U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590

Skip to content
Facebook iconYouTube iconTwitter iconFlickr iconLinkedInInstagram

Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations

This report is an archived publication and may contain dated technical, contact, and link information
Back to Publication List        
Publication Number:  FHWA-HRT-17-098     Date:  January 2018
Publication Number: FHWA-HRT-17-098
Date: January 2018


Self-Enforcing Roadways: A Guidance Report

PDF Version (4.05 MB)

PDF files can be viewed with the Acrobat® Reader®


Each year, more than 13,000 people are killed in speeding-related crashes. The majority of speeding-related crashes occur on roads that are not part of the interstate system. Local streets and collector roads have the highest speeding-related fatality rate on the basis of miles driven per vehicle. A self-enforcing road (sometimes referred to as a “self-explaining roadway”) is a roadway that is planned and designed to encourage drivers to select operating speeds in harmony with the posted speed limit. Properly designed self-enforcing roadways can be effective in producing speed compliance and may contribute to less severe crash outcomes.

The purpose of this report is to provide guidance on how to produce self-enforcing roadways. The concepts can be applied to planned and existing roadways. This report should be useful to transportation professionals, State departments of transportation, and researchers interested in designing and/or retrofitting roadways to induce drivers to drive at more appropriate speeds.

Monique R. Evans, P.E.
Director, Office of Safety
Research and Development


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 Government, industry, and the 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.

Technical report Documentation Page
1. Report No.
2. Government Accession No. 3. Recipients Catalog No.
4. Title and Subtitle
Self-Enforcing Roadways: A Guidance Report
5. Report Date
January 2018
6. Performing Organization Code
7. Author(s)
Eric Donnell, Kristin Kersavage, and Lisa Fontana Tierney
8. Performing Organization Report No.
9. Performing Organization Name and Address
Institute of Transportation Engineers
1627 Eye Street NW, Suite 600
Washington, DC 20006

Penn State University
212 Sackett Building
University Park, PA 16802
10. Work Unit No.
11. Contract or Grant No.
12. Sponsoring Agency Name and Address
U.S. Department of Transportation
Federal Highway Administration
Turner-Fairbank Highway Research Center
6300 Georgetown Pike
McLean, VA 22101
13. Type of Report and Period Covered
Final Report; July 2015-November 2017
14. Sponsoring Agency Code:
15. Supplementary Notes
The Task Order Manager for this report is Abdul Zineddin (HRDS-10).
16. Abstract
The objective of this project was to develop a guidance report to identify methods that may produce self-enforcing, or self-explaining, roadways during the geometric design process. While safety performance associated with these methods is not well understood yet, an implied outcome of effective speed management is that less severe crashes will result via the application of self-enforcing, or self-explaining, road design principles. Six self-enforcing road concepts and the processes needed to implement the concepts when designing or evaluating existing two-lane rural highways are identified and described in this document. It is anticipated that the concepts may be used to design roadways that produce operating speeds consistent with the desired operating speeds of the roadway. The six methods include: (1) the speed feedback loop process, (2) the inferred design speed approach, (3) design consistency methods, (4) applying geometric design criteria, (5) using a combination of signs and pavement markings, and (6) setting rational speed limits.
17. Key Words
Self-enforcing road, self-explaining road, two-lane rural highway, operating speed, speed limit, design speed, speed management, safety
18. Distribution Statement
No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161.http://www.ntis.gov
19. Security Classif. (of this report)
20. Security Classif. (of this page)
21. No. of Pages:
22. Price

Form DOT F 1700.7 (8-72) Reproduction of completed pages authorized.

SI* (Modern Metric) Conversion Factors

Table of Contents

List of Figures

List of Tables

List of Abbreviations

AADT annual average daily traffic (vehicles per day)
AASHTO American Association of State Highway and Transportation Officials
DCM Design Consistency Module
EB empirical Bayes
FHWA Federal Highway Administration
HSM Highway Safety Manual
HSO horizontal sight line offset
IHSDM Interactive Highway Safety Design Model
ITE Institute of Transportation Engineers
MUTCD Manual on Uniform Traffic Control Devices
NHTSA National Highway Traffic Safety Administration
OLS ordinary least squares
SHRP2 Second Strategic Highway Research Program
SSD stopping sight distance
TAC Transportation Association of Canada
TRB Transportation Research Board
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000
Turner-Fairbank Highway Research Center | 6300 Georgetown Pike | McLean, VA | 22101