, according to Denver Water.

From The Sky-Hi News (Lance Maggart):

On Wednesday a collection of six environmental advocacy groups – Save the Colorado, the Environmental Group, Wildearth Guardians, Living Rivers, Waterkeeper Alliance Inc. and the Sierra Club – filed a lawsuit in Colorado’s federal district court against the proposed Gross Reservoir Expansion Project, alternately called the Moffat Firming Project…

The legal process surrounding Gross Reservoir has deep significance to Grand County. The county serves as the source for much of the water Denver Water relies upon, which is transported out of the county through the Moffat Tunnel near Winter Park Resort. The county is also party to a collaborative water management group called Learning By Doing. The group looks to improve river habitat in Grand County by conducting environmental water projects and through other means.

The lawsuit filed by the environmental groups does not name Denver Water and instead is directed at the US Army Corps of Engineers, the Department of the Interior and the US Fish and Wildlife Service. The 57-page complaint lays out 32 separate specific claims related to alleged violations of the National Environmental Policy Act, the Clean Water Act and the Endangered Species Act.

The alleged violations claimed by the environmental groups cover a wide range of technical issues related to the formal processes by which large construction projects, such as the Gross Reservoir Expansions, are approved by federal agencies. Many of the claims made by the environmental groups revolve around allegations that the Corps of Engineers, Interior Dept. and US Fish and Wildlife failed to exercise independent judgment related to claims made by Denver Water about the project.

“Denver Water’s proposal to build the largest dam in Colorado history will hurt the 40 million people in six states and two countries who depend on the Colorado River – a critical but disappearing, resource – for their water supply,” said Daniel E. Estrin, general counsel and advocacy director at Waterkeeper Alliance. “Waterkeeper Alliance stands united with our many Colorado River Basin Waterkeepers who are fighting to protect their waterways and their communities from this senseless and destructive water grab.”

For their part officials from Denver Water said the court filing did not surprise them.

“We expected it,” Jim Lochhead, CEO of Denver Water, said. “This is a really critical project for Denver Water. In the last 15 years we have come close to running out of water a couple of time at the north end of the system.”

Lochhead noted that those two incidents came in 2002 and 2013.

While Denver Water is not directly named in the lawsuit Lochhead said the organization will be entering the lawsuit to “provide our own perspective on the adequacy of the approvals.”

“We are confident the federal agencies follow regulations and federal law,” Lochhead said. “I think a court will uphold the findings by those agencies.”

When asked whether he believed Denver Water and the environmental groups who oppose the Gross Reservoir Expansion Project could reach some form of compromise agreement Lochhead answered, saying, “I think their position is pretty clear.”

Moffat Collection System Project update: Environmental groups file lawsuit

The dam that forms Gross Reservoir. Photo: Brent Gardner-Smith/Aspen Journalism

From Colorado Public Radio (Grace Hood):

A suit filed against three U.S. government agencies seeks to stop the expansion of Denver Water’s Gross Reservoir in Boulder County…

Gross Reservoir provides water to 1.4 million Front Range customers. The expansion would divert more water from Colorado River headwater tributaries during wet years. In a nutshell, the project seeks to raise the height of the existing dam by 131 feet; storage capacity would increase by 77,000 acre feet.

The environmental groups who sued say the U.S. government permitting process inadequately evaluated the impact of the large project on streamflows. There are also concerns about how construction would affect wildlife.

“We went above and beyond mitigation of environmental impacts under the permits,” Denver Water CEO Jim Lochhead said. “We sat down with Grand County, Eagle County… and a host of agencies across Western Colorado, and developed a series of environmental enhancements to the streams of Western Colorado.”

Trout Unlimited is one such group that has supported the Gross Reservoir expansion, citing successful stream augmentation programs along the Fraser River…

Revving up the legal gears could pose a setback for Denver Water, which has spent years securing the necessary permits. Now that it has those in place, environmental groups are seeking to stop construction.

Denver Water’s collection system via the USACE EIS