Montana Department of Transportation

Malcolm “Mack” Long, Director


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Public Involvement

South of Boulder South project logo

South of Boulder South

Project Benefits

This historic road was initially built for wagons and horses. It wasn't designed for today’s vehicles. Construction of a new road will allow for maintenance and safety related opportunities. Below are some of the major benefits that drivers can expect.

Primary Project Goal – Decrease Maintenance

A stronger road with better driving surface will reduce maintenance.

  • The existing roadway lacks proper ditches and is not raised above the land to keep it from getting wet, which weakens the roadway and causes the damage pictured below.
  • To improve this, the new road will be raised slightly or have better ditching to prevent water from soaking the materials that keep the road strong.
  • The driving surface will be improved by using better materials.
  • New culverts will also keep water away from the road.
south of boulder south road one image

Other Maintenance Benefits

Reduced ditch maintenance:

  • Ditches will be improved to handle more water.
  • For ditches susceptible to erosion, like long steep hills, the ditches will be protected with rock to keep them from being washed out. This will also decrease sediment getting into the river and streams.

Little Boulder River crossing improvements:

  • Replacing two culverts with one big culvert will decrease debris from jamming and blocking the flow of water. It also lines up better with the natural path of the river.
  • The new design will provide better fish passage through the culvert.

Snow storage benefits:

  • A raised road and better ditches provide more snow storage capacity and will limit drifting.

New culverts throughout the project are designed to handle the flow of water. They are sized and located in the right place to do a better job and keep water further away from the road.

Secondary Goal – Improve Roadway Safety

Road Alignment

  • The road will generally stay in its current position, but it will be improved to meet current standards. Both the vertical grades and horizontal curves will be improved. This will allow drivers to see where they are going and to see what is coming at them. This is important as you need to be able to see far enough ahead to stop, if necessary.
    • For example, as seen in the photo below, drivers must be nearly at the top of the hill to see what is on the other side. This will be improved.
south of boulder south road two image
  • The slopes on the side of the road will also be improved for safety throughout the project. Improving the side slopes by making them flatter will decrease the chance that vehicles overturn or strike an obstacle if they happen to leave the road.
  • Culverts will also be extended further away from the edge of the road to provide more room for errant vehicles. As shown in the photo below, the culvert doesn’t provide any room for error if you leave the roadway (it doesn’t provide much room for the road base either).
south of boulder south culver image
  • Intersecting roads and driveways. Improving the sight lines for drivers at driveways and intersections will improve safety for drivers making the move onto the main road and those on the main road.