OURAY, Colo. (AP) — The Colorado Department of Transportation says U.S. Highway 550 over Red Mountain Pass will remain closed indefinitely while workers are being brought in by helicopter to fix damage caused by a rock fall.

The department says a helicopter made two trips Thursday carrying workers who are fixing the highway. Crews are bringing rocks down by hand to make the highway safe.

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Rocks began tumbling onto the road Sunday evening, and by Monday the rock fall was described as continuous.

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The closure severs the only direct route from Ouray to Silverton, normally a 70-mile drive over Red Mountain Pass. A detour over Dallas Divide and Lizard Head Pass adds nearly 100 miles to the trip.

CDOT says an average of 2,200 vehicles a day use Red Mountain Pass.

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