Road on Cottonwood Pass would be costly to upgrade
EAGLE COUNTY — Upgrading Cottonwood Pass between Garfield and Eagle counties to serve as a year-round alternate route during Interstate 70 closures through Glenwood Canyon would not only be costly but likely politically challenging to accomplish.
A near weeklong closure of I-70 through Glenwood Canyon due to a major rockslide, and continued daytime closures this week while crews are busy with cleanup and mitigation efforts, has resurrected some talk, at least on street corners and in social media circles, about improving the backcountry route.
“We’re talking a couple hundred million dollars to widen it for (interstate type) traffic,” Garfield County Commissioner John Martin said.
“And then you have to maintain it in the winter,” he said. “It would be a big challenge with some real conflicts to get the right of way. … It would be a tremendous project.”
Even just improving the route to paved county road standards would be in the range of $20 million to $30 million, he said, not to mention snow removal costs for a road that’s now closed during the winter.
When a similar rockfall incident in Glenwood Canyon six years ago resulted in another lengthy I-70 closure, Eagle County officials came up with a cost estimate at that time of more than $45 million just to upgrade their portion of the road.
The road over Cottonwood Pass climbs up Cattle Creek (Garfield County Road 113) from Highway 82 south of Glenwood Springs for about 10 miles before crossing from Garfield into Eagle County and continuing on CR 10A for another 15 miles to Gypsum.
The road tops out at 8,280 feet at the northwest corner of the Red Table Mountain portion of the White River National Forest, before dropping through about six miles of Bureau of Land Management land.
Therein lies another challenge — gaining federal approvals to upgrade a road that passes through critical wintertime wildlife habitat, and potentially opening the door for development.
“We have not had any significant discussions about Cottonwood Pass since the last time this happened,” Eagle County Communications Director Kris Friel said of the current situation with Glenwood Canyon.
“It’s possible we might have that conversation again, given the lengthy closure,” she said.
Currently, the pavement ends on the Garfield County side at the intersection of County Roads 113 and 121 (Coulter Creek). The county maintains and plows the road for another 2.5 miles from that point to the county line, and Eagle County plows from there to the last residential subdivision before the road is gated for the winter.
On the Gypsum side, the town and county maintain the road during the winter for a few miles up to the last residences on that side before the winter gate, Friel said.
According to Eagle County’s 2010 analysis, a two-lane paved road that could be maintained all year could cost $47 million or more. Even a two-lane gravel road could cost more than $40 million, due to the costs of buying land, hauling fill material and building the road to resist erosion and slides, the county determined.
A two-lane highway built to the standards of U.S. Highway 6 through the Eagle Valley would have cost $66 million or more in 2010 dollars, according to that study.
Ironically, Cottonwood Pass was studied in the 1970s as a potential alignment for I-70 into western Colorado instead of Glenwood Canyon. A Colorado Division of Highways’ Location Study Report done at that time estimated that sending the interstate over Cottonwood Pass would cost around $77.7 million, compared with $65.2 million for Glenwood Canyon.
It also would have required the acquisition of three times more land, displaced 125 families and business, mostly as the interstate passed through the south end of Glenwood Springs, and would have had numerous other impacts.
That study also dismissed a 42.1-mile climb north over the Flat Tops due to the risk of “extensive environmental damage,” the challenges of high elevation and a $338 million price tag.