Montana Department of Transportation

Public Involvement

S-472 Blue Slide Road Repair
Sanders County

Project Overview

Blue Slide Road Project image

The Montana Department of Transportation is reconstructing a section of Blue Slide Road nine miles west of Thompson Falls that was severely damaged in April 2018.

Heavy spring snowmelt combined with heavy rain caused Cougar Creek to overflow and wash out the gravel beneath the pavement on Blue Slide Road.

Reconstruction of the roadway will occur in two phases.

PHASE 1 | Short-term fix to stabilize and open the roadway to traffic.
May — June 2018

  • Work will be conducted during the day between 7 a.m. and 7 p.m.
  • Traffic will be controlled with stop lights and/or flaggers.
  • After the first week to 10 days, one lane of traffic will be open.
  • Some full closures and detours may be necessary.
  • MDT will notify the community in advance of closures and detours.
  • Once open, motorists will drive on gravel surface and speed limit will be reduced.
  • At the end of June, two lanes of traffic will be open.

PHASE 2 | Long-term fix to prevent future damage.
July — Fall 2018

  • Complete full evaluation and identify issues that caused the damage.
  • Conduct environmental evaluation and hydraulic analysis.
  • Finish rock fall mitigation evaluation.
  • Host public open house to share Phase 2 construction plans.
  • Construction complete in Fall 2018.

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TEXT: BLUESLIDE TO 22828 | CALL: 406-465-3350 | EMAIL: