PAVEMENT MARKING ARROWS

Description

Painted arrows on freeway exit ramps and in through lanes near 

intersections on divided highways can be used as a countermeasure for 

WW movements. In locations where crossroad channelization and ramp/

intersection geometry make WW movements easy, a WW arrow can be 

placed in each lane of an exit ramp near the crossroad terminal or in each 

through lane near the intersection on a divided highway, where it will be 

clearly visible to a potential WW movement driver.

Compendium of 

Wrong-Way-Driving 

Treatments and 

Countermeasures

FHWA Publication No.: FHWA-HRT-23-035

FHWA Contact: Carol H. Tan, Ph.D. 

(ORCID: 0000-0002-0549-9782), HRSO-20, 

Team Leader, Safety Data and Analysis Team, 

(202) 493-3315, carol.tan@dot.gov

This document is a compendium for Developing 

Crash Modification Factors for Wrong-Way-Driving 

Countermeasures (FHWA-HRT-22-115).

INTRODUCTION

Wrong-way-driving (WWD) events have the potential to result in severe 

crashes, as well as injuries and fatalities. Thus, even though such events 

are relatively rare, information on potential countermeasures to reduce 

the occurrence of such events is valuable for road agencies to promote 

safety on their roadway networks. Multiple past efforts have documented 

implementation and testing of various strategies and devices to reduce 

wrong-way (WW) movements. 

This document summarizes a selection of treatments that were of greatest 

interest to State departments of transportation (DOT) staff members and 

other practitioners who attended the Federal Highway Administration 

(FHWA) Workshop: Wrong-Way-Driving Safety Improvements (see link 

in Additional Resources). This compendium provides a brief description 

of each treatment, along with potential applications and considerations for 

use, reported effectiveness—including Crash Modification Factors (CMFs)

where available, and references to resources for more detailed information 

on guidance and completed studies.

More details and an extended list of related countermeasures can be found 

in the resources provided with each countermeasure herein presented.

COMPENDIUM

Research, Development, 

and Technology

Turner-Fairbank Highway 

Research Center

6300 Georgetown Pike

McLean, VA 22101-2296

https://highways.dot.gov/research
2

Key Advantages

• Provide additional feedback to a driver within 

the primary field of view.

• Are a relatively low-cost treatment that can be 

provided in combination with other treatments.

Features

Applications of this treatment have the following features:

• Provide additional feedback to driver within the 

primary field of view.

• Are a relatively low-cost treatment that can be 

provided in combination with other treatments.

• Can lead to increased maintenance because painted 

markings typically have short lifespans.

Effectiveness

Painted arrows have been used extensively on roadways 

with recognizable results(Finley et al. 2014). Applications 

on freeway ramps have shown WW or lane-use arrows 

contribute to reduced WW crashes in both daytime and 

nighttime conditions (Finley et al. 2018). The presence 

of WW arrows on divided highways is associated with 

a reduction in the risk of WW crashes, particularly 

nighttime WW crashes (Finley et al. 2018).

Safety Benefits/Crash Modification Factors

The following benefits are expected:

• For daytime crashes at freeway ramps: CMF = 0.189 

(from Evaluations of Low-Cost Safety Improvements 

Pooled Fund Study (ELCSI-PFS) Phase XI Evaluation) 

(Avelar, Kutela, and Finley. 2023).

• For nighttime crashes at freeway ramps: CMF = 0.227 

(from ELCSI-PFS Phase XI Evaluation) (Avelar, 

Kutela, and Finley. 2023).

Illustration. Wrong-way arrow pavement marking 

(MUTCD Figure 3B-24.D (FHWA 2012)).

Source: FHWA.

REFERENCES/LINKS

Avelar, R., B. Kutela, and M. Finley. 2023.

Developing Crash Modification Factors for 

Wrong-Way-Driving Countermeasures. Report 

No. FHWA-HRT-22-115. Washington, DC: 

Federal Highway Administration.

FHWA. 2012. “Wrong-Way Traffic Control at 

Interchange Ramps,” in Manual on Uniform 

Traffic Control Devices for Streets and 

Highways, 2009 Edition. Washington, DC: 

Federal Highway Administration, p 83 

(Figure 2B-18) and p. 388 (Figure 3B-24). 

https://mutcd.fhwa.dot.gov/kno_2009r1r2.htm, 

last accessed September 20, 2022.

Finley, M. D., R. E. Avelar, S. P. Venglar, G. H. 

Hawkins, and H. Al-Deek. 2018. Traffic 

Control Devices and Measures for Deterring 

Wrong-Way Movements. NCHRP Report No. 881. 

Washington, DC: Transportation Research Board. 

https://www.trb.org/Publications/Blurbs/178000.

aspx, last accessed September 20, 2022.

Finley, M. D., S. P. Venglar, V. Iragayarapu, J. D. Miles, 

E. S. Park, S. A. Cooner, and S. E. Ranft. 2014. 

Assessment of the Effectiveness of Wrong Way 

Driving Countermeasures and Mitigation Methods. 

Report No. FHWA/TX-15/0-6769-1. Austin, TX: 

Texas Department of Transportation. https://tti.

tamu.edu/documents/0-6769-1.pdf, last accessed 

September 20, 2022.

SUPPLEMENTAL SIGNS

Description

Additional DO NOT ENTER (DNE) and WW signs 

can be added to reinforce the message to WW drivers. 

The DNE and WW signs may be enhanced by using a 

larger sign instead of the standard size sign to increase 

sign visibility. Placards may also be used to provide 

additional information to drivers.

Key Advantages

• More noticeable due to more signs and 

larger size.

• Relatively low-cost treatment and can 

be combined with other treatments.
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Illustration. Example of application of regulatory signing and pavement markings at an exit ramp termination to deter 

WW entry (MUTCD Figure 2B-18 (FHWA 2012)).

Source: FHWA.

Features

Applications of this treatment have the following features:

• Are more noticeable due to the additional signs 

and plaques as well as increased visibility from 

size enhancement.

• Are a relatively low-cost treatment that can be 

provided in combination with other treatments.

• Have increased costs due to use of larger signs 

and/or use of more signs than standard design.

Effectiveness

Supplemental signs have been used in many States, with 

some installations prior to 2010 (Finley et al. 2014). 

Variations include rotating one or more additional signs 

or using a different mounting height to provide drivers 

with a different viewing angle (Finley et al. 2014). 

Studies indicate use is related to reduced crashes 

(Finley et al. 2018).

Safety Benefits/Crash Modification Factors

At exit ramps intersecting undivided cross streets 

(from ELCSI-PFS Phase XI Evaluation) (Avelar, 

Kutela, and Finley. 2023):

• For daytime crashes: CMF = 0.321 (DNE).

• For nighttime crashes: CMF = 0.640 (DNE) 

and 0.767 (WW).

REFERENCES/LINKS

Avelar, R., B. Kutela, and M. Finley. 2023. 

Developing Crash Modification Factors for 

Wrong-Way-Driving Countermeasures. Report 

No. FHWA-HRT-22-115. Washington, DC: 

Federal Highway Administration.

FHWA. 2012. “Wrong-Way Traffic Control at Interchange 

Ramps,” in Manual on Uniform Traffic Control 

Devices for Streets and Highways, 2009 

Edition. Washington, DC: Federal Highway 

Administration, p 76 (Figure 2B-41). https://

mutcd.fhwa.dot.gov/kno_2009r1r2.htm, last 

accessed September 20, 2022.

Finley, M. D., R. E. Avelar, S. P. Venglar, G. H. 

Hawkins, and H. Al-Deek. 2018. Traffic 

Control Devices and Measures for Deterring 

Wrong-Way Movements. NCHRP Report No. 881. 

Washington, DC: Transportation Research Board. 

https://www.trb.org/Publications/Blurbs/178000.

aspx, last accessed September 20, 2022.

Finley, M. D., S. P. Venglar, V. Iragayarapu, J. D. Miles, 

E. S. Park, S. A. Cooner, and S. E. Ranft. 2014. 

Assessment of the Effectiveness of Wrong Way 

Driving Countermeasures and Mitigation Methods. 

Report No. FHWA/TX-15/0-6769-1. Austin, TX: 

Texas Department of Transportation. https://tti.

tamu.edu/documents/0-6769-1.pdf, last accessed 

September 20, 2022.
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BLANK-OUT SIGNS

Description

Blank-out WW signs can be added to attract the 

attention of WW drivers. These signs display the same 

messages as the standard MUTCD R5-1a sign but are 

activated only when a WWD event is detected.

Key Advantages

• Active only when event occurs.

• Can be used on ramps and main lanes.

Illustration. WRONG WAY sign (MUTCD Figure 2B-11 

R5-1a (FHWA 2012a)).

Source: FHWA.

Features

Applications of this treatment have the following features:

• May be more successful with active signing 

message than passive signing or lighted passive 

signing in attracting WW drivers’ attention.

• Are appropriate for exit ramps or the main lanes 

of a highway or freeway.

• Are currently an experimental application.

• Can be expensive to install at multiple locations.

• Have effectiveness that is related to performance 

of the detector system.

Effectiveness

Active roadway signing may be more successful than 

passive signing in capturing driver attention in some 

situations. The treatment requires a system of sensors to 

detect WW vehicles and activate the signs. Because the 

treatment is experimental, deployment and testing are 

limited and studies documenting specific influences on 

crashes are rare (Finley et al. 2014). However, anecdotal 

evidence suggests that the activated signs are useful in 

alerting WW drivers (FHWA 2012b).

Safety Benefits/Crash Modification Factors

The expected benefits include anecdotal reductions in 

WWD events.

REFERENCES/LINKS

FHWA. 2012a. “Regulatory Signs, Barricades, and 

Gates,” in Manual on Uniform Traffic Control 

Devices for Streets and Highways, 2009 

Edition. Washington, DC: Federal Highway 

Administration, p 75 (Figure 2B-11 R5-1a). 

https://mutcd.fhwa.dot.gov/kno_2009r1r2.htm, 

last accessed September 20, 2022.

FHWA. 2012b. “Changeable Message Signs,” in 

Manual on Uniform Traffic Control Devices for 

Streets and Highways, 2009 Edition. Washington, 

DC: Federal Highway Administration, p 325. 

https://mutcd.fhwa.dot.gov/kno_2009r1r2.htm, 

last accessed September 20, 2022.

Finley, M. D., S. P. Venglar, V. Iragayarapu, J. D. Miles, 

E. S. Park, S. A. Cooner, and S. E. Ranft. 2014. 

Assessment of the Effectiveness of Wrong Way 

Driving Countermeasures and Mitigation 

Methods. Report No. FHWA/TX-15/0-6769-1. 

Austin, TX: Texas Department of Transportation. 

https://tti.tamu.edu/documents/0-6769-1.pdf, 

last accessed September 20, 2022.

Key Advantages

• Improved visibility at night.

• Active only during detected events.

SIGNS WITH FLASHING 

ENHANCEMENTS

Description

Standard MUTCD R5-1a WRONG WAY signs can be 

enhanced with treatments such as flashing beacons or 

light emitting diode (LED) borders to improve nighttime

visibility for WW drivers (FHWA 2012a, 2012b; Finley 

et al. 2014). The lights are activated only when a WWD 

event is detected.
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Illustration. WRONG WAY sign (MUTCD Figure 

2B-11 R5-1a) with circular rapid flashing beacon 

and wrong-way-driving detection system.

© 2020 Connecticut Department of Transportation.

Features

Applications of this treatment have the following features:

• Are more noticeable at night due to increased 

visibility from enhancement.

• Are appropriate for exit ramps or the main lanes 

of a highway or freeway.

• Are currently an experimental application.

• Require a power source, which could be solar.

• Have a detector system whose effectiveness is 

related to performance of the system.

Effectiveness

Because the flashing treatments are active only when an 

event is detected, the beacons or LEDs are better able to 

attract WW drivers’ attention, particularly at night. The 

performance of the treatment relies on sensors to detect 

WW vehicles and activate the signs. These treatments 

are experimental and not widely deployed. However, 

where sufficient data are available, results suggest that 

the enhancements are useful in alerting WW drivers.

Safety Benefits/Crash Modification Factors

The following benefits are expected:

• Data show a 60-percent reduction in reported events 

for ramps with LED border signs (California) 

(Bucko 2020).

• Data show an 88-percent self-correction of WW 

drivers for ramps with LED border signs (Arizona) 

(Anderson and Lovell 2022).

REFERENCES/LINKS

Anderson, S., and J. Lovell. 2022. “ADOT’s Wrong Way 

Vehicle Detection Program.” Presented at the 

FHWA Wrong Way Driving Workshop. Phoenix, 

AZ: Arizona Department of Transportation. 

https://static.tti.tamu.edu/conferences/wwd22/

presentations/day1/7-anderson-lovell.pdf, last 

accessed September 20, 2022.

Bucko, T. R. 2020. Wrong Way Pilot Projects for 

Prevention of Wrong Way Collisions on Freeways. 

Sacramento, CA: California Department of 

Transportation, Division of Traffic Operations. 

https://dot.ca.gov/-/media/dot-media/programs/

safety-programs/documents/wrong-way/wwpilot-projects-for-prevention-of-ww-collisions-onfreeways-a11y.pdf, last accessed August 9, 2022.

FHWA. 2012a. “Regulatory Signs, Barricades, and Gates,” 

in Manual on Uniform Traffic Control 

Devices for Streets and Highways, 2009 

Edition. Washington, DC: Federal Highway 

Administration, p 75 (Figure 2B-11 R5-1a). 

https://mutcd.fhwa.dot.gov/kno_2009r1r2.htm, 

last accessed September 20, 2022.

FHWA. 2012b. “Enhanced Conspicuity for Standard 

Signs,” in Manual on Uniform Traffic Control 

Devices for Streets and Highways, 2009 

Edition. Washington, DC: Federal Highway 

Administration, Section 2A.15, p 36. https://

mutcd.fhwa.dot.gov/kno_2009r1r2.htm, last 

accessed September 20, 2022.

Finley, M. D., S. P. Venglar, V. Iragayarapu, J. D. 

Miles, E. S. Park, S. A. Cooner, and S. E. Ranft. 

2014. Assessment of the Effectiveness of Wrong 

Way Driving Countermeasures and Mitigation 

Methods. Report No. FHWA/TX-15/0-6769-1. 

Austin, TX: Texas Department of Transportation. 

https://tti.tamu.edu/documents/0-6769-1.pdf, 

last accessed September 20, 2022.
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GEOMETRIC 

IMPROVEMENTS

Description

A ramp or crossroad that is difficult to physically

enter from the wrong direction will provide an 

inherent improvement for reducing wrong-way 

events and crashes. The geometric design of an 

access point can be tailored to conditions to provide 

improved separation between opposing directions 

of traffic, physical restrictions on prohibited turning 

movements, and more intuitive driving paths for 

desired movements (AASHTO 2019; National 

Academy of Sciences 2022).

Key Advantages

• Physical restriction on WW movements.

• Facilitation of correct movements.

Illustration. Example of application of geometric 

treatments to deter WW movements around exit ramps.

© 2022 Texas A&M Transportation Institute.

EB = eastbound; WB = westbound.

Features

Applications of this treatment have the following features:

• Provide or increase separation between adjacent 

entrance and exit ramps (or other pairs of 

access points).

• Are recommended to be used with raised medians 

to prevent selected turning movements (Finley 

et al. 2018).

• Are recommended to be used with painted or 

raised channelizing islands to guide drivers into 

desired paths and away from prohibited paths 

(Finley et al. 2014).

• Decrease radii of potential entry paths to 

discourage WW turning.

• Can be costly, depending on treatment and 

available right-of-way.

Effectiveness

Numerous ramp and intersection designs can be found 

across the country, many of them implemented to meet 

specific needs of a given intersection or interchange 

(AASHTO 2019). Anecdotal and formal studies indicate 

tailoring the geometric design to site conditions has 

the potential for success in reducing WW events and 

crashes (Finley et al. 2014, 2018).

Safety Benefits/Crash Modification Factors

The following benefits are expected:

• Remove driveway from frontage: CMF = 0.873 

(daytime crashes from ELCSI-PFS Phase XI 

Evaluation) (Avelar, Kutela, and Finley. 2023).

• Add 100 ft to exit ramp: CMF = 0.972 (nighttime 

crashes from ELCSI-PFS Phase XI Evaluation) 

(Avelar, Kutela, and Finley. 2023).

REFERENCES/LINKS

American Association of State Highway and 

Transportation Officials (AASHTO). 2019. 

A Policy on Geometric Design of Highways 

and Streets. Washington, DC: AASHTO. 

(Also known as the Green Book.)

Avelar, R., B. Kutela, and M. Finley. 2023. 

Developing Crash Modification Factors for

Wrong-Way-Driving Countermeasures. Report 

No. FHWA-HRT-22-115. Washington, DC: 

Federal Highway Administration.
7

Finley, M. D., R. E. Avelar, S. P. Venglar, G. H. Hawkins, 

and H. Al-Deek. 2018. Traffic Control Devices 

and Measures for Deterring Wrong-Way 

Movements. NCHRP Report 881. Washington, 

DC: Transportation Research Board. https://www.

trb.org/Publications/Blurbs/178000.aspx, last 

accessed September 20, 2022.

Finley, M. D., S. P. Venglar, V. Iragayarapu, J. D. 

Miles, E. S. Park, S. A. Cooner, and S. E. Ranft. 

2014. Assessment of the Effectiveness of Wrong 

Way Driving Countermeasures and Mitigation 

Methods. Report No. FHWA/TX-15/0-6769-1. 

Austin, TX: Texas Department of Transportation. 

https://tti.tamu.edu/documents/0-6769-1.pdf, 

last accessed September 20, 2022.

National Academy of Sciences. 2022. “NCHRP 

Project 3-135: Wrong-Way Driving Solutions, 

Policy, and Guidance” (web page). Washington, 

DC: Transportation Research Board. https://

apps.trb.org/cmsfeed/TRBNetProject

Display.asp?ProjectID=4548, last accessed 

August 10, 2022.

DETECTOR SYSTEMS

Description

A detector system forms the backbone of an active 

treatment strategy that involves more than static signs 

and pavement markings. Even though such a system can

be costly, many potential uses exist for a system that 

accurately detects and sends notifications of WWD events.

Key Advantages

• Necessary component for driver and 

agency alerts.

• Potential for expanded use with new 

technologies.

Illustration. Example of application of a WW detector 

system installation on a freeway exit ramp that 

intersects a one-way frontage road.

© 2022 Texas A&M Transportation Institute.

EB = eastbound; WB = westbound.

Features

Applications of this treatment have the following features:

• Provide the necessary component for activating a 

treatment for a WW driver and for sending alerts 

to law enforcement and transportation agencies.

• Are a potential source of data to study and document 

WWD events and effectiveness of countermeasures 

(Golias, Mishra, and Ngo 2021).

• Have the possibility of providing notifications 

through new technologies such as in-vehicle alerts 

for connected and automated vehicles.

• Require purchasing detectors and supporting 

hardware, which provides power and connects the 

system to desired treatments and agencies.

• Require constant maintenance to retain performance.

Effectiveness

A detector system with the appropriate hardware and 

functioning communication supplies the information 

necessary for active treatments to perform their intended 

functions (Finley et al. 2014). A variety of systems 

are available. An agency using such a system must 

define its intended use and develop specifications for 

procurement, in addition to maintaining that system 

in the long term (Simpson 2013).
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Researchers—This study was performed under contract number DTFH6116D00039L by Raul Avelar (principal 

investigator) and researchers Boniphace Kutela and Melisa Finley of the Texas A&M Transportation Institute.

Distribution—This Compendium is being distributed according to a standard distribution. Direct distribution is 

being made to the FHWA divisions and Resource Center.

Availability—This Compendium may be obtained at https://highways.dot.gov/research.

Key Words—Crash modification factor, CMF, wrong-way driving, safety.

Notice—This document is disseminated under the sponsorship of the U.S. Department of Transportation (USDOT) in 

the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained 

in this document. The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ 

names appear in this report only because they are considered essential to the objective of the document.

Quality Assurance Statement—The Federal Highway Administration (FHWA) provides high quality information to 

serve the Government, industry, and public in a manner that promotes public understanding. Standards and policies 

are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically 

reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.

FEBRUARY 2024 FHWA-HRT-23-035

HRSO-20/02-24(WEB)E

Recommended citation: Federal Highway Administration, 

Compendium of Wrong-Way-Driving Treatments and Countermeasures 

(Washington, DC: 2024) https://doi.org/10.21949/1521979

Safety Benefits/Crash Modification Factors

The following benefits are expected:

• Serves as the starting point for a response system 

to activate treatments.

• Notifies law enforcement (Simpson 2013).

• Provides alerts to drivers.

REFERENCES/LINKS

Finley, M. D., S. P. Venglar, V. Iragayarapu, J. D. 

Miles, E. S. Park, S. A. Cooner, and S. E. Ranft. 

2014. Assessment of the Effectiveness of Wrong 

Way Driving Countermeasures and Mitigation 

Methods. Report No. FHWA/TX-15/0-6769-1. 

Austin, TX: Texas Department of Transportation. 

https://tti.tamu.edu/documents/0-6769-1.pdf, 

last accessed September 20, 2022.

Golias, M., S. Mishra, and H. Ngo. 2021. Investigation 

on Wrong Way Prevention Technologies and 

Systems. Report No. RES2020-02. Nashville, TN: 

Tennessee Department of Transportation. https://

www.tn.gov/content/dam/tn/tdot/long-rangeplanning/research/final-reports/res2020-finalreports/RES2020_02_Final_Report_Approved.

pdf, last accessed September 20, 2022.

Simpson, S. A. 2013. Wrong-way Vehicle Detection: 

Proof of Concept. Report No. FHWA-AZ-13-697. 

Phoenix, AZ: Arizona Department of 

Transportation. https://rosap.ntl.bts.gov/view/

dot/25869, last accessed September 20, 2022.

ADDITIONAL RESOURCES

A number of resources were provided with the 

descriptions of the countermeasures listed in this 

document. A more complete list of resources, 

including those found in this document, can be 

found in those shared through presentations and 

links provided by speakers and attendees at the 

Federal Highway Administration Workshop: 

Wrong-Way Driving Safety Improvements held 

March 9–10, 2022.

The program, presentations, and resources from 

the Federal Highway Administration Workshop: 

Wrong-Way Driving Safety Improvements can be 

found here: https://events.tti.tamu.edu/conference/

the-federal-highway-administration-workshopwrong-way-driving-safety-improvements/program/.

The presentations and resources provided on the 

workshop website are included as they were shared 

during the workshop and are provided as additional 

information. Questions about these resources should 

be directed to the author, agency, or company that 

produced them.