Nitrogen and ammonia, largely generated by heavy traffic along the Front Range and by agriculture in Larimer and Weld counties, are carried by air currents to the highest elevations of the treasured national park and deposited by rain and snow onto sensitive alpine tundra, where thin soil and delicate plants struggle to buffer the pollution.

If the contamination worsens, wildflowers could disappear and algae could bloom in alpine lakes, changing the waters’ look and endangering fish, scientists told The Denver Post.

“This issue gets worse as you go up in elevation as the sensitivity gets higher,” Jim Cheatham, an environmental protection specialist with the National Park Service’s air resource division, said during a recent meeting with Colorado’s Air Quality Control Commission.

Over time, the excess nitrogen — largely from vehicle exhaust — acts as a fertilizer to plants and changes the ecosystem, said Jill Baron, a research ecologist for the U.S. Geological Survey and senior research scientist at Colorado State University.

“You’re fertilizing Rocky Mountain National Park,” Baron said. “But you don’t really want to fertilize a national park.”

Baron, who has spent her career studying excess nitrogen’s effect on the park, said she has seen the beginnings of algae growing in mountain lakes because they are getting nutrients from increased nitrogen in the air.

“It’s a change from pristine conditions,” she said. “We are not at the bright green and stinky stage yet, but we are at the beginning.”

The point of creating national parks was to preserve pristine land across the United States, so scientists want to protect Rocky Mountain’s natural beauty and prevent as much human-caused change as possible, Cheatham said.

“The tundra is the primary resource the park was created to protect,” he said.

Over the years, state and federal air quality regulators have managed to reduce the amount of wet nitrogen — how the main pollutant is identified once it becomes trapped in rain or snow — that drifts into the park. But the amount of wet nitrogen falling in the park is 0.6 kilograms short of a 2022 goal of 2.2 kilograms per hectare per year, according to an Aug. 15 milestone report presented to the Air Quality Control Commission.

Ammonia pollution exceeds nitrogen

One component of wet nitrogen — nitrogen oxides — has been reduced since the project began nearly 20 years ago.

However, ammonia — which is also a form of nitrogen — has increased, according to the Rocky Mountain National Park Initiative’s 2022 Nitrogen Deposition Milestone Report. In fact, ammonia is now a bigger pollutant in the park, exceeding nitrogen deposits since 2013.

The push to clean the air in the Rocky Mountain National Park began in 2004 when the Environmental Defense Fund and Trout Unlimited petitioned the federal government for improvement. Over the years, the U.S. Environmental Protection Agency and the Colorado Department of Public Health and Environment have created plans to reduce air pollution that damages the park’s ecosystem.

This project is different than another effort to reduce the haze that is visible from Rocky Mountain National Park and other federally protected areas. That haze is created by severe ozone pollution in the region. And Rocky Mountain National Park isn’t the only Colorado park impacted by the haze.

Every five years, scientists from the National Park Service and the state health department present a report to the Air Quality Control Commission, which establishes rules to regulate air pollution in the state. The most recent report was presented in August, and the next one is due in 2029. The latest Rocky Mountain National Park Initiative report is open to public comment until Sept. 23.

In between reports, scientists monitor the park’s air quality and work with various partners, including the Colorado Livestock Association and Colorado Dairy Farmers, to figure out ways to reduce pollutants flowing into the park.

The bulk of the nitrogen pollution comes from the nitrogen oxides produced by burning fossil fuels through driving gasoline-powered cars and trucks, as well as oil and gas production.

Rocky Mountain suffers from the same severe ozone pollution seen in metro Denver and the northern Front Range, Cheatham said. So any attempts to improve air quality through emissions reductions in lower elevations will help the park.

Scientists have recorded a 15% reduction in nitrogen pollution in the past five years, Cheatham said.

However, ammonia pollution has increased, with the highest recorded levels occurring in 2021, according to the presentation given to the air commission.

That pollution is generated by agriculture, primarily in Weld and Larimer counties. Cattle waste, particularly from feed lots, contains ammonia and fertilizer poured onto crops contains nitrogen. Overall, the number of beef cattle in the region increased between 2018 and 2022, which was the period studied, and the number of dairy cattle reached maximum capacity in 2021, according to the latest report.

In the spring and fall when upslope weather patterns carry air from the south and southeast into the park, the ammonia from the cows is swept into the mountains, said Jeffrey Collett Jr., a CSU professor of atmospheric science.

“All of these things get pushed up the slope of the mountains,” Collett said. “As that happens, the air is expanding and cooling and you often form clouds, and that results in heavy precipitation.”

Agriculture in Larimer and Weld counties generates more than $2.5 billion annually for Colorado’s economy, according to an Aug. 15 presentation by Bonnie Laws of the Colorado Livestock Association.

Preserving “icons of pristine national beauty”

Beef producers and dairy farmers want to do their part in reducing emissions and protecting the national park, but it’s a tricky balance, Laws said during her presentation.

“Sometimes when you control air emissions you could end up creating a water quality problem or you could end up with practices that increase greenhouse gasses,” she said.

Farmers and ranchers try to reduce pollutants by being more efficient with food or fertilizer that contains nitrogen. The more difficult challenge is finding ways to minimize it on the back end.

One of the tools available is an early warning system for agriculture producers that notifies them when an upslope storm is in the forecast. The producers receive emails and text messages days ahead of the predicted storm so they can change how they manage their livestock.

For example, a feedlot manager could hold off on cleaning big manure piles, which kicks up ammonia, or change their pen cleaning schedules until the storm passes, Collett said.

Some are testing whether wetting a pen’s surface ahead of a storm reduces the amount of pollutants lifted into the air. Others are looking at whether changing the nitrogen and protein in animal feed would make a difference.

“There are people working on trying to test these different practices to find ways to reduce these ammonia emissions without impacting their ability to produce beef or milk or whatever their goal is in the operation,” Collett said.

Megan McCarthy, a senior air quality planner with the state health department, said the combined efforts are slowing the potential damage to the park and the various agencies and organizations involved are a one-of-a-kind effort in the country.

Baron, the ecologist, said there are some things, such as large-scale global warming, that cannot be controlled by people in Colorado. But efforts to reduce nitrogen oxides emissions statewide not only help the park but also people who suffer from respiratory ailments.

“Catching it early rather than waiting until it’s a crisis has been very helpful,” she said. “These parks are important to the American people as well as all over the world. The lakes themselves are icons of pristine national beauty. It’s one of the few places on Earth where things are protected.

“Those things are fixable if we have the social and political willpower to do so.”

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The injured hiker, who couldn’t walk, was taken to the Aspen Valley hospital Thursday night to be treated for injuries that were not life-threatening.

The caller telephoned for help after leaving the Maroon Bells Wilderness Area and gaining cell service.

Two Mountain Rescue Aspen teams of six rescuers mobilized and reached the fallen hiker around sunset, Pitkin County Sheriff authorities announced in a press release.

The hiker was on a three-mile scenic loop that connects to Maroon Lake with the East Maroon Portal.

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Because of their love for the area and their impact on Glacier Basin – to improve the fishing in the area for his guests, Abner dammed the creek to create the lake – the lake now bears their surname. And because of the busy Sprague Lake Lodge they operated from 1910 to 1940, there are many trails to explore in the vicinity, which became Rocky Mountain National Park in 1915.

One of those trails is the Glacier Creek Trail.

This trail isn’t so much a single trail but a network of paths through the forests surrounding Sprague Lake. Adventurous hikers may want to take the long way around, starting at Sprague Lake, Glacier Basin Campground (if camping) or the Storm Pass Trailhead.

Shorter hikes can be done as a loop around Sprague Lake, up onto the moraine above the lake and down into the forest, taking the turn off to the right rather than heading to Storm Pass Trailhead.

A really wonderful option for a full-day hike is to start at Sprague Lake, pick up the Glacier Creek Trail at the east end of the lake, follow it east into the forest and then turn right to follow it back west again towards Bear Lake.

The network of trails parallel Bear Lake Corridor, navigating past many meadows in this valley, and up to Bear Lake. At Bear Lake, follow the eastern side of the lake to pick up the Bear Lake – Bierstadt Lake Trail, following it to Bierstadt Lake and then down to the Bierstadt Lake Trailhead. From this point, cross the road to the Storm Pass Trailhead and pick the Glacier Creek Trail back up on the forest and head east to Sprague Lake.

At about 8 miles, this loop provides some astonishing views plus many opportunities to see wildlife, like mule deer, snowshoe hare, elk, pine squirrels, northern flickers, Stellar’s jays, dark-eye juncos and many other species of forest-loving birds.

For a shorter trek, take the two-mile loop that starts at the east end of Sprague Lake. Near the bridge, the trail heads down into the forest, snaking through ponderosa pine and past a lush green meadow.

At about a half mile, the trail reaches a junction, where hikers turn right. Follow this trail as it begins to climb up the moraine. In about 500 feet, the trail reaches the Glacier Creek Trail, which runs northeast and southwest. Turn right at this junction to head towards Boulder Brook and Bear Lake.

Follow the trail, which is now the Glacier Creek Trail, for 1.1 miles as it stays along a level path on the moraine through thick forest and above meadows.

At slightly more than one mile, the trail reaches another junction, connecting with the Storm Pass Trail. Make a right at this junction.

Interestingly, the trail crosses the Alva B. Adams Tunnel at this point. This 13-mile cement-lined tunnel passes underneath Rocky Mountain National Park to deliver water from Lake Granby to East Portal on the west side of Estes Park. There are no markers or indicators of what lies beneath the ground but using the COTrex app will show you the path of the tunnel below the trail.

In 0.3 miles, the trail reaches a four-way junction, with connections to Glacier Creek, Storm Pass, Bear Lake, Bierstadt Lake and Glacier Gorge trails. Take a right and follow the trail through the thinner forest.

At 0.2 miles, the trail reaches the Sprague Lake parking lot on the west end of Sprague Lake.

This section of RMNP requires a timed entry reservation from 5 a.m. to 6 p.m. until October 20. The hiker shuttle bus takes hikers into the Bear Lake Corridor but does not stop at Sprague Lake. A park pass is also required to enter Rocky Mountain National Park.

For more information about timed entry or hiking in RMNP, visit https://www.nps.gov/romo/index.htm.

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First responders were alerted to the injured woman around 5:30 p.m. by hikers using emergency communication devices, Grand County Search and Rescue officials said in a post on Facebook.

Other hikers initially provided first aid before realizing the woman needed more medical care and contacted the Grand County Sheriff’s Office.

Search and rescue crews arrived on the trail just before 10 p.m., provided first aid and transported the injured hiker to an area where an emergency medical team could take over care. She was taken to the Middle Park Medical Center for treatment.

More information about her condition was not immediately available.

This is a developing story and may be updated

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CFI, which uses automated infrared counters on several peaks and statistical modeling estimates on others to develop its annual estimates, said the number of 260,000 in 2023 was the lowest since 2015 when the nonprofit began its annual estimates.

The closure of the Decalibron Loop, which includes three popular fourteeners near Fairplay, was one factor in the decline, but numbers fell in several other areas as well.

“Hiking Colorado’s fourteeners last year was like stepping into a time machine and coming out in 2015,” CFI executive director Lloyd Athearn said in a news release. “After six seasons of increasing use, it has been all downhill since 2020. Closure of the Decalibron loop for half the season was the biggest factor, but use was down last year in three of Colorado’s seven ranges containing fourteeners, including the popular Front Range closest to the Denver metro area.”

The Decalibron loop was closed in 2023 due to landowner liability issues, which have largely been resolved with the passage of Senate Bill 58 this year. That legislation provides legal protections for landowners who allow the public to recreate on their land.

Athearn said it’s hard to know what is driving the decline, but he has two theories: Slower population growth in Colorado and changing age demographics.

Colorado’s population grew nearly 15% from 2010 to 2020, according to census figures, but the influx of newcomers slowed over the past two years. Also, Athearn suspects that the baby boomers who popularized backpacking and peakbagging are aging out of the fourteener culture.

“My Millennial colleagues — another massive generation — are buying houses, having kids and taking on more work responsibilities,” Athearn wrote in a follow-up email. “That likely translates into less time or money to get out to play regularly. Meanwhile, my son is in that Gen Z age group. While his friends are all pretty athletic and outdoor-oriented, I know many of his peers are not.

“We may be in a period of shifting age booms and busts,” Athearn added, “where those who have been large cohorts of active folks with time, money and health to be out climbing peaks are now facing lack of time, money or compliant bodies to do this physically demanding stuff.”

As usual, the two most popular fourteeners in 2023 were Mount Bierstadt and Quandary Peak, both of which were estimated to be in the range of 25,000 to 30,000. Bierstadt’s number usually comes from an infrared counter, but it was stolen last year, for the second year in a row, after being in operation for only six days. Quandary’s counter recorded more than 29,000. CFI’s “best-guess” numbers put Mount Elbert at 22,000, with Grays and Torreys at 21,000.

The Decalibron loop, which was in the range of 20,000 to 25,000 in 2022, fell to something between 7,000 and 10,000, CFI said.

The Colorado Fourteeners Initiative, which is based in Golden, was created in 1994 to protect and preserve Colorado’s 14,000-foot peaks through stewardship and education.

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But when they woke up, they saw a plume of smoke rising into the sky. Darren Wilson had anticipated something like this, even before their trip began.

“It was in the back of my mind — I hope we don’t hike into somewhere and get trapped by a fire,” recalled Wilson, a Hamilton, Montana, resident.

They were hiking through the Anaconda Pintler Wilderness and knew it was under strict restrictions: No building campfires, no fire allowed anywhere, no exceptions. The summer had been dry and hot, and wildfires had been erupting throughout Montana.

But as the group continued hiking toward Hidden Lake, they realized the trail of smoke ahead might be the early stage of a wildfire.

The hikers weren’t trapped, but 200 yards from Hidden Lake they came upon scorched earth surrounding a tree split down the middle, most likely from a lightning strike. Its bark was blackened and glowing, and beneath the tree the charred ground smoldered. The smoke they’d seen was seeping from beneath hot charcoal and dry wood.

“You could tell the tree torched and burned while it was standing and then cracked and fell on the ground,” said Darren’s wife, Chelsie, an x-ray technologist with previous experience in wildland firefighting.

“I think everyone had different feelings,” she said. “Those who had never seen forest fires before were panicking.”

The group put Chelsie Wilson in charge, and she laid out a two-step process: Some people would run to Hidden Lake to fill every water bottle and hydration pack. Everyone else would use the water to turn the smoldering dirt into mud.

Chelsie Wilson and Brittney Erickson, one of her fellow hikers, poured water on dirt, using the wet earth to put out the fire bit by bit. Chelsie kicked a burning stump into the ground. The team smothered it. She instructed and delegated jobs, describing the team as willing, communicative and diligent.

“It was really scary at first,” Chelsie said, “and then it became fun.” After two hours, she gave her team the all-clear. They had transformed the patch of smoldering char into a wet pile of dirt and debris.

On a hike later the same day, the group climbed West Pintler Peak only to spot another fire, this one on the horizon some 10 miles away. They called in the sighting from a ridge with cell service and heard a plane fly low overhead the next day. Weeks later, they said they think that was the first alert to the Johnson Fire, a 270-acre blaze southwest of West Pintler Peak.

If there was a theme to the hikers’ trip it was definitely fire, because while camping near the bank of Oreamnos Lake, they spotted wispy smoke billowing from the opposite shoreline.

“We start yelling across the lake, top of our lungs,” Darren Wilson said. “‘Is there anybody there? Do you have a fire?’” Hearing no response, they initiated a then-familiar course of action. Gathering every container of water they possessed, the group rushed toward the smoke’s source.

“Like children of the corn, we come out of the trees,” Wilson said, only to find three men huddled around a prohibited campfire. The hikers explained that they’d put out a smoldering wildfire, spotted another and were worried about a third — the campfire they were now looking at.

“The guys were not very impressed with us, though,” Chelsie Wilson said, as the men reluctantly extinguished their fire. “They didn’t like our story at all.” Still, they’d agreed to douse the fire and the hikers withdrew, hoping this was the end of fires popping up on their trekhike.

“It’s a real possibility,” Darren Wilson said. “You could be caught behind the wrong side of a fire.”

Zeke Lloyd is a contributor to Writers on the Range, writersontherange.org, an independent nonprofit dedicated to spurring lively conversation about the West. He lives in Helena, Montana and writes for the Montana Free Press.

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Searchers using dog teams found the missing 67-year-old man’s body in a scree field near the trailhead, according to a Boulder County Sheriff’s Office news release. A team from the Rocky Mountain Rescue Group recovered the body.

The man’s identity will be released by the Boulder County coroner.

The man was hiking, climbing and camping in the area of the Middle St. Vrain trailhead, near the Camp Dick Campground in the Indian Peaks Wilderness Area north of Nederland. He was supposed to return on Thursday but when he did not come home his family called the sheriff’s office.

The sheriff’s office initiated a search after deputies found the man’s vehicle in the trailhead parking lot, the news release stated.

The sheriff’s office does not suspect foul play.

The man is the second missing hiker found dead in Boulder County in a week. A 36-year-old man was found dead after he failed to return from a camping trip in the Indian Peaks Wilderness near Brainard Lake.

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For 25 years, 10 city and county governments near the former nuclear weapons manufacturing site northwest of Denver have monitored for contaminants and other hazards through their participation in the Rocky Flats Stewardship Council. But now the council, which has met regularly to discuss conditions on the troubled property-turned-wildlife refuge is disbanding.

Broomfield pulled out earlier this week, joining Golden, Superior, Thornton, Northglenn and Boulder County in abandoning the council — a sufficient number of member defections to trigger the organization’s demise. The body will hold a final meeting this fall, clear the books and dissolve by early next year.

Deven Shaff, a Broomfield city councilman who has sat on the stewardship council for the past five years and serves as its vice chair, said its death doesn’t mean concerns about Rocky Flats will go away.

“You have an end to the stewardship council, but there is a story ahead for Rocky Flats,” Shaff said. “There’s a sense that there’s a new chapter for Rocky Flats.”

That new chapter could begin as soon as next week, when construction is set to start on two regional trail access points at the edge of Rocky Flats National Wildlife Refuge. Looming over the project is a potential ruling from a federal judge that could halt plans to build the planned underpass and bridge, which will bring the Rocky Mountain Greenway trail onto the refuge.

The stewardship council’s demise and the continuing controversy are the latest developments in the long and tortured history of Rocky Flats.

The weapons manufacturing facility opened in 1952 and made plutonium triggers — or fission cores — for the nation’s nuclear arsenal throughout the Cold War. On a windswept piece of Jefferson County prairie between Arvada and Superior, the ugly result of all that industrial activity was the creation of tons of hazardous chemicals and barrels of noxious waste, some of which leaked or burned over the years.

Rocky Flats, which employed about 40,000 workers over its nearly 40-year active phase, was closed down after the FBI raided the plant in 1989. It sent 70 armed agents in a convoy of vehicles to the U.S. Department of Energy property to ferret out suspected environmental crimes.

“No way” everything was cleaned

Despite a 10-year, $7 billion cleanup that ended in 2005, many remain leery of what Jon Lipsky, one of the lead FBI agents during that raid — and an outspoken critic of Rocky Flats for years — calls an “unlicensed nuclear dump.”

“There’s all sorts of infrastructure that exists underground, and nobody knows what’s there,” Lipsky told The Denver Post. “There’s no way the Department of Energy cleaned everything.”

The Rocky Flats Stewardship Council is compromised because the Department of Energy funds it and “runs interference” for it, Lipsky said. That’s a sentiment shared by the Boulder-based Rocky Mountain Peace and Justice Center. Chris Allred, who works on nuclear issues for the center, said there needs to be an organization that can look out for public health “without being subject to regulatory capture by the DOE.”

The peace and justice center is not convinced that the 6,500-acre site, which opened as a national wildlife refuge six years ago, is safe for human recreation. It’s one of several environmental groups that sued the federal government in January in an effort to stop the trail connections from being built on Colorado 128 and Indiana Street.

About 1,300 acres in the middle of the refuge remains a Superfund site, off-limits to the public, where the plutonium triggers were manufactured inside what amounted to a small standalone city.

“Rocky Flats is not stable in the environment,” Allred said. “This will only be made worse if construction projects are allowed to continue spreading contaminated dust.”

Dave Abelson, the longtime executive director of the Rocky Flats Stewardship Council, flatly rejects the claim that he is bought and sold by federal interests, saying his accusers “have not shown a single example of where the funding source affected the actions or comments of the board or of the contract staff.”

“Not a single instance,” he said.

Abelson agrees that it’s time for the organization to sunset — not because it’s untrustworthy, he says, but because the science says so.

Water samples from the site have been relatively stable and within a safe range for years, while hundreds of soil samples — with the exception of one that generated headlines five years ago for its elevated plutonium reading — have also been deemed safe.

“Do you need the same type of intense focus that the governments have put on this?” Abelson said. “The answer appears to be no. You don’t need the same level of focus because it’s a stable site and has been for many years.”

Concern about lack of collaboration

The stewardship council grew out of the Rocky Flats Coalition of Local Governments, which was launched in 1999. The council, created in 2006, was a more formal version of its predecessor and was created under a mandate in federal law to provide local communities a voice in the management and monitoring of contaminated sites nationwide.

The council has proven vital in looking for and identifying post-cleanup problems at Rocky Flats, Abelson said.

One year, city and county officials on the council challenged a plan by DOE officials to breach ponds on the site. They also expressed concern with the condition of Rocky Flats’ notorious landfills.

“The governments were alarmed when it became clear that portions of the original landfill that lie above Woman Creek were not stable,” Abelson said. “DOE eventually remedied the problem.”

In more recent years, things have been quieter, said Thornton Mayor Jan Kulmann, who chairs the stewardship council. She’s served on the body for a decade.

Thornton’s main concern is water quality, she said, with Standley Lake — just east of Rocky Flats — serving as a major source of drinking water for the city of 145,000.

“The data that we’ve been receiving from DOE … have not changed in 10 years,” Kulmann said. “We’re cautiously optimistic that it has reached a more stable condition.”

Broomfield’s concerns are different than Thornton’s, given its closer proximity to the refuge.

The city and county has been aggressive in separating itself from all things Rocky Flats in recent years. It started in February 2020, when the city’s elected leaders unanimously voted to pull out of the Jefferson Parkway Public Highway Authority following the discovery in 2019 of an elevated reading of plutonium along Indiana Street and in the path of the proposed highway.

Not long after that decision, Broomfield withdrew from the Rocky Mountain Greenway project, resulting in the trail being rerouted through Westminster. But Broomfield Councilwoman Heidi Henkel isn’t so sure the city should have withdrawn from the stewardship council without having an “exit plan.”

“The only way to make government accountable is (that) you make everything public,” said Henkel, who served on the stewardship council for two years. “It’s disappointing to me that with a Superfund site there, we’ve decided to stop this group without any commitment to further the public discussion.”

While the Department of Energy will send quarterly water quality reports to the cities and counties that made up the stewardship council’s membership, Henkel worries about the lack of collaboration and shared knowledge that comes from everyone sitting down at a table together.

50,000 visitors to Rocky Flats

Seth Kirshenberg, executive director of Energy Communities Alliance, said the cities and counties around Rocky Flats are in a unique position because their advocacy organization — the stewardship council — is one of the first in the country to disband.

His Washington, D.C.-based group works with communities that are located near former nuclear weapons plants and nuclear energy facilities.

“Remedies fail and you have to keep on top of these issues,” Kirshenberg said. “The remedies need to be protective of human health and the environment. Hopefully, all we see is the use of the site — but if something happens in the future, they may have to put it back together.”

A Department of Energy spokesman told The Post that the agency would continue doing what it has been doing while the stewardship council has been active.

“The cleanup of the Rocky Flats site has proven to be protective of human health and the environment for nearly 20 years,” spokesman Jeremy Paul Ortiz wrote in a statement. “As we move into the third decade since cleanup, DOE will continue reporting on-site monitoring and maintenance activities and post this material on our public website.”

The Rocky Flats National Wildlife Refuge saw 50,000 visitors in the most recent fiscal year, according to the U.S. Fish and Wildlife Service.

One of those visitors is Jeanette Hillery, a member of the League of Women Voters of Boulder County. She’s also been a member of the stewardship council since its inception 18 years ago.

She said she’s struck by how the contamination horror stories of decades ago still seem to guide people’s thinking about Rocky Flats today. The site isn’t pristine, she said, but the testing and data she has seen over the last two decades indicate the risk posed by Rocky Flats’ legacy is more than manageable.

“There are a lot of people who want to go back to the 1970s and 1980s — and think that what was going on then is still going on today,” Hillery said. “The testing indicates it’s safe.”

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The U.S. Forest Service announced this week that Colo. 5, known as the Mount Blue Sky Scenic Byway, will close on Tuesday to all motorized and nonmotorized traffic, including cyclists and pedestrians.

The Federal Highway Administration is ready to begin a roadway construction project that will keep the beloved summit road closed until the spring of 2026, according to this week’s announcement.

Visitors still have an opportunity to reserve times to visit the byway and the summit of the 14,266-foot peak, but time slots are limited and in high demand. To make reservations to visit the summit, the Mount Goliath Natural Area or Summit Lake Park, visit recreation.gov. The areas are open from 8 a.m. to 6 p.m. Reservations must be purchased before arrival due to a lack of cell service at the welcome station.

“As one of the most visited recreation areas on the Arapaho and Roosevelt National Forests, Mount Blue Sky draws visitors from across the world. So far, more than 45,000 vehicles booked timed-entry reservations for the 2024 season,” Forest Service officials wrote in the news release.

The roadway project will close Colo. 5 from the gate near the Forest Service welcome station up to the summit parking lot. If conditions permit, the road is expected to reopen for Memorial Day weekend in 2026.

During the interim, the Mount Blue Sky summit will only be accessible via hiking trails, Forest Service officials say.

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What it lacks is adequate creek access for visitors to stop and savor its beauty or hike along its banks. The highway, U.S. 6, is off-limits to runners and cyclists because its five dark tunnels are so narrow, and pullouts are scarce — with some posing traffic dangers. Motorists get only occasional glimpses of the soaring canyon walls above because the curving highway commands their full attention.

That’s going to change over the next two years, thanks to an ambitious construction project that will dramatically improve recreational access to the canyon. Jefferson County’s Open Space division is spending $80 million to extend the Clear Creek Canyon trail three miles upstream from its current terminus at Tunnel 1, which is located two miles west of Golden. About 1.25 miles of new trail is slated to open just west of Tunnel 1 next year, with another 1.75 miles to follow in 2026. Eventually the trail will connect with Clear Creek County trails through Idaho Springs and beyond.

If $80 million seems like a lot for three miles of concrete trail, it is. But the complexity of the project, with a narrow creek and highway hemmed in by steep mountainsides, presents major engineering hurdles. In some sections, the trail is being built on elevated concrete viaducts resembling the sweeping roadway decks of Interstate 70 as it runs through Glenwood Canyon.

The project includes seven new bridges over Clear Creek, one new bridge over the highway, a new underpass beneath the highway and two new trailheads with restrooms and parking spaces for 170 cars. A park at one of the trailheads will feature a one-mile loop for hikers and creek access.

“It’s pretty wild,” project manager Scot Grossman said while providing a guided tour of the area in mid-August. “What we’re doing is a generational project.

“This has statewide and national significance,” he continued. “We’re creating safe access to the creek, as well as all the recreational amenities – rock climbing, slack-lining, tubing, rafting, fishing, gold panning. I love the idea of little kids growing up in Golden 15 years from now, they get their little bike posses together on Saturday and ride up the trail to go fishing, climbing, or to ride a lap at Centennial Cone (park) and ride back down.”

“We’re building this for 100 years”

Great Outdoors Colorado — which distributes Colorado Lottery proceeds — provided a $7-million grant for the current construction project. The Denver Regional Council of Governments chipped in another $10.25 million. GOCO previously gave the Clear Creek Canyon trail effort $10.5 million for segments that have already been completed.

But the remainder of the $80 million is coming out of the Jeffco Open Space budget, which is funded by a dedicated 0.5% sales tax that voters approved in 1972. That tax is not subject to the restraints of the TABOR amendment, approved by Colorado voters in 1992, which limits the amount of revenue governments in the state can retain and spend.

“Most of the open space programs around the Front Range have a similar sales tax,” Grossman explained. “Ours predates Tabor by 20 years or so, so there’s no sunset (provision) on it, which is really fortunate for us. Other agencies have a 10- or 15-year sunset, and they have to go back to the voters to re-up their funding.”

CDOT is also working on the project in an effort to create safer motorist access to creek attractions than has been the case in the past. “They’re the other landowner here,” Grossman said. “Their mission is to get people through the canyon safely and efficiently. Our visitors, when they stop, they pull out in every little nook and cranny. Doors open, dogs come out, strollers, bikes. It’s just not a safe environment to recreate in.”

In 1871 a narrow-gauge railway began service in the canyon from Golden to the mining towns of Clear Creek County. The current construction project takes advantage of some of its grades. Prior to the construction of Interstate 70 in the 1960s and ’70s, Clear Creek Canyon was the primary route to the mountains for Denver motorists. .

Now, Jeffco’s Clear Creek Canyon Park is in the process of stretching up the canyon along the creek from Golden to Clear Creek County. The first segment opened in 2021 with the debut of the $19-million Gateway trailhead just west of the intersection of U.S. 6, Colorado 93 and Colorado 58. From there, the existing trail extends 1.75 miles to Tunnel 1.

The Clear Creek Canyon trail will be the middle segment of the greater Peaks to Plains trail, which eventually will extend 65 miles from the foot of Loveland Pass through Georgetown, Idaho Springs and Clear Creek Canyon to the confluence of Clear Creek with the South Platte River in Adams County. It is already complete from the Clear Creek Gateway trailhead to the Platte, near 74th Avenue and York Street, via Golden, Wheat Ridge and Denver.

“We’re building this for 100 years,” Grossman said. “We really want to make sure this is here for three or four generations. That takes time. The geologic, ecologic and hydrologic challenges are immense. We have world-class whitewater here that gets really high in the spring. And, you can see the geologic constraints. We’re in a deep canyon with rock everywhere.”

A floating trail, like a mini-Glenwood Canyon

Construction manager Jeff Hoge, a cyclist, already is looking forward to exchanging his hard hat for a cycling helmet.

“I can’t wait for this,” Hoge said. “I’m a cyclist, I grew up here, and I’ve never been able to ride a bike legally on U.S. 6. That’s exciting. As far as the construction part of it, this is a dream job for a construction manager.”

The three-mile section now being built will climb 300 feet from Tunnel 1 to Huntsman Gulch. All of it will be wheelchair accessible and comply with the Americans with Disabilities Act, which means maximum grades of 5%. The walls of the canyon soar 1,000 feet over the creek, which often is very narrow, which is why construction engineers opted for building a viaduct through those sections. It also has less impact on creekside vegetation, they say.

“This is a heavy civil construction project, but we really pride ourselves on having a really light touch, a really surgical approach, because at the end of the day we are an open-space organization,” Grossman said. “We’re a balance of recreation and conservation.

“That viaduct, I think, perfectly sums up ‘heavy civil’ with a light touch. That is a difficult thing to engineer and build, but the impact on the land is way smaller and lighter than cutting out (a streamside slope) and filling back in,” he added.

To create the viaduct supports, workers drill 30 to 40 feet through surface rock and soil until they reach bedrock. Then they drill another 12 feet into bedrock to anchor concrete columns that will support the deck on which more concrete will be poured for the trail.

“This is our new tool, a ‘floating trail,’ a mini-Glenwood Canyon — same design principles,” Grossman said. “We’re basically building a 10-foot-wide road. It’s like what CDOT is doing on Floyd Hill right now — same concept, just smaller.”

The first new trailhead, about a mile upstream from Tunnel 1, will include a roadside parking lot that can accommodate 40 cars, along with a bridge over Clear Creek to the trail.The second new trailhead, at Huntsman Gulch, will offer a place to park, linger and explore which Grossman calls “a park within a park.” The parking lot will be built to handle 70 cars, and there will be a bridge across the highway to the trail. Another bridge will take visitors over the creek to a secondary trail accessing a shady one-mile hiking loop with a natural surface.

When the Huntsman segment is complete in 2026, it will leave a six-mile gap between Huntsman and a segment of the project upstream that opened in 2017, providing access to Jeffco’s Centennial Cone Park near the Clear Creek County line. Grossman said filling that gap, which would complete Jeffco’s part in the Peaks to Plains trail, could take another seven to 10 years depending on funding.

“This is a really big project,” Grossman said. “There’s a lot of money invested from taxpayers of all kinds — federal, state, local, people who play the lottery.

“I start every presentation I give with how privileged I am to do this, to have the responsibility – which is weighty – to do stuff like this for generations to come,” he added. “I’m just a nameless face three generations from now, but this is a legacy for all of us.”

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