Highway crews replacing guardrail on hairpin curve where semis crashed

Construction crews with the Colorado Department of Transportation have begun replacing the guardrail on the outside edge of a hairpin curve in the southwestern mountains.

Two semis have crashed through the existing concrete barrier there since April.

Crews are installing a new larger concrete barrier that will be permanently anchored to the highway.

"The Cascade Curve has a steep downhill grade when traveling southbound," stated CDOT Regional Transportation Director Julie Constan in a press release. "Due to ongoing crashes, especially with commercial semi trucks, extra safety measures are needed."

A semi crashed on the curve April 17. Both lanes of the U.S. 550 were closed the next day to allow the rig to be safely pulled back to the roadway.

The second crashed occurred May 29. A tractor-trailer hauling pipe left the pavement and rolled into Cascade Creek. Both directions of travel were again closed most of the next day for recovery of the wreckage.

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The hope is that the permanent guardrail will deflect vehicles back onto the roadway or slow them down enough for the driver to recover control or even come to a complete stop.

The highway is reduced to a single lane of travel at the curve. Crews will work 7 a.m. to 7 p.m. weekdays. In off hours, a temporary traffic light system will control alternate directions. The project is scheduled to conclude sometime in November.

Cascade Curve is located two miles north of the Purgatory Ski Resort, midway between Durango and Silverton.