SAVING DARK SKIES
There’s a growing push to preserve celestial views over rural Colorado as artificial light spills out of cities
Silent stars sparkle across the night sky and reflect off alpine snowfields like scattered diamonds, a treasure southwestern Colorado towns are mobilizing to protect as never before by declaring dark zones. Celestial views from remote spots, such as this pass at 11,530 feet in the San Juan Mountains, measure almost totally free of the artificial light that increasingly blots out starry skies in cities worldwide. At the opposite extreme, metro Denver measures 100 times brighter than natural darkness and, since 2006, the brightness increased by a factor of at least 16, according to sky quality records kept by local astronomers. The push in Colorado to designate large-scale dark-sky preserves, and reduce urban light pollution, is widening and gaining momentum amid a greater pandemic-driven focus on a long-neglected part of the natural environment. Night skies never gained the federal legal protection Congress established in the 1970s to limit human degradation of the air, land and water.
But scientists since then have determined that excessive artificial light causes biological harm,
“We consider it a blessing that we can go out at night and see stars. We have our dark sky. We want to keep it.”
Crestone Mayor Kairina Danforth
impairing the basic functions of wildlife, plants and people. The American Medical Association warned in 2016 that blue LED light, in particular, disrupts sleep rhythms and may raise risks of cancer and cardiovascular disease.
For decades, population growth and development in the Rocky Mountain West has brought steadily more blinding glare, sky glow and other forms of light pollution — as in Denver, where utility crews are installing 44,000 high-intensity white street lights and video billboards that flash at drivers downtown and en route to Denver International Airport.
NASA photos of Colorado from space show a widening urban glow reaching into rural areas. Metro Denver residents who wanted to see the recent Geminid meteors and conjunction of Jupiter and Saturn had to leave the city for better viewing. Artificial night light has reached such intensity that dark sky advocates now are drafting legislation to set state-level limits. They’re also exploring lawsuits to stop the nuisance of so-called “light trespass.”
It wasn’t always like this. Colorado’s high elevation and dry air naturally favor clear views into an unfathomably infinite panorama — the constellations that ancestors identified as bears, a dragon, seven sisters, a hunter.
One of those ancestors gifted in reading the sky and making prayers “was my grandma,” said Bryan Vigil, 68, a Marines war veteran and Jicarilla Apache elder living just south of Colorado in Dulce, N.M., who often rolls through the San Luis Valley.
“She used to put a quilt on the ground on a hill. We used to lay there. She told us that was the North Star, the Big Dipper, the Milky Way. She told us when the morning star was going to come up. She’d tell us things that were told to her when she was young,” Vigil said. “At nighttime, it’s a different world. A lot of things happen at night. Some people see coyotes, the wolf.
“But this dominant society, the white people, brought artificial stuff including lights. It makes people go out at nighttime, looking for trouble or what they are curious about. And it all goes against my ways.”
Saving dark skies in rural areas
The dark-sky zones that southwestern Colorado leaders are proposing would, all combined, cover more than 3,800 square miles — the largest official area protected from artificial light on the planet.
Community campaigns have multiplied from Interstate 25 west through the San Luis Valley and across the Continental Divide toward southeastern Utah. Largely south of the Arkansas and Gunnison rivers, these dark-sky zones potentially could meld with preserves in Utah and New Mexico.
Colorado’s tourism promoters have hopped aboard, preparing branding material (“Colorado Stargazing: Experience the Night”) to lure more visitors and money.
And Gov. Jared Polis backs the effort.
“The dark sky initiatives are great, of scientific importance and also recreational importance for so many Front Range residents who want to go watch meteor showers,” Polis told The Denver Post.
Designating an official dark-sky zone requires approval by the Arizona-based International DarkSky Association, which guides communities through lighting overhauls and sky quality meter measuring to verify darkness. For two decades, association officials have encouraged grassroots action to save starry skies as researchers track the expansion of Earth’s artificially lit area by an estimated 2.2% a year.
Local governments must sign off to win approval. And heavily lit hot spots such as Alamosa, Cortez, Durango and Monte Vista, as well as big box stores, gas stations, car dealerships and marijuana grow houses, present challenges.
Astronomer John Barentine, the International Dark-Sky Association’s policy director, called Colorado’s growing efforts “extremely forward-looking” and smart, promising ecological, economic and health benefits at a time when most Americans, from where they live, cannot see the Milky Way.
“Among the Lower 48 states, natural nighttime darkness may already be extinct east of the Great Plains, with the possible exceptions of the Boundary Waters region of northeast Minnesota, the North Woods of Maine, parts of the Adirondack Mountains of upstate New York, and isolated pockets elsewhere. To find large expanses of darkness, you have to look at the dozen or so remaining pools in the West or interior Alaska,” Barentine said in an interview.
Saving starry skies “is a worthwhile goal for many reasons: environmental, social and fiscal. A view of the night sky can soothe the soul. In an era when so many people are suffering from the sensory overload of modern life, as well as what psychologists are calling ‘nature deficit syndrome,’ the night sky offers calm, quiet contemplation. And we’ve seen more interest than ever during the pandemic, with people being isolated at home and some looking at the night sky for the first time.”
Efforts to preserve the night in Colorado
Colorado efforts took off in 2015 when the adjacent towns of Westcliffe (population 368) and Silver Cliff (population 565) won certification as dark-sky communities.
Town leaders steeped in a conservative ranching tradition supported broader economic development and, although wary of becoming a tourist trap, helped residents and businesses replace old lights with shielded fixtures that direct dim light downward. They also built an observatory, beyond the bowling alley, with a retractable roof and benches where stargazers can sit looking up.
Then, across the Sangre de Cristo Mountains, the 232-squaremile Great Sand Dunes National Park and Preserve in 2019 achieved a dark-sky park designation based on systematic measuring and adjustment of lights using campground motion sensors and wildlife-friendly yellow hues. Managers made similar overhauls and won dark-sky designations at the Black Canyon of the Gunnison National Park, Dinosaur National Monument, Hovenweep National Monument and Jackson Lake State Park. The town of Norwood (population 736) achieved darksky community status in 2019, followed by Ridgway (population 992) last year.
Mesa Verde National Park and more towns — including Crestone, Cuchara, Paonia, Pagosa Springs, Naturita, Nucla and La Veta — have dark-sky zone applications “in the pipeline,” International
Dark-Sky Association staffers said. A San Luis Valley coalition proposes to create a 3,000square-mile Sangre de Cristo Dark Sky Reserve on mostly public land from Poncha Pass to New Mexico.
Meeting the dark-sky association’s standards for managing artificial light can take years. Some towns face potentially prohibitive costs to fix overly bright and misdirected lights. And local governments must forge consensus to deal with the problem of proliferating super-bright porch and yard lights.
“We consider it a blessing that we can go out at night and see stars. We have our dark sky. We want to keep it,” said Crestone Mayor Kairina Danforth, who has been participating in meetings convened by leaders around the San Luis Valley for coordinating efforts.
Large landowners have embraced dark-sky preservation, along with federal wildlife refuge managers concerned about cues for wildlife foraging, breeding and migration, Danforth said. An astrophysicist has proposed construction of a research observatory on the Colorado College satellite campus near Crestone.
The challenge has been “the ordinances, which can mean regulating property owners who want to light their property as they wish. Some elected officials are reluctant. Some of their constituents say, ‘It’s my constitutional right to light my property however I wish.’ But the surprising thing overall is how widely this protection is accepted,” she said. “And, ultimately, peer pressure from neighbors to preserve dark night skies is far more effective than any ordinance.
“We talk about conserving our land, water and air. So why don’t we add more protections for our dark skies?”
Western values and common courtesy
In Creede (population 300), dark-sky proponents refining a proposal from 2016 now are mulling a wider effort to designate all of Mineral County — 878 square miles west of the San Luis Valley — as a dark-sky preserve.
Traditional Western values prevail in this area, where turning off outdoor night lights already is engrained as common courtesy, said Heather Greenwolf, director of the Headwaters Alliance that coordinates local efforts.
“We don’t live in fear and anxiety of the wilderness down here. We already have a culture, a way to protect our dark skies in perpetuity,” Greenwolf said.
For example, Creede Repertory
Theater managers switch off lights at 10 p.m. The operators of a 40-acre RV park catering to visiting Texans recently dialed back. School board members agreed to review lighting at their buildings. And Tomkins Hardware and Lumber clerks help homeowners find dark-sky-friendly fixtures.
“Everybody out here loves the stars. It’s an easy sell,” Greenwolf said. “We do not want to be Vail.”
If just the proposed 3,000square-mile Sangre de Cristo Dark Sky Reserve is certified, Colorado would be home to the world’s largest dark-sky designated area, surpassing the 2,123square-mile Mont Megantic preserve in Canada.
An Alamosa-based civic group called San Luis Valley Great Outdoors is preparing a formal application, operations director Patrick Ortiz said, noting federal public land managers appear supportive.
“We have a good chance of getting this approved. It makes sense to get it done now. We could expand it later,” Ortiz said. “We don’t want to be like the Front Range. We want to grow gradually on our own terms.”
Fighting light pollution in cities
Meanwhile, dark skies advocates also are mobilizing to try to restore starry skies inside those Front Range cities.
Since 2016, membership in the Colorado chapter of the International Dark-Sky Association has tripled from 50 to 180. Public health and safety legislation being drafted by advocates for lawmakers to introduce this year would set tougher standards in building codes for protecting dark skies and set environmental regulations designed to reduce light trespass.
A building boom and more people moving to metro Denver, combined with city policies that have prioritized the cost-saving economics of LED retrofits, have jacked up brightness by more than 16 times since 2006, said University of Denver astronomy professor and observatories director Bob Stencel, a coordinator for the dark-sky association’s activities in the state.
“The changeover to LED lighting — public and private — results in a lot of higher-energy blue light, and blue light scatters a lot more than yellow and red light,” Stencel said, blaming street lights for about one-third of Denver’s light pollution. “It can disrupt sleep and affects flora and fauna. We’re not seeking to abolish night lighting, but to reduce the excessive levels and fix misaimed lights.”
Denver leaders in 2019 approved a $1.6 million streetlight overhaul, directing Xcel Energy to replace old amber sodium lights with 44,000 LED lights — 34,000 so far have been installed — as a way to cut annual maintenance costs.
City engineers had raised concerns about the change, warning of the impacts on night darkness and circadian rhythms. The first street lights considered were too bright. Public works officials conferred with city sustainability strategist Sonrisa Lucero and chose softer LED lighting and fixtures that direct light downward.
Yet in 2019, city agencies still received 120 complaints that the lights were too bright. Xcel crews resolved most complaints by dimming and redirecting street lights, and in some cases removing them. City agencies also recorded 16 requests for installation of new lights and eight for brighter lights.
Lawsuits against governments over what’s called “light trespass” have increased nationwide in recent decades as artificial night light spreads, a Harvard law student’s 2018 study found, with most complaints filed by residents alleging too much light.
Courts generally have found public benefits sought by governments outweigh harm. But governments apparently aren’t legally obligated to ensure bright street lighting. Legal disputes between residents often aren’t recorded, and Stencel said parties typically settle out of court.
While law enforcement agencies traditionally favored artificial light at night, some police now distinguish between steady dim lighting that increases visibility and bright misdirected light that creates shadows where criminals potentially could hide.
Denver officials have not set any citywide goal for restoring dark skies. But this will be possible, Lucero said, as residents and officials develop a broad climate warming resilience and sustainability plan this year.
“It is something I’m passionate about,” she said.
Fighting the “light bombs”
Ryan Parker, president of the Colorado chapter of the International Dark-Sky Association, recently stood in an empty parking lot at the Castle Rock Outlets shopping complex, lamenting the “light bombs” glaring atop poles and a video billboard next to Interstate 25 flashing advertisements for garments.
“They leave these lights on even when nobody’s here. It doesn’t make any sense,” said Parker, a real estate agent who has found homebuyers increasingly value dark skies.
For years, he has been lobbying south suburban governments to reduce light pollution. When new homeowners in Douglas County’s Sterling Ranch community recently complained about excessive lighting, developers initially balked. But they embraced a darksky-friendly redesign and now host forums where they advise residents to shield and dim their outdoor lights and turn them off when not needed.
Yet farther south along I-25 in once-dark woods near Larkspur, a video billboard flashes all night, and lights around new housing units spill across habitat that federal wildlife officials designated as critical for an endangered jumping mouse. East of I-25, utility crews have been replacing old yellow lights at high plains ranch houses with unshielded high-intensity white LED systems.
Humans evolved without artificial light at night. “And now we’ve created an environment where we want to be out doing something when we should be sleeping. There’s a reason why we sleep at night. Too much light is not good. We need light for security and to be able to see our way. We don’t need so much light that it messes with our sleep patterns and nature,” Parker said.
“I get it. It is your land. You can do what you want on your land. But if you don’t want people treading on you, don’t tread on others with your light.”