The Montana Department of Transportation (MDT) and Frontier West are rehabilitating the bridge that carries Secondary Highway 382 (S 382) over the Flathead River near Perma. This bridge was originally constructed in the 1960s and needs repairs. This project will extend the service life of this bridge.
Planned improvements include:
- Replacing damaged bearings and joints.
- Repairing bridge girders.
- Hydro milling and overlaying the bridge deck with new concrete.
- Painting portions of the steel superstructure to slow corrosion.
- Upgrading bridge railing and roadway approach guardrail.
- Resurfacing the pavement approaches on each end of the bridge.
- Adding advance warning rumble strips and signage for the intersection of S 382 with Montana Highway 200 (MT 200).
What is Hydro Milling?
Hydro milling is a technique that removes deteriorated concrete using high-pressure water. This process allows the contractor to remove the top layer of concrete without causing additional damage to the bridge deck.
Example of hydro milling.