BIG PIVOTS: Reimagining Colorado’s Highways

PHOTO: Wildlife migration overpass on Highway 160, between Pagosa Springs and Durango.

This essay appeared on Big Pivots on January 14, 2023.

Although never a big-game hunter, I have killed three deer in Colorado and likely gave a bull elk a terrific headache. That’s not to mention my carnage among rabbits and other smaller critters.

Cars were my weapon, not guns.

Driving at dusk or into the darkened night will inevitably produce close brushes with wildlife, large and small, on many roads and highways. Even daylight has its dangers.

Colorado is now redefining that risky, ragged edge between wildlife habitat and the high-speed travel that we take for granted. State legislators delivered a message last year when appropriating $5 million for wildlife connectivity involving highways in high-priority areas.

In late December, state agencies identified seven locations where that money will be spent. They range from Interstate 25 south of Colorado Springs to Highway 13 north of Craig near where it enters Wyoming. New fencing and radar technology will be installed. Highway 550 north of Ridgway will get an underpass.

The pot wasn’t deep enough to produce overpasses such as two that cross Highway 9 between Silverthorne and Kremmling or one between Pagosa Springs and Durango. But $750,000 as allocated to design work for crossings of I-25 near Raton Pass with a like amount for design of an I-70 crossing near Vail Pass.

In this and other ways, Colorado can better vie for a slice of the $350 million allocated by Congress in the 2021 Infrastructure Investment and Jobs Act for improved wildlife connectivity.

This is on top of the overpass of I-25 planned for the segment between Castle Rock and Monument to complement the four underpasses installed in the widening project of recent years.

We are pivoting in how we regard roads and wildlife habitat. We have long been driven to protect human lives and our property by reducing collisions. Our perspectives have broadened. Human safety still matters, but so do the lives of critters.

Before, says Tony Cady, a planning and environmental manager for the Colorado Department of Transportation, highway safety for people was the highest priority —and conservation for wildlife a distant second. “Now we’re seeing much more of a wedding or marriage of those tow values, safety and conservation.”

A 2016 study of western Colorado identified highest-priority road segments in red.
A 2022 study showed even more road segments in eastern Colorado owing at least partly to higher traffic volumes.

Biologists in the 1990s began emphasizing highways as home wreckers. Expanding road networks, they said, was creating islands of wildlife habitat. Fragmented habitat leads to reduced gene pools and, at the extreme, to the threat of extinction of species in some areas, called extirpation.

I-70 became the marquee for this. Wildlife biologists began calling it the “Berlin Wall to Wildlife.” The aptness of that phrase was vividly illustrated in 1999 when a transplanted lynx released just months before tried to cross I-70 near Vail Pass. It was smacked dead.

With that graphic image in mind, wildlife biologists held an international competition in 2011 involving I-70. The goal, at least partially realized, was to discover less costly materials and designs.

Colorado’s pace has quickened since a 2014 study documenting the decline of Western Slope mule deer populations. Also helpful was creation of the Colorado Wildlife and Transportation Alliance, a consortium of the state’s transportation and wildlife agencies along with federal land agencies and non-profit wildlife groups.

In 2019 an incoming Governor Polis issued an executive order to state agencies directing them to work together to solve road ecology problems.

Two wildlife overpasses along with underpasses and fencing north of Silverthorne completed in 2017 have been valuable examples. Studies showed a 90% reduction in collisions.

“An 80% to 90% reduction right off the bat is pretty typical for these structures,” says Cady

Beginning in 2016 for the western half of the state, data have been crunched to delineate the state’s 5% highest priority road segments. These data may give Colorado a leg up on access to federal funds.

The two studies found 48 high-priority segments in western Colorado and 90 in eastern Colorado, reports Michelle Cowardin, a wildlife biologist for Colorado Parks and Wildlife. The Craig and Meeker areas have lots of high priority roads, but so is much of I-76 between Fort Morgan to Julesburg.
Eastern Colorado wildlife and highway corridors

Some jurisdictions are diving deeper. Eagle County has completed a study of wildlife connectivity, and Pitkin County has secured funding for a first-step study that will identify highest-priority locations in the Roaring Fork and Crystal River valleys.

These new studies attest to a shift in public attitudes and a shift within the state agencies. Cady says that highway engineers still think about human safety first, but there has also been a shift.

“I think the mindset has shifted in the last four or five years. We are not having to justify the inclusion of wildlife components in projects. It’s more understood that these are necessary components.”

To be clear, remediation in Colorado is mostly done as part of road projects. The work on Highway 160 between Pagosa and Durango, for example, came in at $11 million, of which only $3.5 million went to the overpass and also an underpass as well as other measures with wildlife in mind.

Projects also tend to have multiple funding sources. For example, the Southern Ute Tribe provided $1.5 million for that project near Pagosa. The project on Highway 9 in Middle Park included $4 million from a local rancher.

Rob Ament of Montana State University’s Western Transportation Institute says wildlife connectivity is becoming institutionalized in how we think about transportation corridors. Instead of motivated solely to minimize risk to humans, there’s growing appreciation of the needs of wildlife, too.

He says crossings are becoming a cost of doing business.

This is happening internationally, too. “My world is just exploding,” he said while reciting crossings for elephants in Bangladesh, tigers in Thailand and work for other species in Argentina, Nepal, and Mongolia.

Allen Best

Allen Best

Allen Best publishes the e-journal Big Pivots, which chronicles the energy transition in Colorado and beyond.