WSDOT began installing rumble strips on undivided highways in 1999 as a countermeasure for roadway departure crashes. Installations on the shoulders were intended to reduce run-off-the-road crashes, while centerline rumble strips targeted reductions in cross-centerline crashes. A March 2011 report detailed the performance of centerline rumble strips on Washington State highways. This study:
• Examines the combined effects of centerline and shoulder rumble strips.
• Details the performance of rumble strips on undivided highways in Washington State under a variety of conditions.
• Explores various traffic volumes, geometric conditions, lane and shoulder widths, and driver contributing circumstances.
• Compares various installation scenarios with shoulder and centerline rumble strip installation at different times, as well as simultaneous installation.
Washington (State). Dept. of Transportation. Development Division, Design Office
Rumble strips, Center lines, Road shoulders, Highways, Ran off road accidents, Head on collisions, Safety, Performance measurement, Accidents, Analysis.