Wednesday, April 14, 2021

Centerline rumble strip construction to begin

| April 6, 2021 12:00 AM

The Montana Department of Transportation will begin installing low noise centerline rumble strips on highways in western Montana this spring.

The project is anticipated to begin in early April, with dates still to be determined. Flathead, Lake, Lincoln, Mineral, Missoula, Ravalli, and Sanders counties all will see construction this spring and summer. Lake, Ravalli, and Sanders counties also will see roadside improvement work, with the state updating signs and shoulder rumble strips.

Traditional rumble strips are grooves in the pavement that produce a rumbling noise and vibration when a vehicle drives over the strip. Shoulder rumble strips have been utilized on Montana’s highways for decades to alert drivers veering off the side of the road. Low noise rumble strips are now being installed along the centerline of undivided highways to continue improving the safety of Montana’s highways.

Low-noise rumble strips still cause noise and vibration to alert the driver. Yet, they are much less audible outside the vehicle, making them less disruptive to people living along highways.

“The technology of rumble strips has greatly improved, allowing for a much quieter experience for those in the vicinity of the strips, yet they are just as effective as traditional rumble strips and a proven cost-effective solution for reducing serious injury and fatal crashes," said John Schmidt, construction engineer for the Missoula district.

Low-noise rumble strips are designed to prevent roadway departure crashes, particularly head-on and sideswipe crashes that occur when a vehicle crosses the centerline of an undivided highway into the oncoming lane of traffic.

Schmidt noted that studies from other states where rumble strip projects have been implemented showed a reduction in roadway departure crashes by as much as 42% and severe injury crashes by as much as 73%.

During construction, traffic will be slowed but not stopped and routed around the work zones. During paving, there will be traffic stops with pilot cars.

A map of the installation areas can be found at