Centerline Rumble Stripes

What are centerline rumble stripes?

Centerline rumble stripes (CLRS) are grooves between the double yellow centerline that create audible noise and physical vibrations when the tires of a vehicle drive over them. CLRS are similar in design to the shoulder rumble stripes and strips.

The sounds and vibrations of CLRS alert the driver that they have departed from their lane, giving the driver an opportunity to recover. CLRS also have an additional benefit of helping drivers navigate during weather conditions that produce poor visibility such as fog, snow, and rain.

Why is ARDOT installing centerline rumble stripes?

ARDOT is working to prevent lane departures that result in head-on collisions, side-swipe crashes from the opposite direction, and crashes that occur when a vehicle veers left off the roadway.

One of the leading causes of roadway departure crashes on Arkansas’ highways is vehicles crossing the centerline. In Arkansas alone, there were 164 fatal crashes in 2020 that were a result of drivers crossing the centerline.

CLRS are a proven safety countermeasure and were found to reduce cross centerline crashes by 40-60% in the Transportation Research Board’s (TRB) National Cooperative Highway Research Program (NCHRP) Report 641.

Finally, CLRS are one of the most economical safety measures available. The cost to install CLRS are very low, especially compared to the high payoff of saving lives.

Drivers, roads, & environment are common factors for lane departure crashes:

o   Young drivers
o   Sleepy drivers or “highway hypnosis”
o   Distracted driving
o   Speeding
o   Two-lane, undivided roads
o   Rural, high-speed roads
o   Weather conditions like rain, sleet, snow, fog, etc.
o   Curvy and hilly routes

How does ARDOT install centerline rumble stripes?

A programmed machine with a blade cuts the same shape, depth, width, and length into pavement. The impressions are 16 inches wide, spaced 12 inches apart, and follow along the centerline as shown:

ARDOT uses the following criteria to decide locations for centerline rumble stripes:

Speed

the speed limit is 50mph or greater

Roadway width

the combined width of the lane and shoulder must be 14 ft. or greater in each direction

Passing zones

CLRS should not deter passing within passing zones. Most crashes that occur when a vehicle drifts across the centerline are for reasons other than passing. Since crash location is random, all centerline areas are treated.

Two-lane rural roads

heavily populated and suburban areas are not considered for CLRS areas due to noise concerns and lower speed limits.

Do centerline rumble stripes raise noise concerns for rural highway residents?

Sound is measured in decibels. The goal is to increase the noise within the vehicle by 6-15 decibels to get the driver’s attention. The average measurement for a regular car driving on a normal surface is around 60 decibels. To give perspective, a hair dryer measures between 80-90 decibels.

Fortunately, noise from rumble stripes and strips occur infrequently and for a short duration. Think of the noise as “the sound of safety.”

How do centerline rumble stripes affect motorcycles?

CLRS add no measurable risk to motorcyclists and do not inhibit any passing opportunities. The Transportation Research Board’s (TRB) National Cooperative Highway Research Program (NCHRP) Report 641 provides ARDOT with the guidance for the safe design and application of CLRS as a crash reduction measure while minimizing adverse effects for motorcyclists, bicyclists, and nearby residents.

What can I do?

You can make all the difference by following these safety tips:

Do not drive while sleepy or under the influence
Adjust driving speeds for weather and conditions
Limit distractions and avoid using devices – the text can wait
Always wear your seatbelt
Drive defensively – give yourself time to react in case of an incident
Only pass in legal zones where there is adequate clearance distance between you and oncoming traffic