Much of the work involved with widening Interstate 25 between Monument and Castle Rock is happening off the highway, as workers install wildlife fencing on both sides of the busy corridor.
Piles of fencing material -- old and new -- are visible along the highway just north of the El Paso/Douglas County line.
Ultimately, 15 miles of 8-foot-high fencing will go up on both sides of I-25, between Monument and Tomah Road, just south of Castle Rock.
"We've installed six miles on each side so far," said Paul Neiman, the Colorado Department of Transportation's project manager. "We started last summer and probably won't finish until the overall project is done in early 2020."
Neiman said the fencing is being placed along existing property lines and will connect to four bridges allowing deer and larger animals to cross the highway underneath.
"This is a safe type of fencing," he said. "If deer do try and traverse this fence, sometimes they do try to jump it if they're scared. But if they do, they won't get impaled by other types of fencing."
The fencing is similar to that already in place on a six-mile stretch of I-25 between Fountain and the Pikes Peak International Raceway -- an area with twice as many animal/vehicle collisions as the Gap.
CDOT data shows that such collisions -- mostly involving deer -- peaked in 2016, at 425 for Region 1 (including the Gap) and 926 for Region 2 (including the Fountain area).
In 2018, the most recent year CDOT data is available, collisions dropped to 318 in Region 1 and 651 for Region 2.
"It's hard to say whether the Gap construction is forcing animals toward or away from the highway," Neiman said. "But once we finish installing this fencing, we're hoping for a 95% reduction in collisions. This protects drivers and animals."
Neiman said there are challenges with installing so much fencing.
"Fortunately, most of it is in a rural area," he said. "But we have to build 22 special crossings to keep deer from using private driveways to get around the fencing."
Neiman said CDOT has hired a company to remove the old fencing and recycle it.