Booming Front Range cities take first steps to build $500 million dam, reservoir near Holy Cross Wilderness — The Denver Post

Here’s an in-depth report from (Bruce Finley) writing in The Denver Post. Click through and read the whole article. Here’s an excerpt:

A hundred miles from Colorado’s Front Range house-building boom, field scientist Delia Malone dug her fingers into spongy high-mountain wetlands at the edge of the Holy Cross Wilderness.

She found, about 15 inches underground, partially decayed roots, twigs and the cold moisture of a fen. These structures form over thousands of years and store water that seeps down from melting snow.

Malone has been digging about 20 holes a day, surveying fens for the U.S. Forest Service, to better understand nature’s water-storage systems — which sustain vegetation and stream flows that 40 million people across the Colorado River Basin rely on in the face of increasing aridity.

Aurora and Colorado Springs are planning to flood these wetland fens and replace natural storage with a man-made system: a $500 million dam and a reservoir that may require changing wilderness boundaries.

The cities each own rights to 10,000 acre-feet a year of the water that flows out of the wilderness and would pump what the reservoir traps, minus evaporation, through tunnels under mountains to other reservoirs and, finally, to pipes that deliver steady flows from urban faucets, toilets, showers and sprinkler systems…

Fens play a key role ensuring that streams and rivers still flow after winter snow melts. And as climate warming leads to earlier melting and depletes surface water in the Colorado River, natural wetlands increasingly are seen as essential to help life hang on. The benefits stood out this summer as the West endured record heat, wildfires and drought…

Yet Front Range developers’ desire for more water is intensifying. Across the mountains at construction sites on high dusty plains, roads and power lines have been installed, heavy dirt-movers beep and carpenters thwack atop roofs.

Local governments already have approved permits allowing house-building at a pace that in some areas is projected to nearly double water consumption.

Colorado Springs officials issued 3,982 permits for new single family homes last year, 18% higher than the average over the previous five years, according to data provided to The Denver Post. They estimated the current population around 476,000 will reach 723,000 “at build-out” around 2070. This requires 136,000 to 159,000 acre-feet of water a year, city projections show, up from 70,766 acre-feet in 2019.

Aurora officials estimated their population of 380,000 will reach 573,986 by 2050. They’ve approved entire new communities, such as the 620-acre Painted Prairie with more than 3,100 housing units in the “aerotropolis” that Denver leaders have promoted near Denver International Airport, and projected current water consumption of 49,811 acre-feet a year will increase to 85,000 acre-feet and even as much as 130,158 acre-feet in a high-growth, rapid-warming scenario…

To make a new dam and reservoir more palatable, the cities are exploring unprecedented “mitigation” of digging up and physically removing the underground fens, then hauling them and transplanting them elsewhere to restore damaged wetlands. An experiment on a ranch south of Leadville, officials said, is proving that this could help offset losses of Homestake Creek wetlands.

This would challenge a federal policy laid out in 1999 at Interior Department regional headquarters in Denver that classifies fens as “irreplaceable.” The policy says “onsite or in-kind replacement of peat wetlands is not thought possible” and that “concentrated efforts will be made to encourage relocation of proposed reservoirs… that might impact fens, when practicable.”

Covered by grasses and shrubs, water-laden fens blanket the Homestake Valley — wetlands filled with porous peat soils that receive minerals and nutrients in groundwater. Moving such wetlands, if attempted, would require massive hauling of soil blocks combined with the delicate precision of an organ transplant to retain ecological functioning…

Some environmental groups are preparing for legal combat should the cities seek required state, county and federal permits. Others haven’t weighed in. Conservation Colorado leaders declined to comment on this water push.

Transplanting fens as mitigation to try to restore wetlands elsewhere “for our convenience” is impossible, WildEarth Guardians attorney Jen Pelz said. “Fens and other sensitive high-elevation wetlands are quite beautiful and mysterious, more art than science, not something we can re-engineer.”

Dams and diversions proposed in recent years around the West “are just as destructive as those built a century ago, and building dams today is actually more irresponsible because we know that dams disconnect aquatic and riparian habitat, cause species extinction, disrupt ecosystem function, dry rivers and harm native cultures and communities,” she said.

“We need to start removing dams, not building more. This project is one of many where water managers are looking to cash in on their undeveloped rights or entitlements at the expense of people and the environment. … It’s time to draw a line in the sand.”

USFS solicits comments on proposed #Aurora dam near Holy Cross — The Aurora Sentinel

A wetland area along Homestake Creek in an area that would be flooded by a potential Whitney Reservoir. The cities of Aurora and Colorado Springs are looking to develop additional water in Eagle County and divert it to the Front Range. Photo credit: Brent Gardner-Smith/Aspen Journalism

From The Aurora Sentinel (Grand Stringer):

The White River National Forest opened a public comment period last week concerning the next phase of a would-be reservoir project dubbed the Whitney Reservoir. Water authorities in Colorado Springs and Aurora plan to divert water near the Vail Valley — normally destined for the Colorado River — to the Front Range by way of pumps and tunnels.

Greg Baker, Aurora Water’s manager of public relations, said in November the Whitney Reservoir could eventually hold between 9,000 acre-feet and 19,000 acre-feet of water.

For comparison, Cherry Creek Reservoir stores more than 134,000 acre-feet.

Aurora Water and its southern counterpart, Colorado Springs Utilities, applied for a Special Use Permit to do so. Geologists would conduct ground-level seismic analyses of the ground below and also drill up to 150 feet below the surface. Currently, the operation proposes ten drilling sites.

The water could help Aurora meet the needs of a rapidly-expanding city while capturing water rights Aurora already holds, Baker said. He estimated the reservoir could be completed in 25 years if key steps were met, including a geological analysis.

The Whitney Reservoir project drew early attention from Colorado River conservationists and a fishing association concerned for the health of local fish habitats and the river system. Prolonged drought and existing diversions have already diminished Colorado River flows in recent decades.

The project could also impact pristine wetland ecosystems and would also require cutting near 500 acres from the Holy Cross Wilderness.

Members of the public can find more information about the project on the U.S. Forest Service website. Comments can be made any time but will be “most helpful” if submitted before June 30, 2020, the Forest Service said in an information release…

To comment on the project, or propose a different course of action, submit a comment online at https://cara.ecosystem-management.org/Public/CommentInput?Project=58221.

River diversion will eliminate portaging — The Leadville Herald

A river project, partially funded by the CWCB on the Arkansas River at Granite. The project was removing a river-wide diversion structure and replacing it with a new diversion structure that will allow unimpeded boating through Granite. Photo credit: Brent Gardner-Smith/Aspen Journalism

From The Chaffee County Times (Max R. Smith) via The Leadville Herald:

In the mid-1960s, a partnership between the cities of Colorado Springs and Aurora installed a diversion dam in the Arkansas River south of Granite near Clear Creek Reservoir as part of a pipeline system bringing water from the western slope of the Continental Divide to the Front Range.

The presence of the diversion dam caused that portion of the river to be non-navigable, requiring portaging of one’s raft or kayak.

By the end of this year, however, Colorado Springs Utilities is on schedule to complete a three-year project to build a new river diversion that will allow boaters to float right through, meaning that the 2020 rafting season will be the first in over 50 years in which the entirety of the Arkansas can be travelled without portage.

“We’ll see how the snow treats us over the next couple weeks, but we’re really down to some final boulder work in the river and general site cleanup at this point,” said CSU project manager Brian McCormick.

The intake that pumped water out of the Arkansas (which, legally speaking, comes from the Eagle River Basin as part of the Homestake Project), destined for Aurora and Colorado Springs, “as with anything in the river for 50-plus years, it took some wear and tear,” McCormick said. “By about the mid-2000s, the cities recognized we needed to rehabilitate this structure to keep it as a reliable facility and ensure safety of the river users.”

Construction on the new $9.1 million diversion project began in 2016 after a number of years of planning, budgeting, and engineering. Support for the project included $1.2 million in grant funding from the Arkansas Headwaters Recreation Area, Colorado Parks and Wildlife and the Colorado Water Conservation Board…

Significant to water consumers in Colorado Springs and Aurora, the project utilizes a new intake and piping structure to send water to the Otero pump station, he said.

Significant to boaters is a chute constructed of boulders and mortar with six two-foot drops that will allow them to pass the intake facility without exiting the river. McCormick said that CSU put the call out to members of Colorado’s river recreation community to participate in a trial run down the chute in November, testing the Arkansas’s newest whitewater feature…

Significant to the scaled, Omega-3 rich denizens of the Arkansas who swim upstream to spawn every year, the new diversion also features a fish ladder: a sequence of weirs and pools that give brown and rainbow trout a route to move up the river to their spawning grounds.