Anyone driving on state Highway 75 between Stanley and Challis will encounter road construction at an area often referred to as the “Narrows.”
The work, a federally funded project officially known as the “Ketchum-Challis Highway Project,” is under way on a 1.25-mile section of highway between mileposts 205.4 and 206.7, which is about 16 miles northeast of Stanley. The project involves rockfall mitigation and highway reconstruction.
The project is administered by the Federal Highway Administration through the agency’s Western Federal Lands Highway Division. FHA has contracted Knife River Corp., through its Boise office, for the project at a cost of $9,888,525.
The project is now in its second year and could last into mid-summer of 2015.
The work involves widening the existing roadway, stabilizing slopes prone to rockfall, installing a drainage system and constructing retaining walls.
FHA reports on its website that the work is necessary because of frequent rockfall from above the roadway, which creates a safety hazard for motorists. Much of the work involves stabilizing the mountainside above the highway for rockfall mitigation.
Knife River reported in a news release this week that the road is restricted to one 12-foot lane because of the alignment and narrowness of the highway.
Furthermore, according to Knife River, work activities are ongoing Mondays through Fridays and that motorists can expect delays of up to 15 minutes. Flaggers or temporary signals are used to control traffic during all hours of the day, including overnight.
Knife River asks motorists to obey all posted traffic control signs, signals and flaggers and to be especially alert during hours of darkness and inclement weather.
The project is administered by the FHA, rather than the Idaho Transportation Department, because it is on federal land and much of the work is being done above or below the actual roadway.