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Mountain News: New plans for dismantling the 'Berlin Wall' to wildlife

VAIL PASS, Colo. —In the late 1990s, people concerned about wildlife mortality took to calling Interstate 70 the Berlin Wall to wildlife in Colorado. They had hard evidence for the name.
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There are now efforts to create both overpasses and underpasses on sections of Interstate 70 in Colorado, which has been nicknamed the "Berlin Wall" for the threat is has posed to wildlife. HIGHWAY HAZARD

VAIL PASS, Colo.—In the late 1990s, people concerned about wildlife mortality took to calling Interstate 70 the Berlin Wall to wildlife in Colorado. They had hard evidence for the name.

In 1999, lynx were reintroduced into Colorado, at locations in the San Juan Mountains. On a hot summer day just a few months later, one of them was squashed on I-70 near the summit of Vail Pass. It had wandered several hundred kilometres north, but it could not get across the freeway.

In 2004, a wolf had wandered south from Wyoming across the Red Desert and several mountain ranges. Once in Colorado it could not get across I-70. Its carcass was found near Idaho Springs. It was the first confirmed wolf in Colorado in decades.

Now come new efforts to continue to create both overpasses and underpasses on Vail Pass.

On the west side of Vail Pass, wildlife mitigation will be included in plans for building 16 kilometres of auxiliary lanes between Vail and the summit of the pass. John Kronholm, a design team manager for the Colorado Department of Transportation, said discussion with stakeholders has settled on two larger underpasses—for deer, elk, and moose—and several smaller underpasses, such as for lynx. The science behind what will work best continues to evolve, said Kronholm, but the underpasses range from simple corrugated metal arches to concrete boxes.

The environmental assessment will be wrapped up next spring, he said, but nothing will be final until both C-DOT and the Federal Highway Administration sign off on the plans. But funding is another matter. It's behind several other even more expensive projects planned to increase the capacity of I-70 between Denver and Summit County.

East of the summit of Vail Pass, one overpass and two underpasses have been identified as necessary to provide landscape connectivity for a breeding population of lynx as well as other species. The structures, if built, would be on the west-bound lanes, as the east-bound lanes have several broad spans, essentially bridges, that allow wildlife to pass underneath.

Vail Pass has been identified as a high priority by Summit County Safe Passages, a coalition of local, state, and federal agencies, plus private companies and environmental and other advocacy organizations.

Julia Kintsch, a consulting conservation biologist, says preliminary engineering and cost estimates will likely begin before summer's end. That work will be paid for with US$190,000 in funding from Vail Resorts and Arapahoe Basin (all Mountain News funds are in U.S. dollars). The two ski area operators had been required to pay for wildlife mitigation projects relative to impacts caused by their terrain expansions, in the case of Vail Resorts for its expansion at Breckenridge.

As on the west side of Vail Pass, no money has been allocated for construction. However, Kintsch points to the partnerships with Summit County Safe Passages as foundational for future work. The diversity of government and non-government partners "can really accelerate these types of projects," she said.

Highway 9 between Silverthorne and Kremmling provides an example of partnerships at work. The Colorado Department of Transportation wanted to straighten and widen a 17-kilometre segment of the highway between Kremmling and Green Mountain Reservoir. It's a valley thick with sagebrush and large populations of mule deer and occasionally elk during winter.

Lingering memories of a 1985 accident were a motivation for the highway upgrade. A pickup driving on the two-lane highway swerved—to avoid hitting a deer, the driver said—and smacked head-on into the compact car carrying Gene and Mimi Ritschard. The couple, who lived on a ranch along the Colorado River, had been driving home from a water meeting. They died instantly.

Paul Jones, the wealthy owner of the Blue Valley Ranch, near where the tragedy occurred, donated $1 million to get the planning and fundraising going. The Colorado Department of Transportation itself said the money had to come from elsewhere. Jones donated another $4 million and other private citizens donated $2.1 million, Grand County gave $3.1 million, and other local governments—Kremmling, Silverthorne, and Summit County—added $360,000.

This produced two overpasses, five underpasses, tall fences to funnel the deer to the crossing structures, and other infrastructure.

Evidence has been accumulating of the success. In the five years before 2015, when the structures were mostly installed, roadside surveys revealed an average 56.4 carcasses per year. Since then, the surveys have yielded six carcasses per year.

With those and other statistics in store, Summit County Safe Passages approached the Summit County commissioners with a proposal. Safe Passages has identified two more crossings on Highway 9 in addition to the work on the east side of Vail Pass as high priorities. One overpass would be between Green Mountain Reservoir and Silverthorne, and the other between Breckenridge and Hoosier Pass. Both would benefit deer, elk, moose, and other large animals.

Kate Berg, a senior planner for Summit County, said the goal of a resolution proposed for adoption by the commissioners would be to incorporate the critical wildlife passages into the county master plan and other documents.