Integrating Speed Management within Roadway Departure, Intersections, and Pedestrian and Bicyclist Safety Focus Areas

Program Contact

Guan Xu
Guan.Xu@dot.gov
(202) 366-5892

Chapter 4. Integrating Speed Management within the Three Safety Focus Areas

With roadway departure, intersections, and pedestrian and bicycle crashes accounting for approximately 90 percent of the traffic fatalities in the United States, these key focus areas are a vital link in managing speed and targeting speeding-related crashes.¹⁴ Using the results of this research project's crash analysis report,¹⁵ this chapter includes crash trends involving speeding-related fatal crashes and potential strategies to assist agencies in addressing speeding-related crashes within each focus area. While each focus area and its respective strategies are listed in separate sections within Chapter 4, FHWA encourages agencies to use a combination of strategies since speeding-related crash issues often overlap into multiple focus areas. Overall program-level strategies (non-focus area specific) are listed in Chapter 3.

4.1 Roadway Departure and Speed Management

A roadway departure crash is defined by FHWA as "a crash which occurs after a vehicle crosses an edge line or a center line, or otherwise leaves the traveled way."¹⁶

Roadway departure crashes are frequently severe and account for the majority of highway fatalities. In 2013, there were 18,257 fatalities as a result of roadway departure crashes, which accounted for 56 percent of the traffic fatalities in the United States.¹⁷ Approximately 40 percent of fatal roadway departure crashes are speeding-related.¹⁸

4.1.1 National Crash Data Analysis Trends

Crash analysis performed on national data relating to speeding-related and roadway departure crashes gives insight into the nature of these crash types, where these crashes occur, and driver characteristics or behavioral elements that may affect the number and severity of these crashes.

The FHWA Safety Roadway Departure Program analyzed Fatality Analysis Reporting System (FARS) and General Estimation System (GES) data (2010-2013) and determined there are three primary event types that are most harmful in 75 percent of all roadway departure crashes:

Overturn/rollover crashes
Opposing direction crashes
Crashes involving trees.

Bar graph depicts the percentage of roadway departure crash fatalities and serious injuries broken out by crash type: overturns and rollovers accounted for 28 percent of roadway departure fatalites and 27 percent of serious injuries. Opposing direction crashes accounted for 25 percent of roadway departure fatalities and 17 percent of serious injuries. Crashes involving trees accounted for 19 percent of roadway departure fatalities and 15 percent of serious injuries.

Figure 4 – Percent of Roadway Departure Fatalities and Serious Injuries by Crash Type (FARS and GES 2010-2013)

These top three crash types have been designated as primary emphasis areas and researchers determined speed is one of the contributing factors. Each crash category underwent further analysis to determine where these crashes occur and significant contributing factors. Figures 5 through 7 show the results.

Bar graph shows that critical locations for rollover overurn roadway departure crashes include rural areas (account for 76 percent of crashes), areas with a posted speed greater than or equal to 50 mph (72 percent), and curves (43 percent).

Figure 5 – Critical Locations for Rollover/Overturn Roadway Departure Crashes (Source: FARS 2010-2013)

Bar graph shows that critical locations for opposing direction roadway departure crashes include undivided roads (accounting for 83 percent of roadway departure crashes), rural areas (70 percent), areas where the posted speed is greater than or equal to 50 mph (70 percent), curves (31 percent), and adverse weather conditions (wet or icy) (23 percent).

Figure 6 – Critical Locations for Opposing Direction Roadway Departure Crashes (Source: FARS 2010-2013)

Bar graph shows that, of allroadway departure crashes involving trees, 67 percent occur in rural areas, 33 percent occur in urban areas, 51 percent occur in areas where the posted speed is greater than or equal to 50 mph, 49 percent occur in areas where the posted speed is less than or equal to 45 mph, and and 46 percent occur on curves.

Figure 7 – Critical Locations for Roadway Departure Crashes Involving Trees (Source: FARS 2010-2013)

While the data above focuses more broadly on roadway departure crashes (not necessarily speeding- related), the following sections present some crash trends for speeding-related roadway departure crashes.

ROADWAY FUNCTIONAL CLASS

Initially, some may be surprised to learn that the majority of fatal speeding-related roadway departure crashes do not happen on Interstates and freeways. In fact, 85 percent of vehicles involved in these fatal crash types were traveling on local, collector, minor arterial, or other principal arterial roadways, as shown in Figure 8.

Pie chart depicts the distribution of vehicles involved in speeding related fatal roadway departure crashes on local roads, 27.2 percent; collectors, 25.1 percent; minor arterial, 16.7 percent; other principal arterials, 16 percent; freeways or expressways, 3.2 percent; interstates, 10.4 percent; and unknown: 1.5 percent.

Figure 8 – Distribution of Vehicles Involved in Speeding-related Fatal Roadway Departure Crashes by Type of Roadway
(Source: FARS 2010-2012)

The following figure shows the percentage of vehicles involved in these types of crashes that were speeding and non-speeding by roadway type during the 2010-2012 period. Nearly half of all vehicles involved in fatal roadway departure crashes on local roads are speeding-related. Other principal arterials and interstates ranked lowest at 32.4 percent and 33.8 percent, respectively.

Bar graph shows the percentage of vehicles involved in speeding-related fatal roadway departure by roadway type, including: local, 49.4 percent; collector, 40.8 percent; minor arterial, 37.3 percent; other principal arterial, 32.4 percent; freeway or expresway, 40.8 percent, and interstate, 33.8 percent.

Figure 9 – Percentage of Vehicles Involved in Speeding-related Fatal Roadway Departure Crashes by Type of Roadway
(Source: FARS 2010-2012)

POSTED SPEED LIMIT

The distribution of vehicles involved in speeding-related roadway departure fatal crashes by speed limit during the 2010-2012 period is shown in Figure 10. More than half of the vehicles involved in speeding-related roadway departure fatal crashes occur on roadways posted between 40 and 55 mph.

Vehicles traveling at 50 to 55 mph are involved in 34 percent of speeding-related raodway departure fatal crashes. Vehicles traveling 40 to 45 mph account for 21.4 percent of of speeding-related raodway departure fatal crashes. Vehicles traveling at 30 to 35 mph account for 18 percent of speeding-related raodway departure fatal crashes. Vehicles traveling at more than 60 mph acount for 17.3 percent of speeding-related raodway departure fatal crashes. Vehicles traveling at less than or equal to 25 mph account for 5.9 percent of roadway departure crashes, and 2.3 percent of fatal roadway departure crashes were traveling at an unknown speed.

Figure 10 – Distribution of Vehicles Involved in Speeding-related Roadway Departure Fatal Crashes by Speed Limit (MPH) of Corresponding Approach
(Source: FARS 2010-2012)

Figure 11 provides the percentage of vehicles involved in speeding and non-speeding roadway departure fatal crashes according to speed limit category. Note that the proportion of speeding-related crashes increases as the posted speed limit decreases.

Graph indicates that 53.75 percent of vehicles involved in speeding-related fatal roadway departure crashes were traveling on an approach that was less than or equal to 25 mph; 49.4 percent of such crashes occurred on roadways where the speed limit on the approach was 30 to 35 mph; 40.8 occurred on roadways where the speed limit on the approach was 40 to 45 mph; 32.4 percent occurred on roadways where the speed limit on the approach was 50 to 55 mph; and 29.4 percent occurred on roadways where the speed limit on the approach was greater than 60 mph.

Figure 11 – Percentage of Vehicles Involved in Speeding-related Fatal Roadway Departure Crashes by Speed Limit (MPH) of Corresponding Approach
(Source: FARS 2010 – 2012)

ROADWAY GEOMETRY

A major aspect of preventing speeding-related roadway departure crashes is addressing curves. As Figure 12 shows, a large share of speeding-related fatal roadway departure crashes occur on tangent sections of roadways. More than 37 percent of vehicles involved in speeding-related fatal roadway departure crashes are on curves.

The distribution of vehicles involved in speeding realated fatal roadway departure crashes by horizontal alignment is as follows: straight - 62.2 percent; curve right - 16.1 percent; urve left - 18 percent; curve (unknown direction) 3.7 percent.

Figure 12 – Distribution of Vehicles Involved in Speeding-related Fatal Roadway Departure Crashes by Horizontal Alignment (Source: FARS 2010-2012)

The percentage of vehicles involved in speeding related fatal roadway departure crashes by horizontal alignment is as follows: straight - 30.4 percent, curve - 47.3 percent.

Figure 13 – Percentage of Vehicles Involved in Speeding-related Fatal Roadway Departure Crashes by Horizontal Alignment
(Source: FARS 2010-2012)

When fatal roadway departure crashes are broken down separately by whether they occur on curves or straight sections of roadway, the likelihood of these types of crashes being speeding related is higher on curves. Close to half of vehicles involved in fatal roadway departure crashes on curves were coded as speeding related. By comparison, 30 percent of speeding-related fatal roadway departure crashes occurred on tangent sections of roadway.

DRIVER CHARACTERISTICS

The national data shows a very clear distinction: males are more likely to be involved in a roadway departure fatal crash and have even higher likelihood of being involved in a speeding-related roadway departure fatal crash. During the 2010-2012 period, males comprised approximately 75 percent of roadway departure fatalities and accounted for nearly 80 percent of speeding-related roadway departure fatalities. When looking at the fatal roadway departure crashes within each age group, both males and females in the 15 to 20 age group were more likely to be involved in speeding-related roadway departure crashes. As shown in Figure 14, 42.7 percent of fatal roadway departure crashes for females in the 15 to 20 age group were speeding-related while 52.6 percent of fatal roadway departure crashes for males in that age group were speeding-related.

Graph breaks out the percentage of drivers involved in speeding-related roadway departure fatalities by driver age and gender. Males between 15-20, 21-24, and 25-35 account for 52.6 percent, 51.8 percent, and 45.4 percent, respectively, of drivers involved in these types of fatal crashes. Males of all ages are involved in a greater percentage of these types of crashes than femails.

Figure 14 – Percentage of Drivers Involved in Speeding-related Roadway Departure Fatalities by Driver Age and Gender
(Source: FARS 2010-2012)

TIME OF DAY

With respect to the time of day, Figure 15 shows 60 percent of the speeding-related fatal roadway departure crashes happen between 6 p.m. and 5 a.m. Further analysis reveals that between midnight and 5 a.m., nearly 50 percent of all fatal roadway departure crashes that occur are speeding-related.

Speeding related roadway departure fatal crashes primarily occur during the 6 p.m. to midnight period (31 percent), followed by the midnight to 5 a.m. period (29.3 percent). The third most frequent period during which these crashes occur is 10 a.m. to 4 p.m. (18.3 percent), followed by the 4 to 6 p.m. period (8.9 percent), the 5 to 8 a.m. period (8.2 percent), and teh 6 to 10 a.m. period (4.4 percent).

Figure 15 – Distribution of Speeding-related Roadway Departure Fatal Crashes by Hour of Day
(Source: FARS 2010-2012)

4.1.2 Strategies

A number of potential strategies and countermeasures exist for agencies to consider when addressing speeding-related roadway departure crashes. By reviewing the national data, investigating the state of the practice, and conducting interviews with national experts, our researchers identified key issues relating to speeding-related roadway departure crashes. Some recommended strategies were identified through agency interviews and published resources.¹⁹ Every situation or location is unique, and agencies should exercise engineering judgment for determining the appropriate solution for their specific crash concerns.

Issue: National data shows 85 percent of vehicles involved in speeding-related roadway departure fatal crash types were traveling on local, collector, or minor arterial, or other principal arterial roadways.

Potential strategies:

Appropriate speed limits. Ensure speed limits are set appropriately by completing an engineering speed study and employing FHWA's USLIMITS2, a web-based tool to support and confirm speed limit setting decisions.²⁰
Speed limit review. Create a plan to review speed limits on these types of roadways systematically.
Data analysis. Analyze crash data to determine corridors where a large amount of speeding-related roadway departure crashes are occurring and provide this information to law enforcement and engineers in the jurisdiction.
Countermeasure Selection. Using the results of the data analysis and identifiable crash clusters, select appropriate speed management treatments using the speed management countermeasure reference materials available on FHWA's Speed Management website and other tools and resources listed in Appendix C.

Issue: Males are involved in nearly 80 percent of speeding-related roadway departure fatalities. Drivers ages 15 to 20 are more likely to be involved in speeding-related roadway departure fatal crashes.

Potential strategies:

Targeted educational campaigns. Create educational campaigns that target high-risk groups, such as males or all drivers in the 15 to 20 age group. These could include media outlets or venues such as high schools and universities, sporting events, clubs or extracurricular activities, and popular local hangouts.
Collaboration with partners. Collaborate with partners to improve driver education (e.g., schools, driver education programs, universities). Consider revisions for State driver education manuals.

Issue: Roadway departure fatalities within curves are more likely to be speeding-related.

Potential strategies:

Pavement markings. Pavement markings to consider are edge line striping for delineation or markings which create the illusion of traveling faster or narrowing lanes (e.g., converging chevron marking pattern, transverse markings, optical speed bars).
Rumble strips. Install centerline, edge line rumble strips, or both to provide audible and tactile notification to the driver if the vehicle departs the lane.
Standard curve signing. Ensure the appropriate curve signing is applied to meet MUTCD standards.
Enhanced signing. Apply enhanced signing and delineation (e.g., oversized signs, florescent sheeting, full post delineation, double-up signs).
Dynamic or ITS signs. Install dynamic chevrons, speed feedback signs,²¹ and speed activated warning or speed limit reminder signs. Variable speed limit signs may be beneficial in areas where inclement weather is common.
High friction surface treatment.²² Effective in addressing locations with friction or wet crash issues, high-friction surface treatments secure a thin layer of specially engineered, durable, high-friction aggregate as a topping on resins or polymers – usually urethane, silicon, or epoxy – with a binder. While this countermeasure does not reduce speeding vehicles, it provides long lasting skid resistance while also making the overlay much more resistant to wear and polishing, improving safety within curves.
Safety Edge_SM²³ or widening pavement. Installing Safety Edge_SM along roadways or widening pavement within curves may increase the likelihood of drivers to regain control of their vehicle if they drift out of their lane.

Issue: Rollover/overturn crashes, opposing direction crashes, and crashes involving trees are the three primary event types that are most harmful in 75 percent of all roadway departure crashes, and speeding is identified as one of the contributing factors.

Potential Strategies:

Data analysis. Analyze crash data to determine where these three types of crash types are occurring on the road system and either identify top corridors or use a systemic approach for choosing and implementing proven countermeasures.
Keep vehicles on the roadway and in their appropriate directional lane. Choose countermeasures that help keep vehicles on the roadway and in their lane, such as rumble strips or stripes, high-friction surface treatments, and high-visibility center and edge line striping.
Reduce potential for crashes and crash severity when vehicles do leave the roadway or their lane. Countermeasures that support this strategy include applying the Safety Edge_SM; widening the shoulder; removing, shielding, or delineating fixed objects; increasing the clear zone; and flattening slopes.

Speed management countermeasures references are available on FHWA's Speed Management website. FHWA has published two desktop references that summarize studies on the effectiveness of engineering countermeasures in reducing crashes and managing speed.²⁴ The CMF Clearinghouse provides a comprehensive database of CMFs along with supporting documentation to help agencies identify potential countermeasures and their proven levels of effectiveness.²⁵

4.2 Intersections and Speed Management

"An intersection, by design, is a planned location where vehicles traveling on different highways may come into conflict. The functional area of an intersection extends upstream and downstream from the physical area of the crossing streets. The different approach and crossing movements by motorists, bicyclists, and pedestrians make at-grade intersections one of the most complex traffic situations that people encounter."

Excerpt from FHWA Issue Brief 2, "The National Intersection Safety Problem," 2009

4.2.1 National Crash Data Analysis Trends

Intersections account for almost 20 percent of speeding-related fatal crashes and more than one-third of all speeding-related crashes. A summary of the national crash analysis results for speeding-related fatal crashes at intersections is shown below. The full analysis is included in Appendix A.

ROADWAY FUNCTIONAL CLASS

Figure 16 shows the distribution of vehicles involved in speeding-related fatal intersection crashes by roadway type during the 2010-2012 period. Nearly 53 percent took place on arterial roadways. Local roads contained more than 25 percent of the vehicles involved in speeding-related fatal intersection crashes.

Distribution of vehicles involved in speeding-related fatal instersection crashes by type of roadway is as follows: other principal arterial, 30.1 percent; local, 26.9 percent; minor arterial, 22.8 percent; collector, 15.8 percent; freeway/expressway, 2.2 percent; interstate, 1.1 percent; and unknown, 1.1 percent.

Figure 16 – Distribution of Vehicles Involved in Speeding-related Fatal Intersection Crashes by Type of Roadway
(Source: FARS 2010-2012)

POSTED SPEED LIMIT

The analysis by speed limit in Figure 17 shows that almost 60 percent of vehicles involved in speeding-related fatal intersection crashes from 2010 to 2012 happened on roadways with speed limits between 30 and 45 mph.

Distribution of vehicles involved in speeding-related fatal intersection crashes by speed limit (mph) of corresponding approach is as follows: 40 to 45, 30.1 percent; 30 to 35, 27.9 percent; 50 to 55, 20,3 percent; less than or equal to 25 mph, 11 percent; greater than 60, 5.4 percent; unknown, 5.2 percent.

Figure 17 – Distribution of Vehicles Involved in Speeding-related Fatal Intersection Crashes by Speed Limit (MPH) of Corresponding Approach
(Source: FARS 2010-2012)

DRIVER CHARACTERISTICS

Following the same trend as speeding-related fatal roadway departure crashes, male drivers account for more than 75 percent of speeding-related fatal crashes at intersections. When looking at the fatal intersection crashes within each age group, both males and females in the 21 to 24 age group were more likely to be involved in speeding-related intersection crashes. As shown in the figure below, 24.3 percent of female drivers and 35.6 percent of male drivers in that age group who were involved in fatal intersection crashes during the 2010-2012 period were speeding.

Data show that males of all ages are involved in a greater number of speeding-related fatal intersection crashes than females. The top three male age groups for this type of crash include those 21-24 years old at 35.6 percent; those 15-20 years at 31.6 percent, and those 25-34 at 29.4 percent. By comparison, females in these age groups involved in speeding-related fatal intersection crashes are 24.3 percent, 20.8 percent, and 19.4 percent, respectively.

Figure 18 – Percentage of Drivers by Age and Gender Involved in Speeding-related Fatal Intersection Crashes
(Source: FARS 2010-2012)

VEHICLE TYPE

The fact that passenger cars and light trucks account for approximately 75 percent of the vehicles involved in fatal intersection crashes is not surprising since they are the predominant transportation modes. With motorcycles making up just 3 percent of all registered vehicles in the United States and accounting for only 0.7 percent of all vehicle miles travelled,²⁶ the results in Figure 19, which shows that motorcycles account for over 17 percent of the vehicles that were involved in speeding-related fatal intersection crashes between 2010 and 2012, is significant.

The distribution of vehicles involved in speeding-related fatal intersection crashes by type of vehicle is as follows: passenger cars, 42.1 percent; light trucks, 32.3 percent; motorcycles, 17.4 percent; large trucks and buses, 6.5 percent; and other, 1.8 percent.

Figure 19 – Distribution of Vehicles Involved in Speeding-related Fatal Intersection Crashes by Type of Vehicle
(Source: FARS 2010-2012)

When analyzing each vehicle type separately to determine the percentage involved in speeding-related fatal intersection crashes, approximately 30 percent of motorcycle-involved intersection crashes–the highest percentage of all vehicle types–were considered speeding-related.

The percentage of vehicles involved in speeding-related fatal intersection crashes by type of vehicle is as follows: motorcycles, 28.6 percent; passenger cars, 22.2 percent; light trucks, 19.1 percent; and large trucks and buses, 16.1 percent.

Figure 20 – Percentage of Vehicles Involved in Speeding-related Fatal Intersection Crashes by Type of Vehicle
(Source: FARS 2010-2012)

CRASH TYPE

Figure 21 shows that, at more than 41 percent, angle crashes make up the highest percentage of speeding-related fatal intersection crashes for the 2010-2012 period, and collisions with non-vehicle objects (e.g., pedestrians, bicycles, roadside features, etc.) follows closely behind, accounting for almost 40 percent. Notably, although rear-end crashes make up just over 6 percent of all fatal intersection crashes, they more than doubled that percentage (13.3 percent) for speeding-related fatal intersection crashes. Around 44 percent of rear-end fatal intersection crashes took place in rural areas.

Figure 21 – Distribution of Speeding-related Fatal Intersection Crashes by Crash Type
(Source: FARS 2010-2012)

When looking at the crash types independently, additional insight can be gained on the nature of fatal intersection crashes. Figure 22 shows the distribution of vehicles involved in speeding-related fatal angle crashes at intersections by vehicle type during the study period. Once again, motorcycles are the predominant vehicle type in these crashes. Almost 40 percent of the vehicles involved in speeding-related fatal angle crashes were motorcycles.

The distribution of vehicles involved in speeding-related fatal angle crashes at intersections by vehicle type is as follows: motorcycles, 36.8 percent; passenger cars, 33.8 percent; light trucks, 25 percent; large trucks and buses, 3.1 percent; and other, 1.3 percent.

Figure 22 – Distribution of Vehicles Involved in Speeding-related Fatal Angle Crashes at Intersections by Vehicle Type
(Source: FARS 2010-2012)

4.2.2 Strategies

FHWA, the National Highway Transportation Safety Administration (NHTSA), the American Association of State Highway and Transportation Officials (AASHTO), Institute of Transportation Engineers (ITE), and other organizations have developed a number of potential resources for agencies to use in identifying successful strategies for improving intersection safety. Many of these strategies and countermeasures are just as applicable for addressing speeding-related intersection crashes. By reviewing the national data, investigating the state of the practice, and conducting interviews with national experts, some key issues or focus areas relating to speeding-related intersection fatal crashes were identified. These strategies were discovered through agency interviews and published resources.²⁷ Every situation or location is unique, and agencies should exercise engineering judgment when determining the appropriate solution for their specific crash concerns.

Issue: National data shows nearly 53 percent of vehicles involved in speeding-related intersection fatal crash types were traveling on arterial roadways.

Potential strategies:

Appropriate speed limits. Ensure speed limits are set appropriately by completing an engineering speed study and employing FHWA's USLIMITS2.
Improve visibility or conspicuity of intersection. Ensure sight distance is adequate, clear sight distance triangles, install advance signing, or enhance striping. For signalized intersections, install backplates or reflectorized backplates; use mast arms instead of span-wire. For unsignalized intersections, install larger and/or more reflective signing.
Traffic calming. Incorporate traffic calming measures at intersections along arterials, such as constructing roundabouts or mini roundabouts, applying lane narrowing techniques (using striping or a combination of striping and rumble strips), or creating median islands.
Signal timing. Create a plan to systematically review signal timings at intersections on these types of roadways. Ensure the yellow and all-red clearance intervals are appropriate for the speed limit and the intersection geometry. Coordinate signals on appropriate roadways to promote progression and a uniform speed.
Dilemma zone protection measures. Install advance detection sensor equipment that adjusts the start time of the yellow-signal phase either earlier or later based on observed vehicle locations and speeds; install advance warning signs that notify drivers of the need to stop at an upcoming signalized intersection.
Enforcement. Determine specific arterial roadway corridors with a high speeding-related intersection crash history and conduct high-visibility enforcement and education efforts. Use red-signal enforcement lights²⁸ (i.e., "tattletale lights"), which assist law enforcement officers in more efficiently and safely issuing citations for drivers at an intersection. If the State or local jurisdiction allows, install red light running automated enforcement systems (see Fixing America's Surface Transportation Act [FAST Act], Section 1401, for federal funding rules on these systems).

Issue: Motorcyclists have a high risk of being involved in speeding-related intersection fatal crashes.

Potential strategies:

Targeted education campaigns. Create educational campaigns that target motorcyclists or motorcycle clubs to promote safe riding. Campaigns can also target "other drivers" to promote increased awareness of motorcyclists.
Conspicuity of motorcyclists. Encourage high visibility apparel and equipment for riders.
Helmet laws. Support laws that require approved helmet use. NHTSA estimates that more than 700 lives could be saved if all motorcyclists had worn helmets.²⁹
Rider training. Work with appropriate organizations to coordinate and/or require training before a rider can be licensed.
Emergency responder training. Engage and ensure emergency response personnel are properly trained to understand, identify, and treat the specific types of injuries common to motorcycle crashes (e.g., pelvic injuries).

Issue: Angle crashes make up the highest percentage of speeding-related fatal intersection crashes at over 41 percent.

Potential strategies:

Roundabouts and mini roundabouts. Roundabouts and mini roundabouts eliminate crossing conflicts that are present at conventional intersections, reducing both the total number of potential conflict points as well as the most severe of those conflict points.
U-turn-based intersection designs. Both the restricted crossing U-turn intersection (RCUT) and median U-turn designs reduce overall conflict points significantly compared to conventional intersections. More importantly, certain RCUT designs have the potential to eliminate all "crossing" conflict points, which contribute to the most severe angle crashes (see Fixing America's Surface Transportation Act [FAST Act], Section 1401, for federal funding rules on these systems).
Automated red-light enforcement. If the State or local jurisdiction allows installation of this enforcement method, photo enforcement can reduce red-light running and associated angle crashes (see Fixing America's Surface Transportation Act [FAST Act], Section 1401, for federal funding rules on these systems).

Issue: Speeding-related fatal intersection crashes are more likely to happen in rural areas.

Potential strategies:

Improve visibility or conspicuity of intersections. Ensure sight distance is adequate, clear sight distance triangles, install advance signing, enhance signing and striping. Install lighting if there are high occurrences of speeding-related intersection crashes at night.
Transverse rumble strips. Transverse rumble strips (i.e., in-lane rumble strips) are raised or grooves placed across the travel lane to supplement signing and alert drivers of the need to reduce speed as they approach an intersection.
High friction surface treatment.³⁰ Effective in addressing locations with friction or wet crash issues, high friction surface treatments secure a thin layer of specially engineered, durable, high-friction aggregates as a topping on resins or polymers – usually urethane, silicon, or epoxy – with a binder. While this countermeasure does not reduce speeding vehicles, it provides long lasting skid resistance.
Detection control systems. Install advance detection sensors, which adjusts the start time of the yellow-signal phase either earlier or later based on observed vehicle locations and speed; install advance warning signs that notify drivers of the need to stop at an upcoming signalized intersection
Rural ITS solutions. Install ITS solutions such as intersection collision warning systems (ICWS), speed feedback signs, speed activated warning or speed limit reminder signs, or other signs or beacons that notify the side street or major street vehicle of an approaching vehicle. Variable speed limit signs may be beneficial in areas where inclement weather is common.
Transverse or optical speed bars. These pavement markings are generally spaced at gradually decreasing distances and are used to increase the drivers' perception of speed and cause them to reduce speed.
U-turn-based intersection designs. U-turn-based intersection designs, such as the RCUT or median U-turn can be beneficial on higher-speed rural divided highways by reducing conflict points and the probability of severe types of crashes. Certain RCUT designs have the potential to eliminate all "crossing" conflict points, which contribute to the most severe angle crashes.
Left and right turn lanes. While adding left and right turn lanes may not reduce speeds, these auxiliary lanes allow the turning vehicles to move out of the main travel lanes, reducing the likelihood of rear-end speeding-related crashes or sudden lane-changing avoidance maneuvers. Consider offset left and right turn designs in order to provide better sight distance at the intersection.

Issue: While roundabouts and mini roundabouts are two of the most effective measures for managing speed through intersections and reducing severe crashes, initial cost or public sentiment often precludes widespread implementation in favor of conventional intersection designs and low-cost improvements.

Potential strategies

Education and outreach. Educate the public and government officials on the benefits and safety of roundabouts.
Life cycle cost. Calculate the life cycle cost, including the safety cost, in the planning and evaluation of intersection treatments.
Roundabout-first policy. Implement an agency policy that requires consideration and evaluation of a roundabout as an alternative during a reconstruction or new intersection project. Typically, these types of policies indicate that, if the analysis shows a roundabout is a feasible alternative, the roundabout should then be considered a preferred option due to its great safety and operational benefits. References and resources for speed management countermeasures are available on FHWA's Speed Management website. FHWA has published desktop references that summarize studies on the effectiveness of engineering countermeasures in reducing crashes and managing speed.³¹ As an additional resource, the CMF Clearinghouse provides a comprehensive database of CMFs along with supporting documentation to help agencies identify potential countermeasures and effectiveness.³²

4.3 Pedestrians/Bicyclists and Speed Management

Transportation safety is not only about motor vehicle safety, it also encompasses protecting vulnerable users. Pedestrian safety is a primary concern in communities across the United States, with pedestrians accounting for approximately 14 percent of traffic fatalities.³³ In 2013, bicyclist deaths accounted for over 2 percent of all motor vehicle traffic fatalities.³⁴,³⁵

4.3.1 National Crash Data Analysis Trends

The speeding-related crash analysis completed on the national data included information on both pedestrians and bicyclists involved in fatal crashes. Approximately 8 percent of fatal crashes involving a pedestrian or bicyclist were speeding related, and 73 percent occurred predominantly in an urban setting. When looking at all fatal pedestrian and bicycle crashes, the speeding-related crashes were almost twice as likely to be hit and run. While the complete report is included in Appendix A, some of the more significant results are listed below.

LOCATION

Locations for speeding-related fatal pedestrian and bicycle crashes are summarized in Figure 23. The majority of these fatal crashes did not take place at an intersection. These locations, making up nearly 55 percent of fatal speeding-related pedestrian and bicycle crashes, may indicate mid-block crossings. Shoulders, roadsides, or parking lanes accounted for approximately 15 percent.

Figure 23 – Distribution of Speeding-related Fatal Pedestrian and Bicycle Crashes by Location
(Source: FARS 2010-2012)

SPEED LIMIT

The distribution of vehicles involved in speeding-related pedestrian and bicycle fatal crashes by posted speed limit is shown in the figure below. More than 50 percent occurred on roads with speed limits between 30 mph and 45 mph, although roadways with these types of speed limits are more likely to have higher pedestrian and bicyclist volumes. Conversely, roads with speed limits of 60 mph or more, which account for almost 20 percent of the vehicles involved in these types of fatal crashes, typically have fewer pedestrians and bicyclists.

Figure 24 – Distribution of Speeding-related Fatal Pedestrian and Bicycle Crashes by Location
(Source: FARS 2010-2012)

DRIVER CHARACTERISTICS

As with the other focus areas, males also make up more than 70 percent of drivers in speeding-related pedestrian and bicycle fatal crashes. The age group that is more likely to be involved in speeding-related fatal pedestrian and bicycle crashes is quite different than those involved in speeding-related roadway departure and intersection crashes. The distribution of drivers by age and gender category is shown in Figure 25 (the sum of all bars equals 100 percent). Males aged 45 to 64 make up nearly 30 percent of all speeding-related fatal pedestrian and bicycle crashes. Because of hit and run crashes, driver characteristics in all crashes may not be identified.

The distribution of drivers involved in speeding-related fatal pedestrian and bicycle crashes by age and gender indicates that a men were more likely than women to be involved in these types of crashes by a significant amount. Males in the 45-54 age range (15.9 percent), the 55-64 age range (911.8 percent), and the 25-34 age range (10.7 percent) had the greatest number of these types of crashes. Females in the 45-54 age range (5.5 percent), 25-34 age range (4.9 percent), and 55-64 age range (3.8 percent) had the greatest number of these type of crashes.

Figure 25 – Distribution of Speeding-related Fatal Pedestrian and Bicycle Crashes by Location
(Source: FARS 2010-2012)

TIME OF DAY

As shown in Figure 26, the most problematic time period was 6 p.m. to midnight, during which period nearly 40 percent of speeding-related fatal pedestrian and bicycle crashes occurred. The period with the second highest rate of crashes was from midnight to 5 a.m., during which time almost 20 percent of fatal pedestrian and bicycle crashes occurred.

The distribution of speeding-related fatal pedestrian and bicycle crashes by hour of day is as follows: 6 p.m. to midnight, 39.5 percent; midnight to 5 a.m., 19.8 percent; 10 a.m. to 4 p.m., 15 percent; 5 to 8 a.m., 13.1 percent; 4 to 6 p.m., 7.0 percent; and 8 to 10 a.m., 5.6 percent.

Figure 26 – Distribution of Speeding-related Fatal Pedestrian and Bicycle Crashes by Hour of Day
(Source: FARS 2010-2012)

4.3.2 Strategies

"Every transportation agency, including DOT, has the responsibility to improve conditions and opportunities for walking and bicycling and to integrate walking and bicycling into their transportation systems."

— U.S. DOT Policy Statement on Bicycle and Pedestrian Accommodation Regulations and Recommendations, March 2010

Addressing speeding-related, fatal pedestrian and bicycle crashes may be more challenging or overwhelming to agencies compared to the other focus areas. The lack of robust data and convincing leaders to prioritize pedestrian and bicyclist safety are just some of the hurdles that agencies must overcome. Below are some of the common issues regarding speeding-related pedestrian and bicycle crashes that were identified both by agencies and by national data analysis results. The recommended strategies were identified through agency interviews and published resources.³⁶ Every situation or location is unique, and agencies should exercise engineering judgment for determining the appropriate solution for their specific crash concerns. Although many of these strategies focus on pedestrian safety, many are also applicable to bicycle safety improvements.

Issue: It is challenging for agencies to identify clusters or problem locations for improving pedestrian safety because of data quality and quantity.

Potential strategies

Data improvement plan. Work together with law enforcement, emergency responders, community leaders, and special interest groups to improve and identify ways to capture information on the amount of pedestrians in a particular area, pedestrian injuries, and excessive speeding violations
Pedestrian facilities review. Create an overall plan for assessing existing pedestrian facilities and identify gaps and needs relating to pedestrian safety. Activities might include: accurately inventorying existing facilities, identifying sidewalk gaps, verifying pedestrian facilities are constructed to meet ADA requirements, checking for properly marked crosswalks, and reviewing pedestrian cycle lengths at signalized intersections. These activities can help identify potential problem areas where pedestrians may be more vulnerable to speeding-related crash risks.
Maintain inventories. Develop a process to keep crash and facility inventory data up to date.

Issue: National data analysis revealed nearly 40 percent of speeding-related fatal pedestrian and bicycle crashes took place between 6 p.m. and midnight. The period with the second greatest number of crashes, almost 20 percent, was from midnight to 5 a.m.

Potential strategies

Lighting. In areas where there is a high amount of pedestrian activity, install lighting to illuminate intersections and crosswalks. Ensure existing lighting at intersections and crosswalks is designed properly for maximum safety and illuminance of pedestrians.
Rectangular rapid flash beacons. Rectangular rapid flash beacons (RRFB) are user-activated (or detection activated) amber LEDs that supplement warning signs at unsignalized intersection or midblock crossings. RRFBs are shown to significantly increase driver yielding behavior at crosswalks when supplementing standard pedestrian crossing warning signs and markings.³⁷
In-roadway warning lights. Each side of a crosswalk is lined with a series of actuated, amber lights embedded in the roadway that light up to warn approaching drivers when a pedestrian is in or near the marked crosswalk. The MUTCD contains information on the use and installation of in-roadway warning lights.
Public outreach and education. Educate pedestrians and bicyclists on the importance of wearing reflective clothing or installing reflectors on bicycles for visibility at nighttime.

Issue: The majority of pedestrian speeding-related fatal crashes do not take place at an intersection.

Potential strategies

Raised median or refuge islands. Raised medians or islands provide for a safe area for pedestrians, so they do not have to cross the entire street at once and only need to negotiate one direction of traffic at a time.
Pedestrian hybrid beacon (i.e., High intensity Activated crossWalK or "HAWK"). The pedestrian-activated warning device is located on the roadside or on mast arms over midblock pedestrian crossings. In general, they should be used if gaps in traffic are not adequate to permit pedestrians to cross, if vehicle speeds on the major street are too high to permit pedestrians to cross, or if pedestrian delay is excessive.³⁸
Rectangular rapid flash beacons. Rectangular rapid flash beacons (RRFB) are user-activated (or detection activated) amber LEDs that can supplement warning signs at mid-block crossings. RRFBs are shown to significantly increase driver yielding behavior at crosswalks when supplementing standard pedestrian crossing warning signs and markings.³⁹
Barriers to prevent unwanted crossings. Identify areas where pedestrians are making decisions to cross at unsafe locations and install barriers that prevent crossing.
Enforcement, education, and outreach. Plan targeted enforcement and education campaigns for pedestrians on safe crossing habits, the risks of walking alongside higher-speed roadways, promote walking against traffic, etc., along with educating drivers to slow down and yield to pedestrians.

Issue: Many roadways have historically been designed with vehicles as the primary user; little consideration has traditionally been given to non-motorized users.

Potential strategies

Context sensitive design. Incorporate context sensitive design into agency policy by examining needs of communities and the users of the roadway. Incorporate pedestrian and other users in the purpose and need for projects where appropriate.
Road Diets. With the four-lane to three-lane conversion being the most common lane reconfiguration, Road Diets have been proven to reduce top-end speeders as well as to allow a more pedestrian- and bicycle-friendly design by reallocating space for bicycle lanes, sidewalks, pedestrian refuge islands, etc.⁴⁰
Accommodating pedestrians and bicyclists. Designers can review FHWA's Accommodating Bicycle and Pedestrian Travel: A Recommended Approach. FHWA's Separated Bike Lane Planning and Design Guide also provides practical information and promotes design flexibility for implementing separated bicycle lanes.
Bicycle-friendly rumble strips. While rumble strips provide tremendous safety benefits for motorists, they may cause concern for bicyclists. Design opportunities exist whereby the impacts of rumble strips on other road users can be reduced by adjusting the strips' dimensions and location.⁴¹

Speed management countermeasures references are available on FHWA's Speed Management website. FHWA has published desktop references that summarize studies about the effectiveness of engineering countermeasures in reducing crashes and managing speed.⁴² The CMF Clearinghouse provides a comprehensive database of CMFs along with supporting documentation to help agencies identify potential countermeasures and effectiveness.⁴³

¹⁴ FHWA Office of Safety, "Focused Approach to Safety – Purpose of the Focused Approach" Web page. Available at: http://safety.fhwa.dot.gov/fas/. Accessed December 8, 2015. [ Return to note 14. ]

¹⁵ See Appendix A, Evaluation of the Role of Speeding in Crashes and Safety-critical Events. [ Return to note 15. ]

¹⁶ FHWA Office of Safety, "Roadway Departure Safety" Web page. Available at: http://safety.fhwa.dot.gov/roadway_dept/. Accessed December 8, 2015. [ Return to note 16. ]

¹⁷ Ibid. [ Return to note 17. ]

¹⁸ See Appendix A, Evaluation of the Role of Speeding in Crashes and Safety-critical Events. [ Return to note . ]

¹⁹ Additional resources are listed in Appendix C. [ Return to note 19. ]

²⁰ FHWA developed USLIMITS2 to help practitioners set reasonable, safe, and consistent speed limits for specific roadway segments. It is applicable to all types of roads ranging from rural local roads and residential streets to urban freeways. For additional information, visit http://safety.fhwa.dot.gov/uslimits [ Return to note 20. ]

²¹ FWHA, Evaluation of Dynamic Speed Feedback Signs on Curves: A National Demonstration Project, FHWA-HRT-14-020 (Washington, DC: FHWA, January
2015). Available at: https://www.fhwa.dot.gov/publications/research/safety/14020/index.cfm [ Return to note 21. ]

²² FHWA, "High Friction Surface Treatments Frequently Asked Questions" FHWA-CAI-14-019. (Washington, DC: FHWA, 2014). Available at: https://www.fhwa.dot.gov/innovation/everydaycounts/edc-2/pdfs/fhwa-cai-14-019_faqs_hfst_mar2014_508.pdf [ Return to note 22. ]

²³ Safety Edge_SM provides a transition for vehicles to return to the pavement more smoothly and easily by shaping the edge of pavement to 30 degrees and eliminating vertical drop-off. More information on Safety EdgeSM is available at https://www.fhwa.dot.gov/innovation/everydaycounts/edc-1/safetyedge.cfm [ Return to note 23. ]

²⁴ 24 FHWA, A Desktop Reference of Potential Effectiveness in Reducing Speed, 2014, available at http://safety.fhwa.dot.gov/speedmgt/ref_mats/eng_count/2014/reducing_speed.cfm, and FHWA, A Desktop Reference of Potential Effectiveness in Reducing Crashes, 2014, available at http://safety.fhwa.dot. gov/speedmgt/ref_mats/eng_count/2014/reducing_crashes.cfm, accessed September 4, 2015 [ Return to note 24. ]

²⁵ CMF Clearinghouse, available at: http://www.cmfclearinghouse.org [ Return to note 25. ]

²⁶ FHWA Office of Safety, "Motorcycle Safety" Web page. Available at: http://safety.fhwa.dot.gov/motorcycles. Accessed December 8, 2015. [ Return to note 26. ]

²⁷ Additional resources are listed in Appendix C. [ Return to note 27. ]

²⁸ FHWA, "Red-Signal Enforcement Lights," FHWA-SA-09-005 (Washington, DC: FHWA 2009). Available at: http://safety.fhwa.dot.gov/intersection/resources/techsum/fhwasa09005 [ Return to note 28. ]

²⁹ NHTSA, "Traffic Safety Facts, 2013 Data: Motorcycles," DOT HS 812 148 (Washington, DC: NHTSA, 2015). Available at: http://www-nrd.nhtsa.dot.gov/Pubs/812148.pdf [ Return to note 29. ]

³⁰ FHWA, High Friction Surface Treatments Frequently Asked Questions, available at: https://www.fhwa.dot.gov/everydaycounts/edctwo/2012/pdfs/fhwa-cai-14-019_faqs_hfst_mar2014_508.pdf [ Return to note 30. ]

³¹ FHWA, A Desktop Reference of Potential Effectiveness in Reducing Speed, 2014, available at http://safety.fhwa.dot.gov/speedmgt/ref_mats/eng_count/2014/reducing_speed.cfm, and FHWA, A Desktop Reference of Potential Effectiveness in Reducing Crashes, 2014, available at http://safety.fhwa.dot.gov/speedmgt/ref_mats/eng_count/2014/reducing_crashes.cfm, accessed September 4, 2015. [ Return to note 31. ]

³² CMF Clearinghouse, available at: http://www.cmfclearinghouse.org/

[ Return to note 32. ]

³³ FHWA, A Desktop Reference of Potential Effectiveness in Reducing Speed, 2014, available at http://safety.fhwa.dot.gov/speedmgt/ref_mats/eng_count/2014/reducing_speed.cfm, and FHWA, A Desktop Reference of Potential Effectiveness in Reducing Crashes, 2014, available at http://safety.fhwa.dot.gov/speedmgt/ref_mats/eng_count/2014/reducing_crashes.cfm, accessed September 4, 2015. [ Return to note 33. ]

³⁴ The term bicyclist includes bicyclists and other cyclists including riders of two-wheel, non-motorized vehicles, tricycles, and unicycles powered solely by pedals. [ Return to note 34. ]

³⁵ NHTSA, "Traffic Safety Facts, 2013 Data: Bicyclists and Other Cyclists," DOT HS 812 151 (Washington, DC: NHTSA, 2015). Available at: http://www-nrd.nhtsa.dot.gov/Pubs/812151.pdf [ Return to note 35. ]

³⁶ Additional resources are listed in Appendix C. [ Return to note 37. ]

³⁷ FHWA, Rectangular Rapid Flash Beacons (RRFB), FHWA-SA-09-009, May 2009. Available at: http://safety.fhwa.dot.gov/intersection/conventional/unsignalized/tech_sum/fhwasa09009/ [ Return to note 37. ]

³⁸ FHWA, Pedestrian Hybrid Beacon, FHWA-SA-12-012, October 2014. Available at: http://safety.fhwa.dot.gov/provencountermeasures/fhwa_sa_12_012.cfm [ Return to note 38. ]

³⁹ FHWA, Rectangular Rapid Flash Beacons (RRFB), FHWA-SA-09-009 (Washington, DC: FHWA, 2009). Available at: http://safety.fhwa.dot.gov/intersection/conventional/unsignalized/tech_sum/fhwasa09009/ [ Return to note 39. ]

⁴⁰ FHWA, Road Diet Informational Guide, FHWA-SA-14-028 (Washington, DC: FHWA, November 2014). Available at: http://safety.fhwa.dot.gov/road_diets/info_guide [ Return to note 40. ]

⁴¹ FHWA, "Technical Advisory: Shoulder and Edge Line Rumble Strips," T 5040.39, Revision 1 (Washington, DC: FHWA, 2011). Available at: http://safety.fhwa.dot.gov/roadway_dept/pavement/rumble_strips/t504039 [ Return to note 41. ]

⁴² FHWA, A Desktop Reference of Potential Effectiveness in Reducing Speed, FHWA-SA-14-101 (Washington, DC: FHWA, 2015). Available at http://safety.fhwa.dot.gov/speedmgt/ref_mats/eng_count/2014/reducing_speed.cfm [ Return to note 42. ]

⁴³ CMF Clearinghouse, available at: http://www.cmfclearinghouse.org [ Return to note 43. ]

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