Ketchum-Challis Highway Project
Newsletter for November 2, 2017 (Acrobat, 656 KB)
What is the project, and where is the work taking place?
This project concerns reconstruction of approximately 1.216 miles of Forest Highway 26, better known as State Highway 75 (SH 75). SH 75 gives travelers access to the heart of south-central Idaho, noted for its rugged and historic scenery and recreational activities. The roadway also provides one of a few east-west links across central Idaho. The Ketchum-Challis Highway runs along the Salmon River in the Sawtooth National Recreation Area (Sawtooth NRA), just south of the border between Sawtooth NRA and the Salmon-Challis National Forest. The project follows the existing alignment from approximately milepost (MP) 206.7 to approximately MP 207.9. The project area includes a reach of the Salmon River known locally as Pebble Beach.
Why is reconstruction needed?
Frequent rockfall from steep and unstable cut slopes above the roadway poses a safety hazard to motorists. Fill slope instabilities below the road have undermined and narrowed the roadway, creating variable and substandard pavement widths. These conditions create safety concerns for the users of SH 75, a key state highway that provides access between communities in Custer County and Blaine County. As a roadway administered under the Forest Highways Program, SH 75 must provide safe and adequate transportation access to and through National Forest System lands for visitors, recreationists, resource users, and others.
What reconstruction is occurring?
Road reconstruction includes widening the existing road, stabilizing slopes prone to rockfall, installing cross-drain culverts with riprap outlet protection, and performing the secondary activities needed to support these actions. FHWA is constructing two 11-foot lanes with 2-foot shoulders. Guardrails will be installed towards the Salmon River to protect motorists from the steep slopes. The frequent and dangerous rockfall will be addressed through flattening of the slopes to a more stable slope angle and stabilize the surface of the cut slopes to reduce erosion and help in the reestablishment of vegetation.
Project Map (JPG, 173 KB)
Documents and Updates
|Project #||ID PFH 26(3)|
|Project Name||Ketchum-Challis Highway (Pebble Beach Section)|
|Location||Custer County, Sawtooth NRA, Sawtooth National Forest|
|Awarded to||Ascorp, Inc, dba Debco Construction|
|Award Date||June 13, 2016|
View Tabulation of Bids
Federal Highway Administration
Western Federal Lands Highway Division
610 East Fifth Street
Vancouver, WA 98661-3801