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RUMBLE STRIP IMPLEMENTATION GUIDE:

ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

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TABLE OF CONTENTS

Introduction ......................................................................................................3

Rumble Strip Installation Considerations .........................................................5

Pavement ...........................................................................................................5

Center Line and Shoulder Longitudinal Joints...................................................6

Rumble Strip Types...............................................................................................8

Rumble Strip Maintenance ...............................................................................10

Maintaining Rumble Strips during 

Pavement Maintenance ...................................................................................10

Summary .........................................................................................................11

Where to Learn More.......................................................................................12
In an effort to save some of the 500,000 lives expected 

to be lost in roadway departures in the next 25 years, 

the highway community needs to move forward with 

installing rumble strips as appropriate. 

Photo: Thinkstock
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This guide serves to educate pavement engineers and safety engineers on pavement-related considerations 

for rumble strip installation on new and existing pavements. As practitioners determine where and how to install 

rumble strips, there are several pavement-related variables that need to be taken into account and addressed 

to ensure that they will not accelerate pavement deterioration.

Introduction 

Longitudinal rumble strips are an effective, low-cost 

countermeasure for preventing roadway departure crashes, 

including both run-off-road and opposing-direction crashes. 

Rumble strips1,2 are milled or raised patterns near the center 

line or edge line of the roadway that provide both an audible 

warning (rumbling sound) and a physical vibration to alert 

drivers that they are crossing into opposing traffic or leaving 

the roadway. Rumble strips placed underneath center line or 

edge line striping are often referred to as “rumble stripes.”

1 FHWA, “Technical Advisory T 5040.39: Shoulder and Edge Line Rumble Strips,” Revision 1, 

November 7, 2011. Available at: http://safety.fhwa.dot.gov/roadway_dept/pavement/rumble_

strips/t504039/

2 FHWA, “Technical Advisory T5040.40: Center Line Rumble Strips,” Revision 1, November 7, 

2011. Available at: http://safety.fhwa.dot.gov/roadway_dept/pavement/rumble_strips/

t504040/

Rumble Strip Basics. There are two main applications for 

rumble strips: 

• Center line rumble strips (shown in Figure 1) can prevent 

head-on collisions and opposite-direction sideswipes, 

which are often referred to as cross-center line crashes. 

FIGURE 1. Center Line Rumble Strips

Photo: ConnDOT

RUMBLE STRIP IMPLEMENTATION GUIDE:

ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

They are primarily used to warn drivers who are drifting into 

an opposing travel lane. While they are most often used on 

rural two-lane, two-way roadways, they can also be applied 

to multilane undivided facilities. Center line markings are 

typically placed on center line rumble strips, which have an 

added benefit of improving the visibility of the marking in 

wet conditions. Center line rumble strips have been shown 

to reduce head-on and opposite-direction fatal and injury 

crashes by 45 percent on rural two-lane roads.3

• Shoulder rumble strips and edge line rumble stripes 

(shown in Figure 2) are primarily used to prevent run-offthe-road crashes. They warn drivers that they are drifting 

onto the roadside. While shoulder and edge line rumble 

strips perform the same function, the placement sets them 

apart. Shoulder rumble strips are historically common on 

freeways and other divided highways, but the decision 

to use one or the other on two-lane roads is based on a 

3 D. J. Torbic, J. M. Hutton, et al., NCHRP Report 641: Guidance for the Design and Application of 

Shoulder and Centerline Rumble Strips, Transportation Research Board, National Cooperative 

Highway Research Program (Washington, DC: TRB, 2009), Table 67. Available at http://

onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_641.pdf

number of factors. The edge line rumble stripe aligns the 

rumble strip with the pavement marking, thereby improving 

the visibility of the marking in wet, dark conditions. By placing 

the rumble strip closer to the travel lane, it alerts drivers that 

they are leaving the roadway earlier. Shoulder rumble strips 

and edge line rumble stripes have been shown to reduce 

single-vehicle, run-off-road fatal and injury crashes by 36 

percent on rural two-lane roads. 4

Pavement Concerns Related to Rumble Strips. There are 

many pavement-related variables that play an important role 

in the successful implementation of rumble strips, such as: 

• Existing pavement condition and age, 

• Pavement type and thickness, 

• Location and condition of longitudinal construction joints, 

• Rumble strip type and installation, and 

• Maintenance techniques. 

Previously, there were concerns in the pavement community 

that heavy traffic or harsh weather conditions would cause 

pavement deterioration where milled rumble strips were 

present. In 2014, Ohio DOT conducted a nationwide survey 

of pavement engineers through the AASHTO Research 

Advisory Committee (RAC) in which the agency requested 

information from other States on pavement deterioration 

and maintenance issues with center line rumble strips. Most 

of the 24 responding States indicated only isolated locations 

experiencing accelerated pavement deterioration along the 

joint, and several comments indicated these were locations 

where the joint or pavement were not in good condition prior 

to installation of the rumble strips. 

4 Ibid. 

FIGURE 2. Edge Line Rumble Strips

Photo: Leidos
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

Snow plowing has little or no effect on milled rumble strips. 

Snow plow operators have indicated rumble strips are 

actually helpful to them in detecting the edges of the lane. 

In locations that plow snow, however, raised rumble strips are 

not recommended as the raised profile may be damaged 

during plowing. 

Rumble Strip Installation Considerations

It is possible for rumble strip installation to have little to no 

impact on new or existing pavements if several critical variables 

are properly considered. The following provides practices with 

respect to each of these variables from States with successful 

rumble strip installations.

Pavement 

Knowing pavement history – age, condition, type, and thickness 

– is important in determining whether existing pavements 

are suitable for standard rumble strip installation or if modified 

dimensions or types of rumble strips may be appropriate. This 

can become somewhat complicated in cases where one 

or more maintenance treatments have been applied over 

the original surface. Addressing existing rumble strips during 

pavement maintenance is discussed in the section for 

“Maintaining Rumble Strips during Pavement Maintenance. 

Age and Condition

Pavement condition should be considered before installing 

rumble strips in existing pavement. Although milled rumble 

strips do not typically cause issues when installed in 

pavement rated fair or better, in older pavements that show 

high degrees of deformation or cracking distress, the milling 

process can exacerbate existing issues. Michigan DOT milled 

rumble strips into asphalt pavements of all ages rated fair or 

better and found that very few issues resulted. Where milling 

existing pavement is not feasible due to pavement condition, 

agencies may consider installing raised rumble strips or profiled 

markings; however, it is likely that reduced safety benefits will 

be experienced if the dimensions of the raised rumble strips 

are significantly less than the milled dimensions.

Pavement Type and Thickness 

Rumble strips can be milled into both new and existing asphalt 

and Portland cement concrete (PCC) pavements. Keep in 

mind, however, that rumble strips are not normally applied to 

bridge decks due to the presence of rebar. 

All pavements (PCC, asphalt, ultra-thin asphalt, chip seal, 

micro-surfacing, etc.) need to have a minimum thickness of 

“bound” pavement material before rumble strips are installed. 

“Bound” pavement materials are a combination of all layers 

of the materials listed above but do not include cold-in-place 

(CIP) recycling. In general, the thickness of the most recent 

overlay needs to exceed the depth of the rumble strip so that 

the previous layers of pavement are not exposed, which would 

allow moisture to infiltrate and compromise their integrity. Due 

to the increasing interest and use of preventive pavement 

treatments, such as ultra-thin asphalt overlays, chip seals, and 

micro-surfacing, DOTs are experimenting with rumble strips, so 

knowledge on the topic continues to grow. 

Recent experience in Michigan has found that preventive 

maintenance treatments such as ultra-thin hot mix asphalt and 

micro-surfacing can be compatible with rumble strips. Microsurfacing and ultra-thin hot-mix asphalt overlays fill in existing 

pavement deformations such as ruts and rumble strips, but 

rumble strips can be cut into the overlay without significant 

delamination. 
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

Milling into a chip seal is more of a challenge, however. 

Washington State DOT’s guidance is as follows:

Placement of recessed lane markers and rumble strips is 

discouraged on [chip seal] roadways due to insufficient 

surfacing depth. If recessed lane markers or rumble strips 

are used, the existing [chip seal] surfacing should have 

a total thickness of [4 inches] which can include any 

combinations of [chip seal] and [asphalt] applications. 

[Milling] rumble strips on [chip seal] roadways exposes 

the previous layers of [chip seals]. Exposure to moisture 

accumulation and freezing and thawing often leads to 

delamination. To reduce the possibility of delamination 

occurring at rumble strip locations, rumble strips shall be 

[milled] followed by the [chip seal] application.5

It is best to apply chip seal after rumble strips have been 

installed rather than before; however, the chip seal will 

reduce the rumble strip dimensions by the size of aggregate 

used, thereby reducing their effectiveness. An agency may 

wish to consider somewhat larger rumble strip dimensions if 

application of a chip seal is expected within a few years of 

installation. 

States have slightly different requirements for pavement 

thickness to ensure the pavement integrity is not compromised 

by rumble strip installation. Some States specify requirements 

based on pavement age. In Pennsylvania, for example, 

pavement that is new or less than a year old is deemed suitable 

for rumble strip implementation if asphalt pavement thickness 

is at least 1.5 inches. Existing concrete pavements, however, 

must have a minimum overlay depth of 2.5 inches. Other 

States have general requirements without age specifications, 

5 Washington Department of Transportation, Pavement Policy, (WSDOT: June 2011).

as shown in Table 1. When milling asphalt, it is important to 

ensure that the thickness of the top lift exceeds the depth of 

the rumble strip, otherwise there is a risk of compromising the 

integrity of the overlay when the rumble strips are installed.6 It 

is typically preferable to adjust the depth of the rumble strip 

rather than to eliminate this safety feature.

Table 1: Required Pavement Thickness for Rumble Strip Implementation by State

State Required Pavement Thickness for Rumble Strip Installation

Missouri 1.75”

New York 2.5”

Pennsylvania Less than 1 year old –1.5” 

Older – greater than 2.5”

Texas 2.5”

Washington 3”

Center Line and Shoulder Longitudinal Joints

In NCHRP Report 641, Tables 6 and 7 illustrate that States and 

territories handle the location of rumble strips in relation to 

the center longitudinal joint or shoulder joint very differently. 

In surveys and interviews, many States have indicated that 

the locations of the joints are not typically deciding factors 

in determining whether or not center line, shoulder, or edge 

line rumble strips should be installed. In addition, most States 

indicate very limited problems with rumble strips that cross 

joints, except where joints are already in poor condition. Where 

there is a concern for pavement condition, agencies may use 

a lateral offset to avoid cutting the rumble strips directly into 

the joint using the methods described below. 

6 E.R. Russel and M.J. Rys, NCHRP Synthesis 339: Centerline Rumble Strip – A Synthesis of Highway 

Practices, Transportation Research Board, National Cooperative Highway Research Program 

(Washington, DC: TRB 2005).
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

For center longitudinal joints:

• Nebraska places two 8-inch rumble strips (one on either 

side of the center line joint) with a 4-inch gap between.

• Michigan uses a pattern for the center line rumble strips 

that skips every third rumble strip to reduce pavement 

impact on the joint. 

For the travel lane/way and shoulder joints:

• The most typical lateral offset that States strive for is around 

4 inches from the travel lane/shoulder joint. 

• Pennsylvania DOT offsets rumble strips based on the width 

of the shoulder. If the shoulder width is between 5 and 6 

feet, the rumble strip is offset from the travel lane and is cut 

into the shoulder surface; if the shoulder width is less than 5 

feet, the rumble strip is offset from the shoulder and cut into 

the travel lane surface, as indicated in Figure 3. 

Missouri DOT reports avoiding the shoulder joint to some 

extent, although the agency has not actually found issues with 

milling through the joint when it is not possible to offset the 

rumble strips. 7 

7 Interview with John Miller, Joe Jones, Ashley Reinkemeyer, Michael Curtit, and John Donahue, 

Missouri DOT, conducted on June 5-6, 2013.

FIGURE 3. Pennsylvania DOT Shoulder Rumble Strip Section View
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

Rumble Strip Types

Rumble strips in the United States are typically milled into 

the pavement. In areas that do not plow snow on regular 

basis, raised designs are also used, While most States have 

developed a standardized shape with certain dimensions for 

each of the primary types, the installation techniques do allow 

significant flexibility. In general, wider strips will create a more 

sustained noise and vibration, and strips that are deeper (or 

higher in the case of raised designs) will provide more vibration 

and noise to alert the driver. Variations in other dimensions 

can also have a substantial impact on the safety effectiveness 

of the treatment, but have not been widely used or studied. 

Milled Rumble Strips

Milled rumble strips are made by a machine with a rotary 

cutting head that creates a consistent shape and size groove 

into the pavement. An example of milled rumble strips can be 

seen in Figure 4. The milling machine head used to install rumble strips can be 

modified to cut the exact desired dimensions, spacing, and 

shape of agency-specified rumble strips into the pavement. As 

with any construction operation, having an agency inspector 

and the contractor together at the onset of the milling operation 

is a key to successful rumble strip installation. Inspectors 

should be aware that the effective depth of the rumble strip is 

measured to the highest point within the bottom of the groove, 

the depth to which the tire will drop, rather than to the lower 

surfaces where the milling teeth cut, as illustrated in Figure 

5. Inspectors also need to consider where measurements 

will be taken if different slopes are involved. In sections with 

crown, center line rumble strips will be deepest at the center 

if the tires of the milling machine straddle the crown, or may 

taper off on one side significantly if both tires are to one side. 

FIGURE 4. Example of Milled Rumble Strips

Photo: FHWA

FIGURE 5. Measuring Milled Rumble Strips

Photo: FHWA
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

This can also occur on shoulder rumble strips if the shoulder 

has a different cross-slope than the main line, as shown in 

Figure 6. Together, the inspector and contractor can assess 

different milling techniques to meet the needs of the 

site conditions. 

Agencies should specify cleaning and disposing requirements 

for milled debris within the contract. For example, some 

agencies require debris to be swept, collected, and discarded 

after rumble strips have been installed. Other agencies may 

allow millings to be discarded by sweeping debris into the 

roadside. 

In terms of the length of time it takes to install rumble strips, 

several contractors report being able to place between 2.5 

and 4 miles of rumble strip per hour, resulting in the application 

of 20 to 32 miles of rumble strips in an 8-hour workday. 

Raised Rumble Strips

Raised rumble strips are typically 2- to 12-inch wide rounded 

or rectangular markers or strips that are fastened to new or 

existing pavements with epoxy. Some road agencies use 

products that can be inlaid with the thermoplastic pavement 

marking. Heights also vary based on the product used. However, 

all are restricted to warmer climates that do not require snow 

removal because, to be effective, they must be above the 

surface of the pavement, where they could be damaged by 

snow plow operations, rather than recessed. Figure 7 shows an 

example of raised rumble strips. 

Agencies should be sure to have inspectors present during 

installation to ensure the devices used are spaced appropriately 

and located per the plans either within the pavement markings 

or at the appropriate offset. It is also critical that the devices 

adhere properly to the pavement so they do not become 

projectiles when vehicle tires cross them. 

FIGURE 6. Poor Results Due to Differing Cross Slopes

Photo: FHWA

FIGURE 7. Example of Raised Rumble Strips

Photo: Alpine Products, Inc.
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

Rumble Strip Maintenance

All rumble strips are essentially “self-cleaning,” as snow, ice, 

rain, or sand do not typically remain for any length of time; 

this is attributed to the wind created by passing vehicles. 

Milled rumble strips typically require little to no maintenance.8

Missouri, South Carolina, Pennsylvania, and Washington DOTs 

all reported no use of preventative maintenance treatments 

on their rumble strips. According to a technical advisory from 

FHWA in 2011, asphalt fog seals can be used over milled-in 

rumble strips where there are deterioration concerns, as shown 

in Figure 8. The purpose of fog sealing rumble strips is to reduce 

oxidation and moisture penetration into the pavement.9

Although fog seals have been commonly used over rumble 

strips in the past, many States have discontinued using them 

due to a lack of documented findings that prove added value 

to pavement life. South Carolina DOT also reports that fog 

seals proved to be incompatible with thermoplastic pavement 

markings.10 Similarly, Missouri DOT reported that the fog seal 

was unnecessary when installing rumble stripes because the 

rumble strip is sealed by the pavement marking paint.11 Keep 

in mind that raised rumble strips do require maintenance, 

particularly those that include raised pavement markers that 

can become loose over time. 

8 E.R. Russel and M.J. Rys, NCHRP Synthesis 339: Centerline Rumble Strips – A Synthesis of Highway 

Practices, Transportation Research Board, National Cooperative Highway Research Program 

(Washington, DC: TRB 2005).

9 FHWA, “Technical Advisory T 5040.39: Shoulder and Edge Line Rumble Strips,” Revision 1, 

November 7, 2011. Available at: http://safety.fhwa.dot.gov/roadway_dept/pavement/rumble_

strips/t504039/

10 Interview with Mark Hunter, David Rogers, Andy Johnson, Brett Harrelson, Joey Riddle, Rob 

Bedenbavgh, and David Cook, South Carolina DOT, conducted on January 23, 2013.

11 Interview with John Miller, Joe Jones, Ashley Reinkemeyer, Michael Curtit, and John Donahue, 

Missouri DOT, conducted on June 5-6, 2013.

Maintaining Rumble Strips during 

Pavement Maintenance

Several agencies have specific considerations and experiences 

related to maintaining existing rumble strips during pavement 

overlays and chip seal applications. Some agencies re-install 

the rumble strips immediately, as part of the resurfacing project, 

while others choose to re-install them during area-wide rumble 

strip installation projects, which are scheduled at intervals 

(such as annually) to replace rumble strips on all recently 

paved projects. 

Surface preparation when paving over existing rumble strips 

also varies. Some agencies have found that simply overlaying 

the rumble strip works adequately, while others mill out the 

rumble strips and either inlay or overlay. Many agencies mill 

the pavement before placing the new asphalt overlay – the 

rumble strip is removed by this standard milling process, thus 

the situation of treating existing rumble strips is not experienced 

in many new asphalt overlays.

FIGURE 8. Fog Seal Application

Photo: Surface Preparation Technologies, LLC
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

Chip seals on top of existing rumble strips have been shown 

to retain the basic shape of the rumble, although some crosssection may be lost. As mentioned previously, it is not advisable 

to mill in rumble strips after chip sealing as agencies have in 

many cases observed delamination of the chip seal in the area 

surrounding the rumble.

While micro-surfacing fills in existing lines of rumble strips, a 

fresh line of rumble strips can be cut into the overlay at the 

same location without significant delamination occurring. 

Michigan DOT requires that, prior to applying the top course 

of micro-surface, pavement be cleaned and existing rumble 

strips filled either by a leveling course or a separate pass.

Summary

Center line and edge line rumble strips are very effective 

in reducing crashes. Rumble strips can be milled into new 

pavement or retrofitted on existing pavements. In areas without 

snow plowing, raised rumble strips are sometimes used. Many 

agencies that have retrofitted milled rumble strips into a 

significant portion of their existing two-lane highway system 

have found only isolated incidences of pavement deterioration. 

Other agencies typically only place rumble strips on pavement 

that is less than 5 years old. If the age, condition, type, or 

thickness of the pavement is a concern, modified rumble strip 

dimensions may be appropriate. Knowledge of how to address 

rumble strips with preventive maintenance treatments is sparse 

but growing. 

Where problems were found milling across joints, pavement 

experts have typically concluded that joints were in poor 

condition, and construction techniques for joints require 

improvement. Where concerns about milling into joints exist, 

alternative rumble strip designs may avoid milling across the 

joint. Inspecting rumble strips is simple but necessary to ensure 

this safety countermeasure performs as designed. Virtually no 

maintenance is required for rumble strips until the pavement is 

overlaid or reconstructed. 
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS

Where to Learn More

The following resources provide more details related to rumble strip use and design:

 NCHRP Report 641: Guidance for the Design and Application of Shoulder and Centerline Rumble Strips. 

http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_641.pdf

 NCHRP Synthesis 339: Center Line Rumble Strip – A Synthesis of Highway Practices.

http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_syn_339.pdf

 FHWA’s Rumble Strip Website: http://safety.fhwa.dot.gov/roadway_dept/pavement/rumble_strips/

FHWA, Office of Safety: 

Cathy Satterfield

cathy.satterfield@dot.gov

(708) 283-3552

FHWA Resource Center: 

Andy Mergenmeier

Andy.Mergenmeier@dot.gov

(410) 962-0091
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RUMBLE STRIP IMPLEMENTATION GUIDE | ADDRESSING PAVEMENT ISSUES ON TWO-LANE ROADS
14 FHWA-SA-15-034

APRIL 2015

For more information on

Rumble Strip Implementation Guide: 

Addressing Pavement Issues on Two-Lane Roads, visit:

FHWA Office of Safety

http://safety.fhwa.dot.gov/