Rumble Strips

Rumble strips are a proven method for decreasing roadway departure crashes for motorized vehicles; however, when not installed properly, rumble strips can be a serious danger to cyclists’ safety. Rumble strips can force cyclists into the travel lane with high speed traffic when installed on roads with little or no shoulder or down the middle of the existing shoulder.

We work to ensure that all road users––both motorists and cyclists––can safely enjoy America’s roads. We advocate for transportation agencies to enact rumble strip policies that provide a minimum of four feet of usable shoulder for cyclists and ensure the quality control of rumble strip installation.

Rumble Strip Best Practices

Based on Federal Highway Administration (FHWA) standards and the studies/reports noted below, these are the rumble strip best practices recommendations that provide the minimum standards to safely accommodate bicyclists:

  • Shoulder width: No rumble strips or stripes installed on shoulders less than four feet
  • Placement: Adjacent to or on the white line, providing a minimum of four feet of usable shoulder to the right of the rumble strip
  • Frequency: 10-foot gaps allow cyclists to navigate away from the shoulder if needed
  • Depth: 0.375 inches
  • Width: 5 inches
  • Length: 6 inches 
  • Center Line Rumble Strips: Both FHWA and AASHTO guidance recommends that agencies maintain 14 feet of pavement beyond the edge of the center line rumble strips where vehicles and bicycles are expected to share the lane. Four feet of shoulder should also be maintained for cyclists’ safety when installing center line rumble strips where there are already shoulder rumble strips. 

Federal Rumble Strip Guidance

The Federal Highway Administration (FHWA) released an updated guidance on rumble strips in the spring of 2010 which was a big step back for cyclists’ safety. Partnering with the League of American Bicyclists and the Alliance for Biking and Walking, we worked with the FHWA to improve their guidance for cyclists and a revised Technical Guidance was released in November, 2011. In addition, the FHWA Safety Office provides recommendations and additional studies  on accommodating all road users. 

Studies & Reports

Let Us Know: Planned Rumble Strips

If you know that rumble strips are planned for roads that are part of the Adventure Cycling Route Network or the U.S. Bicycle Route System, please email us at travel-initiatives@adventurecycling.org to let us know. Once installed, rumble strips are costly to remove and last for decades. We will work with the state or local transportation agency to ensure that cyclists are safely accommodated. 

Correct rumble strip application on US 20, Wyoming. Photo by Doug Robin.