Intersection Safety Implementation 

Plan Process 

U.S. Department of Transportation 

Federal Highway Administration 

FHWA-SA-10-010 
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Foreword 

This final report has been designed to provide State Safety and Traffic Engineers with a process 

to use for creating an intersection safety implementation plan based upon their Strategic 

Highway Safety Plan (SHSP). While many SHSPs define the State’s overarching safety goals, 

typically in terms of fatality and/or injury reduction by a specific year, they do not always define 

the countermeasures, deployment levels, costs, and actions needed to achieve the goal. 

It is hoped that the 10-step process detailed in this report will guide and assist State Safety 

and Traffic Engineers in identifying the countermeasures, strategies, deployment levels, 

implementation steps, actions, and costs necessary to achieve the intersection safety goals of 

the SHSP. 

This report is one in a series on the topic of Intersection Safety Implementation provided 

by the Federal Highway Administration’s Office of Safety. Other complimentary documents 

include Example Data Analysis Package and Straw Man Outline, Example Intersection Safety 

Implementation Plan, and Intersection Safety Implementation Plan Workshop and can be 

found on the FHWA Office of Safety website at http://safety.fhwa.dot.gov/intersection/. 
Technical Report Documentation Page 

1. Report No. 

FHWA-SA-10-010 

2. Government Accession No. 3. Recipient’s Catalog No. 

4. Title and Subtitle 

Intersection Safety Implementation Plan Process 

5. Report Date 

November 2009 

6. Performing Organization Code 

7. Author(s) 

Tom Bryer, P.E. 

8. Performing Organization Report No. 

9. Performing Organization Name and Address 

Science Applications International Corporation (SAIC) 

8301 Greensboro Drive 

McLean, VA 22102 

10. Work Unit No. (TRAIS) 

11. Contract or Grant No. 

DTFH61-05-D-00025, Task T-06-003 

12. Sponsoring Agency Name and Address 

United States Department of Transportation 

Federal Highway Administration 

Office of Safety 

1200 New Jersey Ave., SE 

Washington, DC 20590 

13. Type of Report and Period Covered 

14. Sponsoring Agency Code 

HSSD 

15. Supplementary Notes 

George E. Rice, Jr. COTM 

16. Abstract 

To achieve their safety goals, many States select intersection safety as an emphasis area as part of their Strategic Highway 

Safety Plan (SHSP). However, while SHSPs may identify strategies to promote intersection safety, they lack the depth of information needed to establish an action plan for implementing the strategies necessary to achieve the safety goals. This document provides a 10-step process that guides and assists State Safety and Traffic Engineers in identifying the countermeasures, 

strategies, deployment levels, implementation steps, actions, and costs necessary to achieve the intersection safety goals of 

the SHSP. 

17. Key Words 

Intersection safety, action plan, intersection safety strategies, goals, implementation plans, strategic highway safety 

plan. 

18. Distribution Statement 

No restrictions. This document is available to the 

public from: The National Technical Information 

Service, Springfield, VA 22161. 

19. Security Clasif. (of this report) 

Unclassified 

20. Security Clasif. (of this page) 

Unclassified 

21. No. of Pages 

60 

21. Price 

N/A 

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

 

Table of Contents 

Overview................................................................................................................................................................. 1 

STEP 1: Set the Intersection Crash Reduction Goal ........................................................................................ 2 

STEP 2: Expand the Current Approach for Achieving the Crash Reduction Goal...................................... 4 

Traditional Approach ......................................................................................................................................................................................4 

Systematic Approach.....................................................................................................................................................................................5 

Comprehensive Approach..........................................................................................................................................................................9 

STEP 3: Identify Intersection Countermeasure Type to be Completed.....................................................10 

Countermeasure Descriptions..............................................................................................................................................................10 

Systematic Approach.................................................................................................................................................................10 

Comprehensive Approach.....................................................................................................................................................15 

Traditional Approach..................................................................................................................................................................16 

Selecting Countermeasures....................................................................................................................................................................16 

STEP 4: Analyze Crash and Applicable Roadway Data................................................................................. 22 

The Data Analysis Process........................................................................................................................................................................22 

Separate Intersection Crashes into Sub-Groups.......................................................................................................22 

Determine Target Crash Types.............................................................................................................................................22 

Calculate Average Crash Costs and Crash Severities..............................................................................................25 

Determine Distribution of Crash Densities..................................................................................................................26 

Prepare Data Analysis Package ............................................................................................................................................27 

Data Problems and Solutions.................................................................................................................................................................28 

Data Quality.....................................................................................................................................................................................28 

Data Availability.............................................................................................................................................................................32 

Exposure and Rates.....................................................................................................................................................................33 

Intersections with Multiple Countermeasures...........................................................................................................34 

STEP 5: Develop a Straw Man Outline ............................................................................................................. 35 

Establish Threshold Crash Levels..........................................................................................................................................................35 

Develop Detailed Straw Man Tables for Each Countermeasure.......................................................................................37 

Compile a Summary Straw Man Outline........................................................................................................................................38 

STEP 6: Conduct a Workshop of Key Stakeholders and Follow-Up Implementation .................................. 

Planning Meeting................................................................................................................................................ 41 

Two-Day Workshop......................................................................................................................................................................................42 

Half-Day Follow-Up Implementation Planning Meeting......................................................................................................44 

STEP 7: Develop a Draft Intersection Safety Implementation Plan .......................................................... 45 

STEP 8: Present the Draft Intersection Safety Implementation Plan to Upper Management ............. 46 

STEP 8: Present the Draft Intersection Safety Implementation Plan to Upper Management ............. 47 

STEP 10: Implement the Plan, Monitor Progress, and Evaluate Results ................................................... 48 

iii 
List of Tables 

Table 1: Sample Fatalities for State B..................................................................................................................................2 

Table 2: Sample Fatality Rates for State A .........................................................................................................................3 

Table 3: Typical Distribution of Fatalities within a State over a 5-Year Period............................................................5 

Table 4: USDOT Fatality and Injury Costs...........................................................................................................................6 

Table 5: Targeted Crash Types by Traffic Control, Ownership, and Area......................................................................7 

Table 6: Typical Rates for Fatalities per 100 Crashes .......................................................................................................7 

Table 7: Typical Distribution of Total Crashes at Rural State Stop-Controlled Intersections – 

5 Years of Data .........................................................................................................................................................8 

Table 8: Typical Distribution of Total Crashes at Rural State Signalized Intersections – 

5 Years of Data .........................................................................................................................................................8 

Table 9: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Countermeasures at Stop-Controlled Intersections...........................11 

Table 10: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Countermeasures at J-Turn Stop-Controlled Intersections...............12 

Table 11: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Countermeasures at Signalized Intersections .....................................13 

Table 12: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Lighting Countermeasures at Unlit or Poorly Lit Intersections ........14 

Table 13: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Skid Resistance Countermeasures at Intersections with High Rates 

of Low-Friction Crashes........................................................................................................................................14 

Table 14: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Countermeasures at Stop-Controlled Intersections with 

High-Speed Approaches ......................................................................................................................................15 

Table 15: Crash Reduction Factors, Default Expected Life, and Estimated Implementation Costs for Corridor 

and Municipal Enforcement Countermeasures...............................................................................................15 

Table 16: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated 

Implementation Cost Ranges for Countermeasures for Education-Enforcement Strategies at 

Signalized Intersections to Reduce Red-Light Running ................................................................................16 

Table 17: Crash Reduction Factors, Additional Application Factors, and Estimated Implementation Costs for 

Traditional Approach Countermeasures...........................................................................................................17 

Table 18: Template for Documenting Countermeasure Selection................................................................................18 

Table 19: Typical Types of Crashes and Associated Countermeasures ........................................................................23 

iv 
List of Tables Continued 

Table 20: Angle Crashes – Signalized Intersections – 5 Years of Data..........................................................................26 

Table 21: Sample Listing of Crashes per Intersection – State, Rural, Stop-Controlled Intersections – 

5 Years of Data........................................................................................................................................................27 

Table 22: Summarized Frequency Distribution – State, Rural, Stop-Controlled Intersections – 

5 Years of Data .......................................................................................................................................................28 

Table 23: Example Distribution of Crashes by Intersection – Rural/Urban .................................................................29 

Table 24: Example Distribution of Night Crashes in Rural Areas by Intersection.......................................................31 

Table 25: Example Distribution of Wet Pavement Crashes by Rural Intersection .....................................................32 

Table 26: Sample Matrix for State, Rural, Stop-Controlled Intersections ....................................................................34 

Table 27: Sample Distribution of Crashes at State Urban Signalized Intersections ..................................................36 

Table 28: Sample State Stop-Controlled Intersections - Basic Set of Sign and Marking Improvements ..............37 

Table 29: Sample Summary Straw Man..............................................................................................................................39 

Table 30: Typical Agenda for Intersection Safety Implementation Plan Workshop ..................................................42 

v 
List of Figures 

Figure 1: Process for Developing an Intersection Safety Implementation Plan ..........................................................1 

Figure 2: Levels of Information for the Systematic Approach Crash Data Analysis.....................................................6 

Figure 3: Examples of Basic Low-Cost Countermeasures for Stop-Controlled Intersections – Double Up 

Oversize Warning Signs, Double Stop Signs, Traffic Island on Stop Approach (if feasible), Street 

Name Signs, Stop Bars, and Double Warning Arrow at the Stem of T-Intersections ................................10 

Figure 4: Turn Restrictions at Multi-Lane Highways........................................................................................................12 

vi 


1. OVERVIEW 

All States have developed Strategic Highway Safety Plans (SHSP) and have established safety 

goals as part of the SHSP. 

States usually express safety goals in one of two ways: 

• A reduction in fatalities by a certain year. 

• A reduction in a combination of fatalities and injuries by a certain 

 year. 

Either of these options can be expressed in total numbers 

or rates. 

To achieve their safety goals, many States select 

intersection safety as an emphasis area. However, while 

SHSPs may identify strategies to promote intersection 

safety, they lack the depth of information needed to 

establish an action plan for implementing the strategies 

and achieving the safety goals. 

This document provides States a process (outlined 

in Figure 1) for creating an implementation plan to 

guide intersection safety implementation activities. It is 

specifcally targeted toward State Safety Engineers who 

have intersection safety as an emphasis area in their SHSP. 

Once complete, the implementation plan will include the 

activities, countermeasures, strategies, deployment levels, 

implementation steps, and funds necessary to achieve the 

intersection component of an SHSP goal. The following 

resources are available on the FHWA Intersection Safety 

web page (http://safety.fhwa.dot.gov/intersection/) to 

assist States in developing their implementation plans: 

• Example workshop presentation. 

• Example data analysis package and straw man outline. 

• Example intersection safety implementation plan. 

Expand Current 

Approach to 

Achieve Goal 

Set Crash 

Reduction Goal 

Identify 

Intersection 

Countermeasures 

Analyze Data, 

Identify Target 

Intersection 

Develop 

Straw Man 

Outline 

Conduct Workshop 

to Refne 

Countermeasures 

and Budget 

Develop 

Draft Intersection 

Safety 

Implementation 

Plan 

Present Draft 

to Upper 

Management 

Implement Plan, Monitor 

Progress, Evaluate Results 

Implement 

Management 

Suggestions 

Figure 1: Process for Developing an Intersection Safety Implementation Plan 

1 
STEP 1: 

Set The Intersection Crash Reduction Goal 

Many State SHSPs defne overall statewide safety goals. 

However, most SHSPs do not defne the portions 

of the goal to be addressed by emphasis area such 

as improving intersection safety, reducing roadway 

departures, improving pedestrian safety, reducing 

drinking and driving, and preventing aggressive driving. 

Because SHSPs often do not contain this level of detail, 

the number and types of countermeasures within an 

emphasis area needed to help achieve the overall goal 

can not be ascertained. This can result in less focus on 

deployment levels, costs, and statewide fatality reductions 

associated with the implementation of strategies and 

countermeasures. 

The overall SHSP goal may be expressed in terms of 

reductions in fatalities or some combination of fatalities 

and injuries by a certain time. It may also be expressed 

in terms of a reduction in the rate in crashes or fatalities 

per million vehicle miles traveled (VMT) or per 1,000 

population. Two examples of setting an intersection goal 

that is aligned with the SHSP goal are provided. 

Example 1 

SHSP Goal as a Reduction in Absolute Numbers 

If the SHSP goal is established in terms of a reduction in 

absolute numbers of fatalities and/or injuries by a given 

date, then information on the past trend of those fatalities 

and/or injuries is needed. 

Assume State B had 1,000 fatalities in 2007, 200 of which 

were intersection or intersection-related. State B has a 

goal to reduce total fatalities to no more than 850 by 2013. 

Over the past several years the fatalities have fuctuated as 

shown in Table 1. 

In 2013, it is expected that 9401 fatalities will occur. 

Additional strategies and eforts that result in 90 fewer 

fatalities are needed to achieve the goal. The intersection 

portion of that goal is 20 percent of 902, or 18 fewer 

intersection deaths annually. 

1 The expected number of fatalities in 2013 without additional strategies 

based upon past trends is the number of fatalities in 2007 (1,000) decreased by 

the results of existing trends and programs in place (1 percent annual decline in 

fatalities) for 6 years, or 1,000-(1,000x0.01x6) = 1,000-60 = 940. 

2 The additional fatality reduction to meet the 2013 goal is the expected 

number of fatalities in 2013 (940) decreased by the State’s 2013 fatality goal 

(850), or 940-850=90. 

Year Fatalities 

2007 1,000 

2006 923 

2005 975 

2004 1,021 

2003 1,064 

Table 1: Sample Fatalities for State B 

Example 2 

SHSP Goal Expressed as a Reduction in Rate 

If the SHSP goal is expressed as a rate, it is important to 

convert the rate to an expected reduction in fatalities 

and/or injuries by the time the goal is to be achieved. Two 

pieces of information are needed to properly make this 

determination: 

1. The fatality rate for each of the last 5 years of data. 

2. The expected annual change in VMT for each year up to the year in which 

the goal is expected to be achieved. 

Using the data from the last 5 years, the trend in the 

fatality rate can be estimated. The trend can predict 

the expected fatality rate in the year the goal is to be 

achieved. Then, using the predicted fatality rate and the 

estimated VMT in the goal year, the expected number of 

fatalities can be estimated. 

As an example, assume that State A also had 1,000 

fatalities in 2007, 200 of which were intersection or 

intersection-related. State A also has a goal to reduce the 

fatality rate from 1.30 in 2007 to 1.00 in 2013. The fatality 

rates over the past several years are provided in Table 2. 

Table 2 shows that the fatality rate is declining at an 

average rate of approximately 3 percent annually. 

Projecting ahead, the expected fatality rate in 2013, 

2 
 

assuming current trends continue and no added 

improvements are implemented, would be 1.12.3 

However, over the next 6 years VMT is expected to grow 

at a rate of 2.3 percent annually, or 13.8 percent over 2007 

VMT. The statewide VMT for 2007 is 76.9 billion. Growing 

by 13.8 percent, VMT is projected to be 87.5 billion by 

2013. 

With an estimated fatality rate of 1.12, the expected 

number of fatalities in 2013 would be 980.4 The goal 

for 2013 to achieve a fatality rate of 1.0 per 100 million 

VMT translates into 875 fatalities.5 Therefore, the net 

reduction in fatalities in 2013 from what is expected to 

the goal is 105.6 Strategies and eforts that result in 105 

Year Fatality Rate Per 

100 Million VMT 

2007 1.30 

2006 1.34 

2005 1.37 

2004 1.41 

2003 1.45 

Table 2: Sample Fatality Rates for State A 

3 The expected fatality rate in 2013 is the 2007 rate (1.30) decreased by 3 

percent per year for 6 years, or 1.30-(6x0.03) = 1.30-0.18 = 1.12. 

4 The expected number of fatalities in 2013 is the expected fatality rate in 

2013 (1.12 per 100 million VMT) multiplied by the projected VMT (87.5 billion), 

or (1.12x10-8)x(87.5 x109) = 980. 

5 The number of fatalities in 2013 if a 1.0 per 100 million VMT fatality rate is 

achieved is the fatality rate goal in 2013 (1.0 per 100 million VMT) multiplied by 

the VMT in 2013 (87.5 billion), or (1.0x10-8)x(87.5x109) = 875. 

6 The net reduction in fatalities in 2013 is the expected number of fatalities in 

2013 (980) decreased by the number of fatalities if the 1.0 per 100 million VMT is 

achieved (875), or 980-875 = 105. 

fewer fatalities are needed to achieve the goal. Since 20 

percent of the fatalities in 2007 occurred in intersection or 

intersection-related crashes, the intersection component 

of the overall goal can be estimated as 217 lives saved 

annually at intersections beginning in 2013. 

The economic losses that began in 2008 probably are 

associated with signifcant reductions in highway fatalities 

being realized in 2008. Less travel, particularly less 

discretionary travel, reduces the risk exposure for a serious 

crash. Most State SHSP goals are set approximately 5 years 

out (2012-2013). There is little technical basis to determine 

the length of the economic downturn. However, one 

assumption that may be made is that current economic 

conditions will be gone 5 years from now and should 

not be taken into consideration. That is, States could 

use 2007 as the last year of VMT and crash data in the 

analysis. States may also assume that VMT in 2012 will be 

equivalent to 2007 and expected fatalities in 2012 would 

be the mean of those occurring between 2002 and 2007. 

7 The intersection component of the overall goal is the net reduction in fatalities in 2013 (105) multiplied by the percentage of intersection or intersectionrelated crashes in 2007 (20 percent), or 105x0.20 = 21. 

Step 1 Action. 

Create an intersection crash reduction goal 

that is aligned with and complements the SHSP 

goal. 

3 
Step 2: 

Expand the Current Approach for Achieving the Crash Reduction Goal 

Traditionally, States have relied on one approach to 

address intersection safety problems – concentrating 

on improving those intersections with the highest 

concentrations of frequent and severe intersection 

crashes. However, in order to meet the intersection crash 

reduction goal established in Step 1, States likely will have 

to expand their approach. 

Three approaches to implementing intersection 

improvements probably will be needed to achieve the 

intersection crash reduction goal, particularly if the goal 

is designed to achieve a measurable statewide reduction 

in intersection fatalities or fatalities and incapacitating 

injuries. The approaches are: 

1. Traditional. 

2. Systematic. 

3. Comprehensive. 

If the intersection crash reduction goal is expressed 

in terms of a reduction in statewide fatalities and a 

substantial number of the fatalities occur on local roads 

and intersections, it is probable that these approaches 

need to be considered for application on both Stateand locally-owned intersections. As a rule of thumb, 

based upon experience gathered from States that 

have developed intersection safety plans, the relative 

importance of considering improvements on local 

intersections to achieve a statewide intersection goal can 

be refected in the proportion of intersection fatalities 

occurring at local intersections as indicated in the 

following ranges: 

• Less than 10 percent of statewide intersection fatalities occur at locallyowned intersections – Minimal importance to include locally-owned 

intersection improvements to achieve a statewide intersection crash 

reduction goal. 

• Between 10 and 20-25 percent of statewide intersection fatalities 

occur at locally-owned intersections – Benefcial and probably need to 

include some local intersection improvements to achieve a statewide 

intersection crash reduction goal. 

• Greater than 20-25 percent of statewide intersection fatalities occur at 

locally-owned intersections – Necessary to incorporate local intersection 

improvements to achieve a statewide intersection crash reduction goal. 

Traditional Approach 

Traditionally, States identify high-crash locations using 

crash data associated with a highway referencing system 

and, in some cases, trafc volume information. A formula 

to rank the locations by some combination of frequency, 

severity, rate, and crash trend is used to establish 

candidate locations for improvement. For each candidate 

location, crash diagrams are developed and studied to 

determine potential countermeasures for reducing future 

crash occurrence. A beneft-cost (B/C) analysis usually is 

performed to determine if the proposed improvement(s) 

is cost-efective. Those candidate locations with the best 

beneft-cost ratios may be selected for the limited funding 

available. Due to the relative high cost of many of these 

improvements, an average State may implement fewer 

than 100 traditional safety improvements annually. 

4 
 Road Ownership Number of Intersections 

with a Fatal Crash 

Intersections with 

One Fatal Crash 

Intersections with 

Two Fatal Crashes 

Intersections with 

Three Fatal Crashes 

State 683 647 34 2 

Local 336 328 7 1 

Table 3: Typical Distribution of Fatalities within a State over a 5-Year Period 

While this approach is important and needs to continue, it has minimal impact on reducing substantial numbers of 

future statewide fatalities and incapacitating injuries. If a State’s safety goal is measured by a reduction of statewide 

fatalities, there is little probability that a fatality would occur at the improvement sites during the next few years, even 

if the improvements had not been made. The probability of a future fatality occurring is a function of a number of 

independent variables, many of which safety engineers have no control over, including the following: 

• Speed. • Time of day. 

• Type of trafc control. 

• Crash location – urban or rural. 

• Age and health of drivers and occupants. 

• Emergency medical service (EMS) capabilities. 

• Distance to nearest hospital. 

• Type of crash. 

• Point of impact. 

• Type and mass of involved vehicle(s). 

• Safety belt usage. 

• Type of highway. 

• Weather and surface conditions. 

In addition, statistics from States indicate very few intersections have multiple fatal crashes over a 5-year period. A typical 

distribution of fatal crashes within a State over a 5-year period is shown in Table 3. 

If a fatal crash has occurred at an intersection, there is a relatively low probability that another one will occur within the 

next few years even if nothing is done to the intersection. If the statewide goal is expressed as a measured reduction of 

statewide fatalities (or fatalities and incapacitating injuries), then a traditional approach limited to a relatively nominal 

number of intersection improvements (less than approximately 100 annually) will be insufcient by itself to achieve 

the goal. Additional approaches to supplement the traditional approach are needed to achieve the intersection crash 

reduction goal. 

Systematic Approach 

The systematic approach is the opposite of the traditional approach in that it starts with a set of low-cost, efective 

countermeasures that the State is comfortable deploying and searches the crash data system to identify intersections 

where the countermeasures can be deployed cost-efectively. This approach is not limited to the highest crash 

locations. Typically, it focuses on treating the 3-6 percent of the intersections at which 25-45 percent of the statewide 

targeted intersection crashes exist. 

5 
All Intersection Crashes 

State Roads 

Rural 

Traffic 

Signal 

Traffic 

Signal 

Traffic 

Signal 

Traffic 

Signal 

Stop 

Sign 

Stop 

Sign 

Stop 

Sign 

Stop 

Sign 

Urban Rural Urban 

Local Roads 

Figure 2: Levels of Information for the Systematic Approach Crash Data Analysis 

In the systematic approach, intersection crash data are 

divided into three levels of information: State or local 

ownership, urban or rural location, and stop-controlled 

or signalized. As shown in Figure 2, all combinations 

of these levels (e.g., State, rural, stop-controlled, local 

urban signalized intersections) are used as a basis for 

analyzing the data. The breakdown of intersection 

ownership is important since State and local government 

implementation processes are often quite diferent. The 

separation of crashes by urban and rural area is necessary 

since crash severity (i.e., potential for a fatality) is much 

greater in rural areas for the same type of crash. The type 

of trafc control will dictate countermeasure treatment. In 

addition, the severity of similar types of crashes can difer 

signifcantly depending on the type of control (e.g., angle 

crashes at rural stop-controlled intersections are generally 

much more severe than angle crashes at rural signalized 

intersections). 

The cost of a fatality and all injury categories should 

be used in performing beneft/cost (B/C) analyses to 

determine the target crash threshold where it is costefective to apply a designated low-cost countermeasure 

or sets of countermeasures. These costs were updated 

in a February 5, 2008, US Department of Transportation 

(USDOT) memo, Treatment of the Economic Value of 

a Statistical Life in Departmental Analyses, and are 

summarized in Table 4. 

Severity Descriptor Cost Per Injury (2007 Dollars) 

K Fatal 5,800,000

A Incapacitating 402,000

B Evident 80,000

C Possible 42,000

PDO Property Damage Only 4,000

Table 4: USDOT Fatality and Injury Costs 

6 
Stop 

Stop State Urban       

Stop Local Rural      

State Rural      

Stop Local Urban       

Signal State Rural      

Signal State Urban       

Signal Local Rural      

Signal Local Urban       

Crash data analyses to determine if a countermeasure is cost-efective and can be considered for systematic 

deployment take crash types into consideration. Examples of crash type information needed to evaluate the potential 

deployment of various countermeasures are shown in Table 5. 

For each of the crash types in Table 5, two key pieces of crash data are needed to perform the analyses: 

• The severity of crashes, usually expressed in fatalities per 100 crashes for all of the statewide crashes over the past 5 years. The number of incapacitating 

injuries per 100 crashes may also be used to measure the impact of a countermeasure on incapacitating injuries. 

• The distribution of crashes per intersection using 5 or more years of crash data for all intersections that had at least one crash. For example, this 5-year 

distribution may show that 25-45 percent of statewide crashes at State, rural, stop-controlled intersections occur in 3-6 percent of the intersections. 

Trafc 

Control 

Crash Type 

Ownership Area 

Total Angle Left Turn Pedestrian Dark Wet Speeding 

Table 5: Targeted Crash Types by Trafc Control, Ownership, and Area 

Trafc 

Control 

Stop State Rural 2.40 3.12 2.08 3.79 3.04 11.76 

Stop State Urban 1.14 1.40 1.48 1.70 1.32 3.95 

Stop Local Rural 1.24 1.57 1.14 1.69 1.60 2.80 

Stop Local Urban 0.51 0.60 0.52 0.63 1.47 1.73 

Signal State Rural 1.60 3.53 2.53 1.88 0.44 16.98 

Signal State Urban 0.59 0.88 0.98 0.98 0.60 15.91 

Signal Local Rural 0.72 1.03 1.00 0.96 0.65 7.49 

Signal Local Urban 0.39 0.55 0.55 0.52 0.16 2.55 

Ownership Area 

Total Angle Left Turn Dark Wet Pedestrian 

Crash Type 

Table 6: Typical Rates for Fatalities per 100 Crashes 

An example of typical rates for fatalities per 100 crashes is provided in Table 6. This table shows that rural stop-controlled 

intersections have the highest severity rates, and that these rates generally increase at night. Pedestrian crashes have a 

much higher fatality rate than other types of crashes. Crashes at local intersections have a severity similar to, but may be 

slightly less than, those occurring at State intersections. It is important that each State compute its own values for these 

severity rates using the most current 5 years of crash data. 

Typical distributions for total crashes at State stop-controlled and signalized intersections are provided in Tables 7 and 8. 

7 
Number of 

Crashes per 

Intersection 

Cumulative 

50 and greater 7 7 0.07 428 1.42 

30-49 26 33 0.31 1,390 4.60 

20-29 91 124 1.16 3,506 11.60 

10-19 389 513 4.82 8,601 28.45 

5-9 1,033 1,546 14.51 15,347 50.76 

4 576 2,122 19.92 17,651 58.39 

3 1,008 3,130 29.38 20,675 68.39 

2 2,034 5,164 48.47 24,743 81.84 

1 5,489 10,653 100.00 30,232 100.00 

Total 10,653 10,653 100.00 30,232 100.00 

Number of 

Intersections Intersections Percent 

Cumulative 

Crashes Percent 

Table 7: Typical Distribution of Total Crashes at Rural State Stop-Controlled Intersections – 5 Years of Data 

Number of 

Crashes per 

Intersection 

Cumulative 

50 and greater 8 8 1.44 573 13.95 

30-49 23 31 5.57 1,407 34.26 

20-29 36 67 12.03 2,258 54.98 

10-19 56 123 22.08 3,012 73.34 

5-9 73 196 35.19 3,490 84.98 

4 31 227 40.75 3,614 88.00 

3 43 270 48.47 3,743 91.14 

2 77 347 62.30 3,897 94.89 

1 210 557 100.00 4,107 100.00 

Total 557 557 100.00 4,107 100.00 

Number of 

Intersections Intersections Percent 

Cumulative 

Crashes Percent 

Table 8: Typical Distribution of Total Crashes at Rural State Signalized Intersections – 5 Years of Data 

Two key observations can be made from Tables 7 and 8. In Table 7, if the 513 intersections that had 10 or more crashes 

were treated with low-cost countermeasures, almost 30 percent of the crashes that occur at State, rural, stop-controlled 

intersections could be impacted by the countermeasures. In Table 8, if the 31 intersections that had 30 or more crashes 

were treated with low-cost countermeasures, then over 34 percent of the crashes that occur at State, rural, signalized 

intersections could be impacted by the countermeasures. Conceptually, this is the essence of the systematic approach 

– identifying a relatively small set of intersections that comprise a substantial portion of the statewide crash problem, 

and treat the set with efective, low-cost countermeasures. 

8 
When performing the above analyses, it is important that 

a minimum of 5 full years of crash data be utilized. More 

years may be used if the data is available in the crash 

data system and factors that can change exposure (e.g., 

signifcant land use changes, trafc volume changes) have 

not occurred over the crash data period. Three years of 

data, while acceptable for identifying high-crash locations, 

is considered too unstable for identifying intersections 

with lower repetitive crash histories to be considered for 

systematic deployment of low-cost countermeasures. 

In addition, each State should defne its own threshold 

levels based upon the data analyses, a State’s ability to 

implement countermeasures, and the intersection crash 

reduction goal. 

Comprehensive Approach 

Since poor driving behavior contributes substantially to 

intersection crashes, it is important to consider initiatives 

which can improve safe driving through intersections. 

The comprehensive approach combines low-cost 

engineering countermeasures with targeted education 

and enforcement countermeasures. It is not economical 

to apply the education and enforcement components to 

a single intersection. The comprehensive approach works 

best on a corridor or within a specifc area (usually defned 

by municipality boundaries) with a signifcant number 

of severe intersection crashes. The most predominant 

driving characteristics are speeding on approaches to 

intersections (both stop-controlled and signalized) and 

red-light running at signalized intersections. To a lesser 

extent, running Stop signs and pedestrian movement 

violations may be specifc concerns for a given corridor or 

area. 

In all cases where education and enforcement initiatives 

are to be considered, appropriate low-cost engineering 

countermeasures should supplement the initiative and 

be in place before the education and enforcement 

initiatives begin. Examples of supplemental low-cost 

countermeasures include appropriate speed limit sign 

adjustments, trafc calming measures, and trafc signal 

enhancements (e.g., combined yellow plus all red 

clearance interval timing adjustments, increasing the 

visibility of the signal heads). 

The State crash data system may be used to identify 

priority corridors and municipalities with high numbers 

of intersection crashes. Those 5 to 10 mile sections of 

highway with the highest number of intersection fatalities 

and incapacitating injuries over a 5 year period would be 

candidates for corridor intersection safety improvements. 

Those municipalities with the highest number of 5-year 

intersection fatalities and incapacitating injuries (either 

total, on a per capita basis, or on a VMT basis) can be 

considered for the area-wide approach. 

Step 2 Action. 

Obtain support from the State Safety Engineer 

for the expanded approach to achieve the 

intersection crash reduction goal. 

9 
 

Step 3: 

Identify Intersection Countermeasure Types to be Considered 

Countermeasure Descriptions 

Suggested low-cost countermeasures that can be considered and the intersection conditions where these 

countermeasures can be most cost-efectively deployed are identifed in the tables below. The tables provide information 

for each countermeasure on target crash types, crash reduction factor (CRF), average expected life, and average 

construction costs. The CRF information was generated primarily from the August 2008 Federal Highway Administration 

(FHWA) Toolbox of Countermeasures and Their Potential Efectiveness to Make Intersections Safer,

1

 other recent FHWA 

publications,2 and input from intersection safety experts and practitioners. 

Systematic Approach 

The systematic approach countermeasures were developed by integrating available research fndings and input from 

intersection safety experts and practitioners in the FHWA intersection focus states.3 A more detailed description of the 

crash problem and deployment characteristics for each of the these countermeasures can be found in the FHWA report 

Low-Cost Safety Enhancements for Stop-Controlled and Signalized Intersections. 

1 http://safety.fhwa.dot.gov/tools/crf/briefs/interissuebrief.cfm 

2 FHWA-HRT-07-033, Synthesis of the Median U-Turn Intersection Treatment, Safety and Operational Benefts, http://www.tfhrc.gov/safety/pubs/07033/index.htm 

FHWA-HRT-08-053, Informational Report on Lighting Design for Midblock Crosswalks, http://www.tfhrc.gov/safety/pubs/08053/index.htm 

FHWA-HRT-08-063, Two Low-Cost Safety Concepts for Two-Way Stop-Controlled Rural Intersections on High-Speed Two-Lane, Two-Way Roadways, http://www.tfhrc. 

gov/safety/pubs/08063/index.htm 

FHWA-HRT-08-067, Trafc Calming on Main Roads Through Rural Communities, http://www.tfhrc.gov/safety/pubs/08067/index.htm 

3 The FHWA intersection focus states are a set of States with a disproportionate percent and/or number of intersection fatalities in comparison to other States. 

Suggested Mountable Curb 

Figure 3: Examples of Basic Low-Cost Countermeasures for Stop-Controlled Intersections – Double Up Oversize Warning Signs, Double Stop Signs, Trafc Island 

on Stop Approach (if feasible), Street Name Signs, Stop Bars, and Double Warning Arrow at the Stem of T-Intersections 

10 
 

 

-

Stop-Controlled Intersections 

Countermeasure 

Crash 

Reduction 

Factor 

Typical 

Urban Crash 

Threshold 

Typical 

Rural Crash 

Threshold 

Additional 

Implementation 

Factors 

Typical Imple 

mentation 

Cost Range per 

Intersection 

Basic set of sign and marking 

improvements 

40% 10 crashes 

in 5 years 

4-5 crashes 

in 5 years 

None $5,000 to $8,000 

Installation of a 6 ft. or greater raised 

divider on stop approach (installed 

separately as a supplemental counter 

measure ) 

15% 20 crashes 

in 5 years 

10 crashes 

in 5 years 

Widening required 

to install island 

$25,000 

to $75,000 

(pavement 

widening but no 

ROW required) 

Either a) fashing solar powered LED 

beacons on advance intersection 

warning signs and Stop signs or b) 

fashing overhead intersection beacons 

10% (13% for 

right angle 

crashes) 

15-20 crashes 

in 5 years 

8-10 crashes 

in 5 years 

None $5,000 to 

$15,000 

Dynamic warning sign which advises 

through trafc that a stopped vehicle 

is at the intersection and may enter the 

intersection 

Unknown 20-30 crashes 

in 5 years 

10-20 crashes 

in 5 years 

5 angle crashes in 

5 years and inadequate 

sight distance from the 

stop approach 

$10,000 to 

$25,000 

Transverse rumble strips across the stop 

approach lanes in rural areas where 

noise is not a concern and running 

Stop signs is a problem (“Stop Ahead” 

pavement marking legend if noise is 

a concern) 

28% (transverse 

rumble strips) 

15% (“Stop 

Ahead” 

pavement 

markings) 

5 running 

Stop sign 

crashes in 

5 years 

3 running 

Stop sign 

crashes in 

5 years 

Inadequate stopping 

sight distance on the 

stop approach 

$3,000 to 

$10,000 

Dynamic warning sign on the stop 

approach to advise high-speed 

approach trafc that a stopped 

condition is ahead 

Unknown 8 running Stop 

sign crashes in 

5 years 

5 running Stop 

sign crashes 

in 5 years 

Inadequate stopping 

sight distance on the 

stop approach 

$10,000 to 

$25,000 

Extension of the through edge line 

using short skip pattern may assist 

drivers to stop at the optimum point 

Unknown 10 crashes 

in 5 years 

5 crashes 

in 5 years 

Wide throat and 

observed vehicles 

stopping too far back 

from the intersection 

Less than $1,000 

Refective stripes on sign posts 

may increase attention to the sign, 

particularly at night 

Unknown 10 crashes 

in 5 years 

5 crashes 

in 5 years 

Sign visibility or 

conspicuity 

signifcantly degraded 

particularly at night 

Less than $1,000 

Table 9: Crash Reduction Factors, Typical Crash Thresholds, Additional Applications Factors, and Estimated Implementation Cost Ranges for Countermeasures at 

Stop-Controlled Intersections 

The basic set of sign and marking improvements for stop- » Doubled-up (left and right), oversize Stop signs. 

» Installation of a minimum 6 ft. wide raised splitter island on the stop 

approach (if no pavement widening is required). 

» Properly placed stop bar. 

» Removal of any foliage or parking that limits sight distance. 

» Double arrow warning sign at stem of T-intersections. 

controlled intersections referenced in Table 9 includes: 

• Low-cost countermeasures for the through approach: 

» Doubled-up (left and right), oversize advance intersection warning 

signs, with street name sign plaques. 

• Low-cost countermeasures for the stop approach: 

» Doubled-up (left and right), oversize advance “Stop Ahead” intersection warning signs. 

11 
 

Figure 3 shows the basic set of sign and marking 

improvements for stop-controlled intersections, including 

a splitter island. 

The other countermeasures in Table 9 (i.e., those not 

in the basic set of sign and marking improvements 

category) should be considered to supplement the basic 

set of sign and marking improvements at those stopcontrolled intersections (1) with higher crash frequencies 

and (2) that possess the physical characteristics that the 

countermeasure is intended to mitigate. 

Information about the J-turn treatment for stop-controlled intersections4

 is shown in Table 10. The J-turn 

treatment is to be considered primarily at high-speed, 

arterial, multi-lane highways and only permit right turn 

in and right turn out as illustrated in Figure 4. It also may 

be considered at other lower speed intersections such as 

those in urban areas. 

4 J-turn treatments are also referred to as restricted-crossing U-turn intersection 

treatments. 

Signalized Intersections 

The basic set of sign and signal enhancements referenced 

in Table 11 includes: 

• Twelve-inch LED lenses on all signal heads. 

• Back plates on all signal heads (optional refectorized border). 

• A minimum of one trafc signal head per approach lane. 

• Trafc signal yellow change interval and all-red interval timing adjusted 

to be in accordance with the Institute of Transportation Engineers (ITE) 

timing standards. 

• Elimination of any late night fashing operations. 

The basic set of sign and signal enhancements should be 

applied to all intersections with high crash frequencies. 

In addition, the other countermeasures listed in Table 11 

should be considered at signalized intersections (1) with 

higher frequencies of crashes beyond the crash threshold 

for basic countermeasures and (2) that have specifc crash 

types or physical limitations that the countermeasure is 

intended to address. 

Countermeasure Crash Reduction 

Factor 

Typical 

Urban Crash 

Threshold 

Typical 

Rural Crash 

Threshold 

Additional 

Intersection 

Concern 

Implementation 

Cost Range per 

Intersection 

J-turn modifcations on 100% cross path, 72-84% 4 angle crashes 4 angle crashes Ability to make U-turn $5,000 to 

high-speed divided arterials frontal impact, in 5 years* in 5 years* within about 1⁄4 to 1⁄2 $50,000 

43-53% all crashes mile of intersection 

* If a highway section has a series of stop-controlled intersections with a high collective number of angle crashes, it is preferable to treat the problem on a systemwide basis, addressing all of the stop-controlled intersections rather than improving a few intersections that have isolated high numbers of angle crashes. 

Table 10: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated Implementation Cost Ranges for Countermeasures at 

J-Turn Stop-Controlled Intersections 

Figure 4: Turn Restrictions at Multi-Lane Highways 

24 Total J-Turn Conflict Points 

4 Crossing 12 @ Main Intersection 

8 Weaving 10 Merge 

10 Diverge 4 @ U-Turns 

12 
Basic set of signal and 

sign improvements 

30% 20 crashes 

in 5 years 

10 crashes 

in 5 years 

None $5,000 to 

$30,000 

Change of permitted and 

protected left-turn phase 

to protected-only 

41-48% of 

left turn 

crashes 

5 left turn 

movement crashes; 

3 or more opposing 

through lanes; 

minimal turning 

gaps available 

5 left turn movement 

crashes; 3 or more 

opposing through 

lanes; minimal 

turning gaps 

available 

None $5,000 to 

$10,000 

Advance cross street 

name signs for highspeed approaches on

arterial highways 

Unknown 20 crashes in 5 

years 

10 crashes in 5 

years 

High-speed approaches on 

four or more lane arterial 

highways 

$1,000 to 

$5,000 

Advance left and right 

“Signal Ahead” warning 

signs for isolated trafc 

signals 

22% 20 crashes in 5 

years 

10 crashes in 5 

years 

Isolated trafc signal with 

one or more miles between 

signals; or trafc signals that 

are not readily visible due 

to highway alignment or 

obstructions 

$1,000 

Supplemental signal face 

per approach 

28% 20 crashes in 5 

years 

10 crashes in 5 

years 

Signal faces obstructed 

by horizontal alignment; 

or exceptionally wide 

intersections (>100 ft) where 

a near side signal is needed 

$5,000 to 

$15,000 

Advance detection 

control systems 

40% 

(injuries) 

5 angle crashes 

in 5 years 

5 angle crashes in 

5 years 

Isolated high-speed (45mph 

or greater) signalized 

intersections 

$15,000 

Signal coordination 32% 20 crashes in 

5 years per 

intersection 

10 crashes in 5 years 

per intersection 

Arterials with closely spaced 

(about 1/2 mile maximum) 

signals 

$5,000 to 

$50,000 

Pedestrian countdow

signals 

n 25% 

(pedestrian 

crashes) 

2 pedestrian 

crashes in 5 years 

2 pedestrian crashes 

in 5 years 

None $5,000 to 

$15,000 

Separate Pedestrian 

Phasing 

34% 

(pedestrian

crashes) 

2 pedestrian crashes 

in 5 years involving 

a turning vehicle 

2 pedestrian crashes 

in 5 years involving a 

turning vehicle 

None $5,000 to 

$15,000 

Pedestrian Ladder or 

cross-hatched crosswalk 

and advanced pedestrian 

warning signs 

15% 

(pedestrian 

crashes) 

for signs 

Unknown 

for 

crosswalk 

2 pedestrian 

crashes in 5 years 

2 pedestrian crashes 

in 5 years 

None $1,000 to 

$3,000 

Implemen -

tation Cost 

Range per 

Intersection 

Crash 

Reduction 

Factor 

Typical Urban 

Crash Threshold 

Typical Rural 

Crash Threshold 

Additional 

Implementation Factors Countermeasure 

Table 11: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated Implementation Cost Ranges for Countermeasures at 

Signalized Intersections 

13 
Lane narrowing using 

pavement marking and 

shoulder rumble strips 

31% 10 speed-related 

crashes in 5 years 

5 speed-related 

crashes in 5 years 

Free of noise and bicycle 

issues – single through lane 

$20,000 to 

$40,000 

Lane narrowing using 

pavement marking and 

raised pavement markers 

Unknown 

but 

probably 

less than 

10 speed-related 

crashes in 5 years 

5 speed-related 

crashes in 5 years 

Single through lane $5,000 to 

$10,000 

31% 

Peripheral Transverse 

pavement markings 

Unknown 10 speed-related 

crashes in 5 years 

5 speed-related 

crashes in 5 years 

$3,000 to 

$5,000 

Dynamic speed warning 

sign on the through 

approach to reduce speed 

30% 10 speed-related 

crashes in 5 years 

5 speed-related 

crashes in 5 years 

$10,000 

“Slow” pavement 

markings 

Unknown 10 speed-related 

crashes in 5 years 

5 speed-related 

crashes in 5 years 

$2,000 to 

$5,000 

High-Friction Surface 25% 

(All crashes) 

10 speed-related 

crashes in 5 years 

5 speed-related 

crashes in 5 years 

$20,000 to 

$50,000 

-

Both Stop-Controlled and Signalized Intersections 

Countermeasure 

Crash Reduction 

Factor 

Typical Urban 

Crash Threshold 

Typical Rural 

Crash Threshold 

Additional 

Intersection 

Concern 

Implementation 

Cost Range per 

Intersection 

New or upgraded 

Lighting 

50% (NEW), 

25% (UPGRADED) 

of night crashes 

10 night crashes in 5 years 

and a night /total crash 

ratio above the statewide 

average for urban unlit 

intersections 

5 night crashes in 5 years 

and a night/total crash 

ratio above the statewide 

average for rural unlit 

intersections 

None $5,000 to 

$15,000 

Table 12: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated Implementation Cost Ranges for Lighting Countermeasures at Unlit or Poorly Lit Intersections 

Countermeasure Crash Reduction 

Factor 

Typical Urban 

Crash Threshold 

Typical Rural 

Crash Threshold 

Additional 

Intersection 

Concern 

Implementation 

Cost Range per 

Intersection 

Skid resistant 

surface 

50% (wet pavement 

crashes only) 

8 wet pavement 

crashes in 5 years, 

a wet/total crash 

ratio above the 

statewide average 

wet/total crashes for 

intersections 

8 wet pavement 

crashes in 5 years, 

a wet/total crash 

ratio above the 

statewide average 

wet/total crashes for 

intersections 

High-speed 

approaches 

(45mph or greater) 

and a ribbed tire 

skid number of 

about 30 or less. 

$20,000 to 

$50,000 

Table 13: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated Implementation Cost Ranges for Skid Resistant 

Countermeasures at Intersections with High Rates of Low-Friction Crashes 

Countermeasure 

Crash 

Reduction 

Factor 

Typical Urban 

Crash Threshold 

Typical Rural 

Crash Threshold 

Additional 

Intersection Concern 

Implemen 

tation Cost 

Range per 

Intersection 

Table 14: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated Implementation Cost Ranges for Countermeasures at 

Stop-Controlled Intersections with High-Speed Approaches 

14 
Corridor engineering, education, and 

enforcement (3E) improvements on 

high-speed arterials with very high 

frequencies of severe intersection 

crashes 

25% of corridor

intersection 

fatal and 

incapacitating 

injury crashes 

10 or more 

intersection 

fatalities 

10 or more 

intersection 

fatalities 

Length of corridor 

should be in the 5-10 

mile range 

$1,000,000 

per corridor 

+ $100,000 

education and

enforcement 

annually per 

corridor 

Municipal-wide 3E improvements in 

municipalities with high frequencies of 

severe intersection crashes 

10% of all 

intersection 

crashes 

Top 5 or so 

municipalities 

with the most 

intersection 

fatalities 

Consider density of 

severe crashes per 

capita 

$500,000 to 

1,000,000 

+ $100,000 

to 200,000 

(dependent on 

the size of the 

city) education 

and enforcement 

annually per 

municipality 

-

Tables 11-14 provide crash reduction factors, the typical number of crash reductions, and estimated cost ranges for a 

comprehensive set of intersection countermeasures. 

Comprehensive Approach 

Automated red-light enforcement systems detect vehicles that enter a signalized intersection after the signal phase 

has turned red. The red-light camera system is connected to the trafc signal and to sensors that monitor trafc fow 

at the crosswalk or stop line. The system continuously monitors the trafc signal. For a specifed amount of time after 

the signal turns red, any vehicle entering the intersection triggers the camera. One photograph will show a readable 

license plate. A second photograph typically shows the red light violator in the intersection. Cameras record the date, 

time of day, time elapsed since the beginning of the red signal, and vehicle speed. Tickets typically are sent by mail to 

owners of violating vehicles, based on review of photographic evidence. 

Enforcement-assisted light systems activate a white light above the trafc signal as the signal turns into the red phase. 

Ofcers can be located downstream of the intersection and, using the white light activation, more easily identify and 

apprehend red light violators. 

Countermeasure 

Crash 

Reduction 

Factor 

Typical 

Urban Crash 

Threshold 

Typical 

Rural Crash 

Threshold 

Additional 

Intersection 

Concern 

Typical Imple 

mentation 

Cost Range per 

Intersection 

Table 15: Crash Reduction Factors, Default Expected Life, and Estimated Implementation Costs for Corridor and Municipal Enforcement Countermeasures 

15 
Automated red-light enforcement 25% of angle

crashes 

8 angle 

crashes in 5 

years 

4 angle crashes 

in 5 years 

Enabling legal 

authority required 

Normally $0 

if operated by 

contractor 

Enforcement-assisted lights 15% of angle 

crashes 

8 angle 

crashes in 5 

years 

4 angle crashes 

in 5 years 

Enforcement

commitment

required 

$1,000 

Countermeasure 

Crash 

Reduction

Factor 

Typical 

Urban Crash 

Threshold 

Typical 

Rural Crash 

Threshold 

Additional 

Intersection 

Concern 

Typical Imple -

mentation 

Cost Range per 

Intersection 

Table 16: Crash Reduction Factors, Typical Crash Thresholds, Additional Application Factors, and Estimated Implementation Cost Ranges for Countermeasures for 

Education-Enforcement Strategies at Signalized Intersections to Reduce Red-Light Running 

Traditional Approach 

Since the traditional approach addresses the intersections 

with the highest crash frequencies and/or severities, the 

most efective crash-reducing countermeasures should 

be considered for these intersections. These include 

roundabouts and left turn lanes. These improvements 

also are among the costliest countermeasures. Individual 

analyses are required to determine if they are the most 

appropriate improvements to implement. 

Selecting Countermeasures 

Selection of the set of countermeasures to consider for 

inclusion in the implementation plan will depend on a 

number of factors, such as: 

• The size of the crash problem that the countermeasure may impact. 

• The cost and CRF of the countermeasure. 

• Any major deployment or policy issues associated with the 

countermeasure. 

• Any legislative restrictions afecting the use or deployment of the 

countermeasure 

Table 18 provides a template for States to use when 

considering intersection countermeasures. When 

completing this template, States should include any 

additional intersection countermeasures it is using or 

considering. 

Intersections proposed for countermeasures listed 

under the frst category in Table 18 – will consider for 

widespread deployment – eventually will need feld 

inspection to verify that the countermeasure can be 

implemented and is appropriate at the intersections 

identifed. It may be appropriate to feld verify a sample 

set of intersections where the countermeasure may be 

deployed before completing the implementation plan to 

determine if deployment assumptions are acceptable. 

Countermeasures listed under the second category 

in Table 18 – will limit or restrict deployment – may 

include countermeasures with which a State has no 

or little experience (e.g., dynamic intersection warning 

sign systems at stop-controlled intersections). It may 

be appropriate to consider listing these types of 

countermeasures in the second category until further 

experience is gained. 

16 
Roundabouts 72% to 87% (injuries

and fatalities) 

Intersections 

with the most 

frequent 

severe crashes 

statewide 

Intersections 

with the most 

frequent 

severe crashes 

statewide 

Right of way 

restrictions; 

individual 

intersection analysis 

required 

$500,000 to $1 

million each 

Left Turn Lanes 13% to 24% for 

left-turn crashes 

at signalized 

intersections, 

37% to 60% for 

left-turn crashes 

at stop-controlled 

intersections 

Intersections 

with the most 

frequent 

severe crashes 

statewide 

Intersections 

with the most 

frequent 

severe crashes 

statewide 

Right of way 

restrictions; 

individual 

intersection analysis 

required 

$350,000 to 

$400,000 each 

Other Geometric Improvements 

(i.e., Elimination of Skew, 

Vertical Curve) 

Dependent 

upon type of 

countermeasure, 

see Toolbox of 

Countermeasures and Their 

Potential Efectiveness 

to Make Intersections 

Safer for specifc 

improvements 

Intersections 

with the most 

frequent 

severe crashes 

statewide 

Intersections 

with the most 

frequent 

severe crashes 

statewide 

Right of way 

restrictions; 

individual 

intersection analysis 

required 

$250,000 to $1 

million each 

Typical Imple -

mentation 

Cost Range per 

Intersection 

Typical 

Urban Crash 

Threshold 

Typical 

Rural Crash 

Threshold 

Additional 

Intersection 

Concern 

Crash Reduction 

Factor Countermeasure 

Table 17: Crash Reduction Factors, Additional Application Factors, and Estimated Implementation Costs for Traditional Approach Countermeasures 

Those countermeasures listed in the frst two categories will be helpful in developing the implementation plan. 

In addition, States should also identify reasons that 

countermeasures will not be considered (i.e., the third 

category in the template) for potential discussion among 

stakeholders during the workshop in Step 6. 

make up the set of countermeasures to consider for 

achieving the intersection crash reduction goal. For 

countermeasures that are to be limited or restricted, 

States should list the specifc issues that need to be 

addressed before wider deployment is considered. This 

17 
Systematic Approach – Stop-Controlled Intersections 

Basic set of sign and marking 

improvements 

Installation of a 6 ft. or greater raised 

divider on stop approach (installed 

separately as a supplemental 

countermeasure) 

Either a) fashing solar powered LED 

beacons on advance intersection 

warning signs and Stop signs or b) 

fashing overhead intersection beacons 

Dynamic warning sign which advises 

through trafc that a stopped vehicle 

is at the intersection and may enter the 

intersection 

Transverse rumble strips across the 

stop approach lanes in rural areas 

where noise is not a concern and 

running Stop signs is a problem (“Stop 

Ahead” pavement marking legend if 

noise is a concern) 

Dynamic warning sign on the stop 

approach to advise high-speed 

approach trafc that a stopped 

condition is ahead 

Extension of the through edge line 

using short skip pattern may assist 

drivers to stop at the optimum point 

Refective stripes on sign posts 

may increase attention to the sign, 

particularly at night 

J-turn modifcations on high-speed 

divided arterials 

Will Consider for 

Widespread CostEfective Deployment Countermeasure 

Will Limit or Restrict CostEfective Deployment Until 

Issues/Concerns are Resolved 

Will not Consider 

Deploying at This 

Time 

18 
Systematic Approach – Signalized Intersections 

Basic set of signal and sign 

improvements 

Change of permitted and protected 

left-turn phase to protected-only 

Advance cross street name signs for 

high-speed approaches on arterial 

highways 

Advance left and right “Signal Ahead” 

warning signs for isolated trafc signals 

Supplemental signal face per approach 

Advance detection control systems 

Signal coordination 

Pedestrian countdown signals 

Separate pedestrian phasing 

Pedestrian ladder or cross-hatched 

crosswalk and advanced pedestrian 

warning signs 

Will Consider for 

Countermeasure Widespread CostEfective Deployment 

Will Limit or Restrict CostEfective Deployment Until 

Issues/Concerns are Resolved 

Will not Consider 

Deploying at This 

Time 

19 
Systematic Approach – Both Stop-Controlled and Signalized Intersections 

New or upgraded lighting 

Skid resistant surface 

Lane narrowing using pavement 

marking and shoulder rumble strips 

Lane narrowing using pavement 

marking and raised pavement markers 

Peripheral transverse pavement 

markings 

Dynamic speed warning sign on the 

through approach to reduce speed 

“Slow” pavement markings 

High-friction surface 

Comprehensive Approach 

Corridor 3E improvements on 

high-speed arterials with very high 

frequencies of severe intersection 

crashes 

Municipal-wide 3E improvements in 

municipalities with high frequencies of

severe intersection crashes 

Automated red-light enforcement 

Enforcement-assisted lights 

Will Consider for Will Limit or Restrict Cost- Will not Consider 

Countermeasure Widespread Cost- Efective Deployment Until Deploying at This 

Efective Deployment Issues/Concerns are Resolved Time 

20 
Traditional Approach 

Roundabouts 

Left-turn channelization 

Other geometric improvements (i.e., 

elimination of skew, vertical curve) 

Will Consider for Will Limit or Restrict Cost- Will not Consider 

Countermeasure Widespread Cost- Efective Deployment Until Deploying at This 

Efective Deployment Issues/Concerns are Resolved Time 

Table 18: Template for Documenting Countermeasure Selection 

Step 3 Action. 

Complete Table 18 and list all the specifc 

issues that need to be addressed for all 

countermeasures identifed as limited or 

restricted. 

21 
Step 4: 

Analyze Crash and Applicable Roadway Data 

The Data Analysis Process 

The intersection safety implementation plan process is 

data-driven. The primary source of data for intersection 

crash analysis is a State’s crash data system. The data 

used in the analysis helps identify candidate intersections 

where countermeasures can be considered for costefective implementation. 

The most recent 5 years of crash data is recommended 

for use in the analysis. More years may be used if the 

data is available in the crash data system and factors that 

can change exposure (e.g., signifcant land use changes, 

trafc volume changes) have not occurred over the 

crash data period. Three years of data, while acceptable 

for identifying high-crash locations, is considered 

too unstable for identifying intersections with lower 

repetitive crash histories to be considered for systematic 

deployment of low-cost countermeasures. 

The fve levels in the data analysis process are described 

below. 

Separate Intersection Crashes into Sub-Groups 

Intersection crashes should be divided into sub-groups 

based on State or local ownership, urban or rural location, 

and trafc control type. This results in eight sub-groups for 

analysis: 

1. State rural signalized intersection crashes. 

2. State urban signalized intersection crashes. 

3. State rural stop-controlled intersection crashes. 

4. State urban stop-controlled intersection crashes. 

5. Local rural signalized intersection crashes. 

6. Local urban signalized intersection crashes. 

7. Local rural stop-controlled intersection crashes. 

8. Local urban stop-controlled intersection crashes. 

The division of crashes into State and local ownership 

is helpful since the processes for implementing similar 

improvements on the State verses the local system are 

signifcantly diferent. Crashes are separated by rural 

and urban areas because similar types of intersection 

crashes are more severe in rural areas (e.g., Table 6 shows 

that typical values for fatalities per 100 crashes for angle 

crashes are 3.53 and 0.88 for State rural and State urban 

intersections, respectively). This is important if the State’s 

goal is to reduce fatalities and/or incapacitating injuries 

instead of crashes. Finally, the types of countermeasure 

will be diferent at stop-controlled intersections compared 

to signalized intersections for similar crash patterns. In 

addition, the severity of similar crashes is greater at stopcontrolled intersections than at signalized intersections. 

Determine Target Crash Types 

Based on the countermeasures selected in Step 3, States 

should identify the crash types and characteristics that 

the countermeasures are designed to impact. The typical 

types of crashes and associated countermeasures are 

shown in Table 19. This list provides the basis for analyzing 

the crash data. The combinations of crash types and subgroups represent all of the various cuts of data that can be 

used in subsequent levels of the data analysis process: 

22 
Basic set of sign and marking improvements Systematic 

Installation of a 6 ft. or greater raised divider 

on stop approach (installed separately as a 

supplemental countermeasure) 

Systematic 

Total Crashes StopControlled 

   

Either a) fashing solar powered LED beacons 

on advance intersection warning signs 

and Stop signs or b) fashing overhead 

intersection beacons 

Systematic 

Dynamic warning sign which advises 

through trafc that a stopped vehicle 

is at the intersection and may enter the 

intersection 

Systematic 

Dynamic warning sign on the stop approach 

to advise high-speed approach trafc that a 

stopped condition is ahead 

Systematic 

Roundabouts Traditional 

Other geometric improvements (i.e., 

elimination of skew, vertical curve) 

Traditional 

Total CrashesDivided Arterials StopControlled 

  J-turn modifcations on high-speed divided 

arterials 

Systematic 

Running Stop Sign 

Crashes1 

StopControlled 

    Transverse rumble strips across the stop 

approach lanes in rural areas where noise 

is not a concern and running Stop signs is a 

problem (“Stop Ahead” pavement marking 

legend if noise is a concern) 

Systematic 

Basic set of signal and sign improvements Systematic 

Total Crashes Signalized     Signal coordination Systematic 

Roundabouts Traditional 

Left-turn channelization Traditional 

Other geometric improvements (i.e., 

elimination of skew, vertical curve) 

Traditional 

Left-Turn Crashes StopControlled 

    Left-turn channelization Traditional 

Left-Turn Crashes Signalized     Change of permitted and protected left-turn 

phase to protected-only 

Systematic 

Crash Sub Group 

Crash Type Trafc 

Control 

State

Rural

State

Urban

Local

Rural

Local

Urban 

Countermeasure Approach 

-

23 
Angle Crashes - 45 

mph and greater 

Signalized   Advance detection control systems Systematic 

Angle Crashes Signalized     Automated red-light enforcement Comprehensive 

Enforcement-assisted lights Comprehensive 

Pedestrian Crashes Signalized    

Pedestrian countdown signals Systematic 

Separate pedestrian phasing Systematic 

Pedestrian ladder or cross-hatched crosswalk 

and advanced pedestrian warning signs 

Systematic 

Night Crashes StopControlled 

    New or upgraded lighting Systematic 

Night Crashes Signalized     New or upgraded lighting Systematic 

Wet Crashes - 45 

mph and Greater 

StopControlled 

  Skid resistant surface Systematic 

Wet Crashes - 45 

mph and Greater 

Signalized   Skid resistant surface Systematic 

Speed-Related 

Crashes 

StopControlled 

   

Lane narrowing using pavement marking 

and shoulder rumble strips 

Lane narrowing using pavement marking 

and raised pavement markers 

Peripheral transverse pavement markings 

Systematic 

Systematic 

Systematic 

Dynamic speed warning sign on the through 

approach to reduce speed 

“Slow” pavement markings 

Systematic 

Systematic 

High-friction surface Systematic 

Speed-Related 

Crashes 

Signalized    

Lane narrowing using pavement marking 

and shoulder rumble strips 

Lane narrowing using pavement marking 

and raised pavement markers 

Peripheral transverse pavement markings 

Systematic 

Systematic 

Systematic 

Dynamic speed warning sign on the through 

approach to reduce speed Systematic 

“Slow” pavement markings Systematic 

High-friction surface Systematic 

-

Crash Type 

Crash Sub Group 

Countermeasure Approach Trafc 

Control 

State

Rural

State

Urban

Local

Rural

Local

Urban 

24 
-

State

Rural

State

Urban

Local

Rural

Local

Urban 

Fatal and 

Incapacitating 

Injury Crashes – 

Corridors 

N/A - Crashes are grouped by county 

and route 

Corridor 3E improvements on high-speed 

arterials with very high frequencies of severe 

intersection crashes 

Comprehensive 

Fatal and 

Incapacitating 

Injury Crashes – 

Municipalities 

N/A – Crashes are grouped by city/ 

municipality 

Municipal-wide 3E improvements in 

municipalities with high frequencies of 

severe intersection crashes 

Comprehensive 

Angle Crashes – 

Municipalities 

Signalized N/A – Crashes are 

grouped by city/ 

municipality 

Municipal-wide 3E improvements in 

municipalities with high frequencies of 

severe intersection crashes 

Comprehensive 

Pedestrian Crashes

– Municipalities 

N/A – Crashes are grouped by city/ 

municipality 

Municipal-wide 3E improvements in 

municipalities with high frequencies of 

severe intersection crashes 

Comprehensive 

Crash Type 

Crash Sub Group 

Countermeasure Approach Trafc 

Control 

1 Running Stop sign crash types may be identifed from crash data systems where this specifc type of crash in included in the data, 

usually as a causation factor. 

Table 19: Typical Types of Crashes and Associated Countermeasures 

There are a number of special cases or supplementary 

countermeasures that do not appear in Table 19 because 

they will be deployed only if an intersection warrants 

them. This determination cannot be made from the 

data; it requires feld evaluation. These special case/ 

supplementary countermeasures include: 

• Stop-Controlled Intersections: 

» Extension of the through edge line using short skip pattern may assist 

drivers to stop at the optimum point. 

» Refective stripes on sign posts may increase attention to the sign, 

particularly at night. 

• Signalized Intersections: 

» Advance cross street name signs for high-speed approaches on arterial 

highways. 

» Advance left and right “Signal Ahead” warning signs for isolated trafc 

signals. 

» Supplemental signal face per approach. 

Calculate Average Crash Costs and Crash 

Severities 

Using the countermeasures selected in Step 3 and the 

related information in Table 19, States should calculate 

the average crash costs and severity of crashes for each 

crash type/sub-group (i.e., State and local ownership, rural 

and urban area, and trafc control type) combination. The 

formula for average crash costs uses the cost data in Table 

4 and the number of injury types for each crash type/subgroup combination: 

25 
(K x 5,800,000) + (A x 402,000) + (B x 80,000) + (C x 42,000) + (PDO x 4,000) AverageCrashCost = Total Crashes 

Severity usually is measured in terms of fatalities per 100 crashes and incapacitating injuries per 100 crashes using 5 

years of data. Thus, if implementation of a given countermeasure is expected to prevent 200 crashes in a specifed 

subgroup with a severity of 1 fatality per 100 crashes, it can be expected that 2 fatalities can be prevented through the 

implementation of the countermeasures at the identifed number of intersections.1 Table 20 shows an example of a 

severity and average crash cost report for angle crashes at signalized intersections. 

Fatalities 

per 100 

Crashes 

Total 

Incapacitating 

Injuries 

Incapacitating

Injuries per 100

Crashes 

Total 

Crashes 

Total 

Fatalities 

Average Crash 

Cost Locality 

State Roads 

Rural 1,588 11 0.69 148 9.32 $89,779.60 

Urban 

Total 

27,278 

28,866 

66 

77 

0.24 

0.27 

1,520 

1,668 

5.57 

5.78 

$56,565.07 

$58,392.30 

Local Roads 

Rural 

Urban 

Total 

238 

31,643 

31,881 

5 

86 

91 

2.10 

0.27 

0.29 

5 

1,323 

1,328 

2.10 

4.18 

4.17 

$121,436.97 

$51,009.77 

$51,535.52 

Table 20: Angle Crashes – Signalized Intersections – 5 Years of Data 

Determine Distribution of Crash Densities 

Using the same list of crash type/sub-group combinations as in the average crash cost and crash severity analysis, States 

need to determine the distribution of crash densities across intersections. The frst step in this process creates a standard 

location defnition for each intersection. On State roads, this defnition typically is a combination of county, route, and 

milepost. For local roads, county, city, and the two intersecting road names are often used. The second step is to group 

crashes by intersection, so that the number of crashes per intersection can be obtained. Table 21 shows a sample, 

partial listing of crashes per intersection. It should be noted that there are over 10,000 intersections included in the 

complete listing of intersections associated with this sample. 

1 The expected number of fatalities prevented is the expected number of crashes prevented (200) multiplied by the fatalities per 100 crashes (1), or 200x(1/100) = 

200x0.01 = 2. 

26 
The fnal step is to create a summarized frequency 

distribution of intersections based on their number of 

crashes. Table 22 shows an example distribution for State, 

rural, stop-controlled intersections. This data corresponds 

with that shown in Table 21. This example shows that 

almost 5 percent2 of the intersections (i.e., those with 10 

or more crashes) account for approximately 30 percent3 of 

all the crashes at State, rural, stop-controlled intersections 

over 5 years. 

It is to be noted that only those intersections with at least 

one crash within the overall crash data period are listed. 

Therefore, there are more actual intersections in existence 

than those listed from the crash data. 

Prepare Data Analysis Package 

States should prepare a data analysis package to develop 

the straw man outline including a set of countermeasures, 

deployment level, costs, and estimated statewide annual 

crash reductions (Step 5), to provide relevant intersection 

crash information during the workshop (Step 6), and to 

develop the draft intersection safety implementation plan 

(Step 7). The package should include at least the following 

information: 

1. A comparison of annual intersection fatalities reported from the State 

crash data systems with the Fatality Analysis Reporting System (FARS) 

data for the State. 

2. A universal table showing crashes and percentages of intersection 

crashes, incapacitating injuries, and fatalities for each of the eight subgroups over 5 years of data. 

2 Almost 5 percent is calculated by dividing the number of intersections 

with 10 or more crashes (513) by the total number of intersections (10,653), or 

513/10,653 = 0.482. 

3 Approximately 30 percent is calculated by dividing the number of crashes 

at intersections with 10 or more crashes (8,601) by the total number of crashes 

(30,232), or 8,601/30,232 = 0.2845. 

Intersection 

Number 

Number of 

Crashes Percent of Total 

484482 88 0.29 

308460 77 0.25 

381451 58 0.19 

406090 55 0.18 

109723 50 0.17 

352859 50 0.17 

401778 50 0.17 

323215 47 0.16 

611052 47 0.16 

378049 45 0.15 

329718 42 0.14 

411137 42 0.14 

89587 41 0.14 

176793 39 0.13 

383587 39 0.13 

517467 39 0.13 

383490 38 0.13 

494698 38 0.13 

544656 38 0.13 

132752 37 0.12 

Table 21: Sample Listing of Crashes per Intersection – State, Rural, StopControlled Intersections – 5 Years of Data 

27 
 

Number of 

Crashes per 

Intersection 

Cumulative 

50 and greater 

30-49 

20-29 

7 

26 

91 

7 

33 

124 

0.07 

0.31 

1.16 

428 

1,390 

3,506 

1.42 

4.60 

11.60 

5-9 

10-19 

4 

3 

2 

1 

389 

1,033 

513 

1,546 

4.82 

19.92 

8,601 

15,347 

28.45 

50.76 

576 

1,008

2,034 

5,489 

Total 

2,122 

3,130 

5,164 

10,653 

10,653 10,653 100.00 

100.00 

48.47 

29.38 

14.51 

17,651 

20,675 

24,743 

30,232 

30,232 

58.39 

68.39 

81.84 

100.00 

100.00 

Number of 

Intersections Intersections Percent 

Cumulative 

Crashes Percent 

Table 22: Summarized Frequency Distribution – State, Rural, Stop-Controlled Intersections – 5 Years of Data 

3. Other general intersection crash data, such as the distribution of crash 

and injury types by speed limit for stop-controlled and signalized 

intersections and the distribution of crash types by the eight sub-groups 

(total crashes and fatalities). 

4. Sets of tables providing information on the average cost; number of 

crashes, incapacitating injuries, and fatalities; and the proportion of 

incapacitating injuries and fatalities per 100 crashes for each of the crash 

type and trafc control combinations in Table 19 that correspond to the 

countermeasures selected in Step 3. Table 20 provides an example. 

5. Sets of tables providing information on the distribution of crash densities 

by intersection for each of the crash type and trafc control combinations 

in Table 19 that correspond to the countermeasures selected in Step 3. 

Table 22 provides an example. 

An example data analysis package and straw man outline 

can be found on the FHWA Intersection Safety web page 

(http://safety.fhwa.dot.gov/intersection/resources/). 

Data Problems and Solutions 

A State may encounter at least four types of problems 

while analyzing its crash data to apply a systematic 

approach: data quality, data availability, exposure and 

rates, and intersections with multiple countermeasures. 

Approaches to addressing these problems have been 

found as discussed below. 

Data Quality 

Inconsistency of the Rural/Urban Designation at the 

Same Intersection. The rural/urban diferential is used 

to defne the probable severity of similar crashes. On 

the whole, crashes in rural areas are much more severe 

than similar types of crashes in urban areas. The rural/ 

urban designation for a crash can come from two sources: 

directly from the police crash report or transferred from 

the State’s roadway data fle. If the information comes 

28 
 

from the roadway data fle, it is consistent for all crashes 

that occur at a specifc intersection. If the information 

comes from the police crash report, the rural/urban 

designation may difer among crash reports for the 

same intersection. This becomes a problem when the 

data are grouped according to rural/urban designation. 

If an intersection has 20 crashes total, but the police 

crash reports show 13 of these in urban areas and 7 in 

rural areas, the intersection will appear on both the rural 

intersection reports and the urban intersection reports 

(i.e., an urban intersection with 13 crashes and a rural 

intersection with 7 crashes). 

The preferred solution is to link the crash and roadway 

data fles and use the rural/urban designation from 

the roadway data fle for each crash. If the rural/urban 

information is not available from the roadway fle or 

cannot be transferred, then the State should identify the 

level of data inconsistency to determine if an informed 

estimate of the correct urban/rural designation can 

be made. This can be accomplished by tabulating the 

distribution of crashes at high-crash intersections above 

the threshold level by urban and rural areas to determine 

if one type of area is predominant. Table 23 provides an 

example tabulation. 

In this case, 8 of the 10 intersections are most likely 

rural. Two of the 10 intersections (Intersections C and 

D) are too close to call. The urban/rural designation for 

crashes at Intersections C and D should be determined 

by consulting designation information from the roadway 

data fle and correcting the urban/rural data in the crash 

fles for the appropriate crashes. 

Police-reported speed limit information may be used as 

an alternate source of crash severity diferences, as it often 

has more report consistency than police-reported rural/ 

urban designation. A speed limit at and above 45 mph 

provides a breakpoint where the speed limit data for the 

same intersection is consistent. In addition, similar crashes 

at intersections where the speed limit is 45 mph or greater 

have been found to have signifcantly higher fatality rates 

(e.g., fatalities per 100 crashes) than similar crashes that 

occur at intersections where the speed limit is 40 mph 

or lower. States that do not have accurate and consistent 

urban/rural crash data elements can use speed limits as 

an indicator of intersections with higher approach speeds 

and more severe crashes similar to those experienced in 

rural areas. 

Inconsistency of the Trafc Control Device 

Information at the Same Intersection. Most States 

do not have a computerized trafc control device 

inventory. Information on the type of trafc control at 

the intersection must come from police-reported trafc 

control device information on the crash report. Almost 

all intersections are controlled by a Stop sign or a trafc 

signal. However, the type of trafc control device reported 

on the police report can vary widely and include warning 

signs, pavement markings, or no trafc control devices 

Intersection Urban Crashes 

Intersection A 22 10 32 

Intersection B 13 4 17 

Intersection C 6 5 11 

Intersection D 4 3 7 

Intersection E 6 2 8 

Intersection F 8 2 10 

Intersection G 4 1 5 

Intersection H 7 2 9 

Intersection I 5 1 6 

Intersection J 6 0 6 

Rural Crashes Total Crashes 

Table 23: Example Distribution of Crashes by Intersection – Rural/Urban 

29 
 

at all. The trafc control device information is critical 

to the implementation plan. It relates to the probable 

severity of future crashes and the type of countermeasure 

to apply to reduce future crashes. The trafc control 

device consistency problem is similar to the rural/urban 

designation problem. 

Like the rural/urban designation problem, when the 

data is grouped by trafc control device, an intersection 

could appear on more than one data report. For example, 

an intersection with 20 crashes and inconsistent and/ 

or incorrect identifcation of trafc control devices could 

appear on a stop-controlled report (assuming 10 crashes 

were identifed as stop-controlled), a signalized report 

(assuming 4 crashes were identifed as signalized), and an 

unknown report (assuming 6 crashes were identifed as 

no, other, or unknown trafc control device). 

If a State is developing a computerized trafc control 

device inventory, or at least a trafc signal inventory 

(i.e., all non-signalized intersections can be assumed 

to be stop-controlled), the State should complete the 

development of that inventory prior to the data analysis 

described here and use that inventory to determine if an 

intersection is signalized or stop-controlled. 

If a trafc control device inventory is not near completion 

or is not readily available, the overall accuracy of the 

police-reported trafc control device information should 

determine the course of action. The thresholds for 

crashes at stop-controlled intersections considered for 

countermeasure improvement are generally 5 for rural 

intersections and 10 for urban intersections. If about 

70 percent or more of total intersection crash reports 

have a correctly identifed trafc control device, then 

those intersections with a number of crashes equaling 

or exceeding the thresholds noted above (which are 

the minimum used) should have sufcient numbers of 

correctly identifed trafc control devices to predict the 

type of trafc control device for all crashes occurring 

at those intersections.4 A State can proceed toward 

implementation plan development using the predicted 

trafc control device values. If the percentage of correctly 

identifed trafc control devices is not sufcient to predict 

the type of trafc control devices at intersections with 

crashes above the threshold levels, then States should use 

a secondary source to determine trafc control devices at 

these intersections, preferably prior to the development of 

the straw man outline (Step 5). Video logs, photo logs, or 

feld reviews can be used to determine or verify the type 

of trafc control device. 

Inconsistency of Lit/Unlit Information at Intersections 

with Night Crashes. The data from police crash reports 

on the time period of the crash (e.g., day, dusk, dawn, 

night) is generally very good. However, in most States the 

data on night crashes identifying whether the intersection 

is lit or unlit have a signifcant amount of variability 

for crashes at the same intersection. Compounding 

the problem are intersections that are inadequately lit 

compared to current standards. 

To address this problem, States can identify intersections 

with a high frequency and proportion (e.g., night/total 

crashes) of night crashes. Table 24 shows an example of 

the distribution of night crashes by intersection in rural 

areas. 

States should identify the statewide mean proportion of 

night crashes to total crashes for both rural and urban 

areas. For example, with a statewide mean of 18 percent 

of night to total crashes in rural areas, those intersections 

that have both a high frequency and proportion of 

night crashes substantially above the mean (i.e., in this 

case, 25 percent or more night/total ratio) have been 

identifed in Table 24 and should be considered for some 

type of lighting enhancement. A feld review of these 

intersections is necessary to determine if lighting exists 

and if so, to what degree. 

4 By assessing the distribution of trafc control devices for crashes at the same 

intersection using the same process as described for the rural/urban designation problem. For example, if there were six crashes at a rural intersection with 

three crashes indicating a stop-controlled trafc control device, one indicating 

a signalized trafc control device, and two indicating no trafc control device, it 

can be reasonably assumed that the intersection is stop-controlled. 

30 
31 

Intersection Information for Crashes at LocallyOwned Intersections. Crash reports for crashes that 

occur at locally-owned intersections usually have reliable 

information on the county and municipality in which the 

crash occurred. However, information on the intersecting 

streets can be characterized in diferent ways depending 

on the reporting ofcer. For example, Fifth Street could be 

identifed as Fifth St., Fifth Str, 5th Street, or 5th St, among 

other variations. A standard term of “Fifth St” would 

address this issue. Unless the information is standardized, 

crashes that occur at the same intersection may be spread 

over many intersection identifers when an analyst tries to 

group crashes by intersection. This can create signifcant 

problems when trying to identify intersections with crash 

levels above a threshold. 

To address this issue, States could establish standard 

nomenclature to consolidate some of the crashes for 

local intersections. Ideally States should do this at the 

time data is entered into the crash data system. However 

if standard nomenclature is not pre-established, it can 

be selectively applied to those municipalities in which 

intersection safety initiatives are being considered during 

development of the intersection safety implementation 

plan, thus reducing the level of efort. A sample listing of 

common terms, currently being used by Arizona, includes: 

• Alley – AL 

• Avenue – AV 

• Boulevard – BLVD 

• Circle – CIR 

• Court – CT 

• Drive – DR 

• Expressway – EXWY 

• Freeway – FRWY 

• Highway – HWY 

• Road – RD 

• Street – ST 

Intersection 

Number Total Crashes 

4118 28 105 26.67% 

3814 

4017 

23 

21 

144 

176 

15.97% 

11.93% 

3332 19 31 61.29% 

5008 19 23 82.61% 

3804 18 80 22.50% 

6398 16 49 32.65% 

8958 15 41 36.59% 

1127 

3734 

14 

13 

57 

47 

24.56% 

27.66% 

1118 12 81 14.81% 

3821 

5415 

12 

12 

90 

51 

13.33% 

23.53% 

Night Crashes Night/Total Ratio 

Table 24: Example Distribution of Night Crashes in Rural Areas by Intersection 
Data Availability 

Insufcient Information to Determine if an Approach 

Pavement Has Both an Inordinate Number and 

Proportion of Wet Pavement Crashes and a Slippery 

Surface. 

The data from police crash reports on pavement surface 

conditions (e.g., wet, dry, icy, snow covered) is usually very 

reliable. However, the physical attributes of the pavement 

that may be contributing to the inordinate number and 

proportion of wet pavement crashes often are not known. 

To address this problem, States can identify intersections 

with a high frequency and proportion (e.g., wet 

pavement/total crashes) of wet pavement crashes. Table 

25 shows an example of the distribution of wet pavement 

crashes by intersection. 

States should determine the statewide mean proportion 

of wet to total crashes for rural and urban intersections 

where the speed limit is at or above 45mph. For example, 

if the statewide mean for rural intersections with speed 

limits of 45mph or above is 16 percent, those intersections 

that have both a high frequency and proportion of wet 

pavement crashes substantially above the mean (i.e., in 

this case, 25 percent or more wet pavement/total ratio) 

have been identifed in Table 25 and should be considered 

for some type of pavement surface improvement. 

The State should conduct a skid test of the approach 

to determine if the pavement has a low coefcient of 

friction. Then the State should conduct a feld review of 

the intersection and a review of the pavement history 

to determine if other surface factors such as signifcant 

rutting (i.e., greater than 2 inches) exist in the wheel paths 

which could contribute to hydroplaning. 

Intersection 

Number Total Crashes 

492147 44 121 36.36% 

310275 42 294 14.29% 

314010 35 128 27.34% 

239541 34 272 12.50% 

135899 33 65 50.77% 

352859 32 51 62.75% 

131539 31 48 64.58% 

175700 31 70 44.29% 

132762 30 102 29.41% 

636969 

654354 

30 

30 

50 

63 

60.00% 

47.62% 

310544 

189589 

245788 

538559 

28 

27 

27 

24 

137 

169 

94 

88 

20.44% 

15.98% 

28.72% 

27.27% 

Wet Pavement Crashes Wet Pavement/Total Ratio 

Table 25: Example Distribution of Wet Pavement Crashes by Rural Intersection 

32 
 

Exposure and Rates 

Exposure for Intersections is Diferent than Highway 

Segments. Exposure at intersections is measured in 

terms of the number of entering vehicles from all of 

the intersection legs rather than VMT. A few States have 

extracted volume information from their roadway data fle 

and developed entering vehicle numbers for each of the 

completely State-owned intersections in the State. This 

information can be used to establish rates of crashes per 

million entering vehicles. However, most States only pull 

the mainline annual average daily trafc (AADT) from the 

roadway data fle and attach it to each specifc crash in 

the crash data fle. As a result, an intersection with several 

crashes over a 5-year period will have diferent levels of 

AADT if the AADT is updated over the crash history period. 

Without complex and time-consuming programming, 

it can be difcult to consolidate these diferences at the 

same intersection into single values for computing rates. 

Fortunately, the use of rates is not as critical in the 

systematic application of cost-efective, low-cost 

countermeasures compared to the traditional approach. 

There are a number of approaches to refne the number 

of intersections that should be considered for systematic 

improvement considering exposure diferences. The two 

key questions that need to be addressed are: 

1. Are there any intersections with crash frequencies slightly below the 

crash threshold established that have very low entering volume values? 

For example, if the threshold for a given countermeasure in rural areas is 

5 crashes in 5 years, are there any intersections that have only 4 crashes 

but the mainline AADT is below 1,000? 

2. Are there any intersections with crash frequencies at or slightly above 

the crash threshold level which have very high entering volume levels? 

For example, if the threshold level is 5 crashes in 5 years, are there any 

intersections that have 5 or 6 crashes and a mainline AADT exceeding 

50,000? 

If the number of through lanes or the functional 

classifcation for the mainline route in the roadway data 

fle has been linked to the crash data fle, one of these 

pieces of information can be used to establish diferent 

threshold levels, either based on the number of through 

lanes or the mainline functional classifcations. For 

example, a higher crash threshold may be established 

for stop-controlled intersections with three through 

approach lanes as opposed to an intersection with a 

single through approach lane, since the volumes and 

exposure on the three through approach lane intersection 

are much greater. 

Once threshold levels are established, assuming that 

the mainline AADT for each crash is listed in the output, 

the mainline AADT for intersections slightly below, at, 

and slightly above the crash threshold level can be 

scanned to determine which intersections to consider 

for improvement. Any very low AADT intersections 

slightly below the threshold may be added to the list of 

intersections being considered for improvement. Any 

very high AADT intersections either at or slightly above 

the threshold could be removed from improvement 

consideration. 

33 
Intersections with Multiple Countermeasures 

Developing the Intersection Safety Implementation Plan Focuses on Identifying Separate Countermeasure 

Deployments at Intersections. As a result, intersections often will appear on more than one list of countermeasures. 

For example, a rural stop-controlled intersection may be above the crash thresholds for the basic set of sign and 

marking improvements, new or upgraded lighting, and skid resistance surfaces. Grouping countermeasures together 

for the same intersection is important since that it can reduce the number of multiple feld reviews at one location. 

States can create a set of matrices for each of the eight possible intersection sub-groups (i.e., State/local, rural/urban, 

stop-controlled/signalized) to identify intersections with multiple countermeasures. Table 26 is a sample matrix. This 

table shows the number of crashes above the given threshold for a specifc countermeasure by intersection. It is created 

by combining all of the distributions of crashes by intersection, using only those intersections where the number of 

crashes exceeds the threshold for that given countermeasure. 

Intersection 

Number 

Countermeasure 

4482 

9723 

0460 

1451 

6090 

5859 

88 

50 

77 

58 

55 

50 

57 

50 

88 

50 

77 

58 

55 

50 

57 

50 

17 

16 

32 

Lighting 

SkidResistant 

Surface 

J-Turn 

(Divided) 

Sign and MarkingFlashing Beacons 

Sign and 

Marking 

(Divided) 

Sign and 

Marking 

Threshold 

= 6 Total 

Crashes 

Threshold 

= 6 Total 

Crashes 

Threshold = 20 

Total Crashes 

Threshold 

= 10 Total 

Crashes 

Threshold 

= 6 Dark 

Crashes and 

Dark/Total = 

0.20 

Threshold 

= 10 Wet 

Crashes and 

Wet/Total = 

0.18 

Table 26: Sample Matrix for State, Rural, Stop-Controlled Intersections 

Step 4 Action. 

Develop an intersection crash data analysis 

package as described in this section. Use the 

example data analysis package and straw 

man outline (found on the FHWA Intersection 

Safety web page, http://safety.fhwa.dot.gov/ 

intersection/) as a guide. 

34 
Step 5: 

Develop a Straw Man Outline 

Once the countermeasures considered acceptable by 

the State to implement are identifed (Step 3) and the 

data analysis is complete (Step 4), the State can develop 

a straw man outline to achieve the intersection crash 

reduction goal (Step 1). An example data analysis package 

and straw man outline can be found on the FHWA 

Intersection Safety web page (http://safety.fhwa.dot.gov/ 

intersection/). 

Establish Threshold Crash Levels 

The frst step in creating the straw man outline is 

establishing threshold crash levels for the intersection 

and crash types that each countermeasure is intended 

to impact. At the very least, separate thresholds should 

be calculated based on road ownership and location 

(i.e., State/local, rural/urban) such that each crash type 

may have up to four thresholds depending on where the 

crashes occur. Crash threshold levels can be established 

based on a number of factors including: 

• The level at which a countermeasure is cost-efective (B/C ratio usually 

set at 2.0 or greater). 

• The number of improvements, the unit cost of the countermeasure and 

the availability of funds per threshold level. 

• The lowest number of crashes per intersection considering exposure 

levels that may reasonably indicate a recurrent crash problem that can be 

mitigated by the countermeasure (usually not less than three crashes per 

intersection in 5 years at very low-volume intersections). 

Improvements deployed on a systematic basis have 

to be cost-efective, and a B/C analysis is used to make 

the determination. The conventional analysis uses the 

following formula to compute the B/C: 

NumberCrashes x CRF x AverageCrashCost 

B/C = 

AnnualCost 

Unlike a conventional analysis, the B/C is given or set. 

The answer one seeks is the threshold, the minimum 

number of targeted crashes per intersection needed to 

make the countermeasure cost-efective. The threshold is 

represented by the number of crashes in the conventional 

B/C formula above. 

The formula used to establish the threshold is as follows: 

AnnualCost x B / C 

T = 

CRFx AverageCrashCost 

Where: 

• T = Threshold – Minimum number of targeted crashes per intersection 

needed to make the countermeasure cost-efective. 

• Annual Cost = Annual cost of the improvement. 

» If the improvement involves a construction project, annual cost is the 

construction cost averaged over the expected life of the project. 

» If the improvement is an education or enforcement initiative, annual 

cost is the annual cost of a full year of enforcement and education. 

• B/C = A set B/C ratio used to determine the threshold number of intersection crashes. In this case, a B/C value of 2.0 may be used. 

• CRF = Estimated crash reduction factor, or efectiveness, of the strategy 

to reduce targeted crashes. It is expressed in terms of the percent of 

targeted crashes reduced. 

• Average Crash Cost = Average cost of targeted crashes using the cost 

data in Table 4 and the number of injury types for the targeted crashes. 

35 
As an example, consider a signal update for State urban 

intersections where: 

• Annual Cost = $3,000 ($30,000 averaged over 10 years). 

• B/C = 2.0. 

• CRF = 0.30. 

• Average Crash Cost = $40,000 (estimated from the distribution of fatalities, injuries, and property damage crashes for State, urban, signalized 

intersections). 

3,000 x 2.0 

T = = 0.50 

0.30 x 40,000 

This example shows that the threshold should be 0.50 

crashes annually, or between 2 and 3 crashes in 5 years. 

The results indicate that it does not take many crashes 

to apply low-cost countermeasures cost-efectively. 

However, when considering scarce resources, two 

additional factors need to be considered: 

• Establishing a very low crash threshold (e.g., less than 5 crashes in 5 

years) may increase the randomness of crash occurrence and not refect 

intersections with persistent and repetitive crash occurrences. It is suggested that a minimum of fve targeted crashes in 5 years be the base 

threshold used in the analyses for most intersections. Intersections with 

four or even possibly three crashes in 5 years may be selectively added to 

the list if the trafc volumes (exposure) are extremely low. 

• Considering the relationship of crashes per intersection, number of 

intersections, and number of statewide crashes, as higher thresholds are 

set (crashes per intersection), the B/C will be larger and the total costs 

will be smaller, but the overall crash reduction also will be smaller. 

As a result, scarce resources and achieving the intersection 

crash reduction goal have to be balanced. 

Table 27 shows a sample distribution of crashes at State, 

urban, signalized intersections. If a State starts at the base 

level to achieve a B/C of 2.0 or greater (i.e., 3 or more 

crashes per intersection), then 2,955 intersections would 

be improved. This would encompass 97.5 percent of 

all signalized intersection crashes. However at $30,000 

per intersection improvement, the costs to improve all 

2,955 intersections would be close to $90 million. If the 

threshold is increased to 5 crashes per intersection, 2,487 

intersections would be improved, encompassing 95.3 

percent of all State urban signalized crashes. The costs for 

this level of improvement would be close to $75 million. 

Assuming funds are not that plentiful, if a threshold 

level of 50 crashes per intersection is selected, only 371 

intersections would need to be improved at a cost of 

about $10 million. This would still encompass over 38 

percent of all State, urban, signalized crashes. 

Number of 

Crashes per 

Intersection 

Cumulative 

100 and greater 63 63 1.44 8,058 10.90 

50-99 308 371 8.46 28,570 38.65 

30-49 461 832 18.98 46,320 62.67 

20-29 483 1,315 30.00 57,986 78.45 

10-19 633 1,948 44.43 66,850 90.44 

5-9 539 2,487 56.73 70,471 95.34 

4 206 2,693 61.43 71,295 96.46 

3 262 2,955 67.40 72,081 97.52 

2 403 3,358 76.60 72,887 98.61 

1 1,026 4,384 100.00 73,913 100.00

Total 4,384 4,384 100.00 73,913 100.00 

Number of 

Intersections Intersections Percent 

Cumulative 

Crashes Percent 

Table 27: Sample Distribution of Crashes at State Urban Signalized Intersections 

36 
Basic Set of Sign and 

Marking Improvements 

– State Rural StopControlled Intersections 

Basic Set of Sign and 

Marking Improvements 

– State Urban StopControlled Intersections 

Total 1,356 10.85 14.38 

379 

977 

23,795 

13,722 

474 

1,221 

30 

6 

2.67 

11.71 

3.03 

7.82 

0.21 

1.60 

1,269 

732 

Develop Detailed Straw Man Tables 

for Each Countermeasure 

The straw man consists of a set of countermeasures, 

deployment levels, costs, and safety impacts (usually 

defned in terms of the overall goal (i.e. annual lives 

saved), which collectively can achieve the overall 

intersection safety goal. Each countermeasure needs to 

be investigated in terms of its deployment levels, costs, 

safety impacts, and relative contribution in achieving the 

overall intersection safety goal using data from the data 

analysis. An example of the tabulation of intersections that 

can be considered for the basic set of sign and marking 

improvements for State stop-controlled intersections is 

shown in Table 28.1 In this table, 1,221 intersections had 6 

or more crashes within the crash history period. A 6-year 

crash history period was used in this evaluation because it 

was available and provided more stable data than 5 years 

of data. In addition, no signifcant changes in trafc or 

roadway features occurred during the 6 years. 

1 The full example data analysis package and straw man outline can be found 

on the FHWA Intersection Safety web page (http://safety.fhwa.dot.gov/intersection/). 

Not all of the intersections shown in Table 28 will end 

up as improvements. Some will have been upgraded 

previously; feld reviews of others will show that sign 

and marking enhancements do not make sense. In 

this case, an assumption is made that only 80 percent 

of the intersections will remain candidates for the sign 

and marking enhancements after the feld review. Each 

State can establish its own estimated retention rate for 

the improvement estimate. If time is available, a more 

accurate means of developing the estimate is to feld 

review a random sample of the candidate intersections 

beforehand and use the percentage of these intersections 

in which enhancements are likely for the estimate. 

A trial and error method can be used to develop the 

straw man outline with an objective to achieve the 

intersection crash reduction goal with the least costs. Each 

of the accepted countermeasures can be deployed at 

levels dependent on the distribution of crashes, severity 

of crashes (fatalities per 100 crashes), CRF, and unit 

construction costs. The annual lives saved per $1 million 

expended can be used as a gauge to determine what 

levels are appropriate for each countermeasure. 

ash

ears) 

hreshold Cr

(6 Yel veL

T

Countermeasure 

Number of

Statewide Crash

Intersections

Number of

ear6 Yed getar

Crashes in the

tionstersecnI

T

1 ts

edEstimat

Number of

vemenomprI

2

tion

illion)

Construc

Costs ($ M

ashesCr

atalities per 100F

ash

3 

nnual

ed Cr

tion

A

getar

Reduc

T

4 

nnual

ed

y

A

Estimat

tion

talitaF

Reduc

1 Estimated number of improvements assumes that 80 percent of locations can be improved. Estimated number of improvements is calculated by 

multiplying the number of statewide crash intersections by the percent of locations that can be improved. For the frst row of the table, this calculation is 

1,221x0.80 = 977. 

2 Construction costs assume an average cost of $8,000 per intersection. Construction costs are calculated by multiplying the estimated number of 

improvements by the average cost per intersection. For the frst row of the table, this calculation is 977x8,000 = $7.82 million. 

3 Annual targeted crash reduction uses a CRF of 0.40. Annual targeted crash reduction is calculated by multiplying the average number of targeted 

crashes per year by the percent of locations that can be improved multiplied by the CRF. For the frst row of the table, this calculation is (13,722/6) 

x0.80x0.40 = 732. 

4 Annual estimated fatality reduction is calculated by multiplying the annual targeted crash reduction by the fatalities per 100 crashes and dividing by 

100. For the frst row of the table, this calculation is (732x1.6)/100 = 11.71. 

Table 28: Sample State Stop-Controlled Intersections - Basic Set of Sign and Marking Improvements 

37 
Compile a Summary Straw Man 

Outline 

After all of the individual countermeasure detailed 

straw man tables are created, the State should develop 

a summary straw man outline. The summary straw 

man outline should encompass all of the candidate 

countermeasures, the impact toward achieving the 

overall statewide intersection goal, and the costs of 

improvements. Specifc elements include the following: 

• Countermeasures – All of the countermeasures selected in Step 3. 

• Approach – Systematic, comprehensive, or traditional. 

• Number of Statewide Crash Intersections to be Improved – Number of 

intersections with the crash characteristics that can be impacted by the 

countermeasure. Transferred from the detailed straw man tables. 

• Construction Cost – Cost for construction of infrastructure countermeasures. Transferred from the detailed straw man tables, as applicable. 

• Enforcement and Education Costs – Costs for enforcement and education, 

countermeasures. Transferred from the detailed straw man tables, as 

applicable. 

• Estimated Annual Crashes Reduced – Number of crashes reduced annually. Transferred from the detailed straw man tables. 

• Estimated Annual Incapacitating Injuries Reduced – Number of incapacitating injuries reduced annually. Transferred from the detailed straw man 

tables, as applicable. 

• Estimated Annual Fatalities Reduced – Number of fatalities reduced 

annually. Transferred from the detailed straw man tables. 

Table 29 shows an example of a summary straw man 

outline. It is based on a State that established a goal to 

reduce intersection fatalities by 28 per year by 2012. 

In this example, the State chose to focus on reducing 

both fatalities and incapacitating injuries. As a result, the 

estimated annual incapacitating injuries reduced column 

is included. In addition, only the countermeasures that the 

State agreed to implement are included in the table (i.e., 

other countermeasures are not listed because the State 

decided not to include them in the intersection safety 

implementation plan). 

38 
Basic Set of Sign and 

Marking Improvements 

– State Stop-Controlled 

Intersections (Rural and 

Urban) 

Systematic 1,108 8.87 1,382 117.7 13.07 

Flashing Overhead 

Intersection Beacons – 

State Stop-Controlled 

Intersections (Rural and 

Urban) 

Systematic 69 0.69 54 4.0 0.44 

J-Turns Modifcations 

on High-Speed Divided 

Arterials – State Rural 

Stop-Controlled 

Intersections 

Systematic 56 16.80 77 17.5 2.87 

Basic Set of Sign and 

Marking Improvements 

– Local Stop-Controlled 

Intersections (Rural and 

Urban) 

Systematic 236 1.89 555 15.1 0.71

Basic Set of Signal and 

Sign Improvements 

– State Signalized 

Intersections (Rural and 

Urban) 

Systematic 395 1.92 789 28.1 1.52 

Basic Set of Signal and 

Sign Improvements 

– Local Signalized 

Intersections (Rural and 

Urban) 

Systematic 263 2.63 670 19.5 1.51 

Change of Permitted 

and Protected Left-Turn 

Phase to Protected 

Only – State Signalized 

Intersections (Rural and 

Urban) 

Systematic 536 2.67 819 44.0 1.49 

Change of Permitted 

and Protected Left-Turn 

Phase to Protected 

Only – Local Signalized 

Intersections (Rural and 

Urban) 

Systematic 387 1.94 623 23.7 1.27 

Advanced Detection 

Control Systems– State 

Signalized Intersections 

(Rural and Urban) 

Systematic 67 1.00 45 4.2 0.31 

Countermeasure 

oach pprA

o

Number of

tions t

edvo

tersec

mpr

n

be I

I

tionConstruc

osts

illion)

C

($ M

,tcemenor

ation and

osts

Enf

duc

EMS C

Annual $(

Thousand)

E

edEstimat

ashes

ed

Annual Cr

Reduc

ed

ed

ting

Estimat

nnualA

apacitancI

njuries ReducI

edEstimat

Annual Fatalities

ed Reduc

39 
New or Upgraded 

Lighting – State 

Rural Intersections 

(Stop-Controlled and 

Signalized) 

Systematic 64 3.84 49 8.4 1.08 

Systematic 53 2.65 86 11.3 1.27 

Systematic 1 City 0.09 45 2.3 0.11 

Comprehensive 3 Corridors 6.00 83 7.5 1.25 

1 City 1.00 383 6.6 0.57 

3 2.40 32 3.0 0.36 

54.39 5,692 312.9 27.83 

Comprehensive 

0.05 

0.30 

0.10 

0.45 

Traditional 

High-Friction Surface 

– State Intersections 

(Stop-Controlled and 

Signalized, Rural and 

Urban) 

Enforcement-Assisted 

Lights 

Corridor 3E 

improvements on 

high-speed arterials with 

very high frequencies 

of severe intersection 

crashes 

Municipal-wide 3E 

improvements in 

municipalities with high 

frequencies of severe 

intersection crashes 

Roundabouts 

Total 

Approach 

Countermeasure 

Number of

Intersections to

be Improved

Construction

Costs

($ Million)

Enforcement,

Education and

EMS Costs

(Annual $

Thousand)

Estimated

Annual Crashes

Reduced

Estimated

Annual

Incapacitating

Injuries Reduced

Estimated

Annual Fatalities

Reduced 

Table 29: Sample Summary Straw Man 

Step 5 Action. 

Using the intersection crash data analysis 

package from Step 4, establish threshold crash 

levels, develop detailed straw man tables for 

each countermeasure, and compile a summary 

straw man outline. Use the example data 

analysis package and straw man outline (found 

on the FHWA Intersection Safety web page, 

http://safety.fhwa.dot.gov/intersection/) as a 

guide. 

40 
Step 6: 

Conduct a Workshop of Key Stakeholders and Follow-Up Implementation Planning 

Meeting 

Two-Day Workshop 

The successful reduction in statewide intersection 

fatalities and incapacitating injuries requires the 

input, support, and participation of a number of key 

stakeholders. They include at least the following: 

• State Safety Engineer. 

• State Trafc Engineer. 

• State Trafc Signal and Trafc Operations Engineers. 

• District or Regional Trafc/Safety Engineers. 

• State Local Roads Coordinator (if one exists). 

• Governor’s Highway Safety Representative. 

• Representatives of local governments (e.g., city, county trafc safety 

representatives). 

• State and local police representatives. 

• Metropolitan planning organization (MPO) representatives. 

• FHWA Division Ofce Safety Engineer/Specialist. 

The State should conduct a workshop with key 

stakeholders to achieve three goals: 

1. Discuss the intersection crash reduction goal, the systematic and comprehensive approaches to achieve the goal, the crash data analysis package, 

and the use of potentially new intersection countermeasures. 

2. Reach group consensus on a set of countermeasures, deployment characteristics, and costs to achieve the intersection crash reduction goal. 

3. Establish strategic directions to successfully implement the countermeasures. 

In preparation for the workshop, the following information 

should be prepared for discussion: 

• A statewide intersection crash reduction goal. 

• A set of intersection countermeasures that the State is comfortable 

implementing and estimated unit costs and crash reduction factors for 

each countermeasure. 

• An intersection crash data analysis package that supports development 

of the straw man outline. 

• A straw man outline of countermeasures; deployment levels; and characteristics, costs, and projected annual crashes, incapacitating injuries, and 

fatalities reduced for each countermeasure which collectively is sufcient 

to achieve the intersection crash reduction goal. 

A typical agenda for the workshop is shown in Table 30. 

41 
Workshop Agenda 

8:30 AM 

Day 1 

Welcome and Introductions 

• Review of Workshop Goals, Objectives, and Outcomes 

• Background on Reducing Intersection Fatalities 

8:45 AM Module I: Intersection Goal, Data Analysis, and Countermeasure Identifcation 

10:15 AM Module I Continued 

1:00 PM Module II: Putting It All Together 

2:45 PM Break 

3:00 PM Module II Continued 

• Straw Man Outline of Countermeasures, Deployment Characteristics, Costs, and Lives Saved 

8:30 AM 

Day 2 

Module II Reality Check 

• Review Day 1 Results 

• Review and Fine-Tune Straw Man Outline 

• Check Personal Knowledge of High-Crash Intersections to Determine if Improvement Types Make Sense 

9:45 AM Break 

10:00 AM 

12:00 PM Lunch 

1:00 PM Module III Continued 

2:00 PM 

3:00 PM Module V: Next Steps 

3:15 PM Adjourn 

Table 30: Typical Agenda for Intersection Safety Implementation Plan Workshop 

42 

10:00 AM Break 

12:00 PM Lunch 

4:30 PM Adjourn 

Module III: Strategic Direction and Actions 

• Crosscutting Barriers 

• Key Countermeasure Barriers 

Module IV: Action Items to Implement Components of the Plan 

• Key Steps to Implement Countermeasures 

• Performance Measures 

• Implementation Plan Outline 
 

On the first day it is important for the group to understand the intersection crash reduction goal, the systematic and comprehensive approaches, and how these 

approaches work together to achieve the goal. In addition, the data analysis package assembled in Step 4 and 

the list of potential intersection countermeasures created 

from Step 3 need to be discussed. The group also should 

have an introduction and initial discussion of the straw 

man outline on Day One. The group will probably suggest 

changes and refnements to the straw man outline. 

After the Day One activities are complete, the straw man 

outline should be updated to refect the changes and 

refnements. The refned straw man outline should be 

presented to the group on the morning of the second 

day. It is critical for the group to reach consensus on a 

fnal refned straw man outline that identifes the set of 

countermeasures, deployment levels, and costs required 

to achieve the intersection crash reduction goal. If 

necessary, the goal may be adjusted in terms of safety 

impact to be achieved (i.e., targeted annual lives saved) or 

time to achieve the goal. 

Once the straw man outline is complete, the group 

identifes any key issues that may impact the successful 

implementation of the efort and establishes actions and 

strategic directions to address each issue. In working 

through the agenda items, several issues may arise. These 

issues and potential solutions gleaned from previous 

workshops are discussed below. 

Insufcient Existing Funding to Achieve the Goal. 

Available Highway Safety Improvement Program 

(HSIP) resources may not be sufcient to fund all of the 

improvements in the plan. To overcome this, States can 

seek other available federal safety fund sources (e.g., 

High Risk Rural Roads program, Section 1406 – Safety 

Incentive Grants for Use of Seat Belts, Section 1407 – 

Safety Incentive to Prevent Operating of Motor Vehicles by 

Intoxicated Persons, Section 406 – Safety Belt Performance 

Grants, and Section 410 – Alcohol-Impaired Driving 

Countermeasure Incentive Grants), utilize regular Federalaid funds; or use State or local funds. The time to achieve 

the goal also may be extended, thus lowering the annual 

funding needs to an afordable level. 

Improvements at Local Intersections with Federal 

Funds. A considerable number of State and federal 

requirements impede the fow of funds to local 

governments for low-cost countermeasures. To address 

this issue, States may wish to use specially-trained Local 

Technical Assistance Program (LTAP) safety engineers 

and/or consultants with 100 percent federal funding to 

administer the program, perform the engineering, and 

oversee the implementation. States then can provide 

the materials (e.g., signs, marking material, signal 

appurtenances) to local governments using 100 percent 

federal funding as long as the localities correctly install the 

materials in the feld. This removes any transfer of funds 

between State and local governments. 

Education and Enforcement Initiatives Beyond the 

Conventional 402 Funding. States may fnd that the 

countermeasures for education and enforcement in 

corridors and municipalities require more 402 funds 

than what is available. In this case, States can investigate 

other federal safety funding sources available to the 

State (e.g., Section 1406 – Safety Incentive Grants for Use 

of Seat Belts, Section 1407 – Safety Incentive to Prevent 

Operating of Motor Vehicles by Intoxicated Persons, 

Section 406 – Safety Belt Performance Grants, and Section 

410 – Alcohol-Impaired Driving Countermeasure Incentive 

Grants). 

Use of Countermeasures New to or Rarely Used in 

the State. Any time something new is implemented, the 

potential for failure increases because of the increased 

level of unknown factors. States can minimize the 

potential for failure by taking the following actions: 

• Identify a champion, a safety professional, responsible for overseeing the 

implementation of the countermeasure. 

• Ensure that the champion becomes profcient in knowledge regarding the countermeasure by reviewing literature, conferring with other 

out-of-state professionals with extensive knowledge regarding the 

countermeasure, and potentially visiting out-of-state sites where the 

countermeasure has been deployed. 

• Seek District or Regional personnel who may be interested in deploying a 

demonstration of the technology. 

• Identify the key issues that are preventing widespread implementation 

of the countermeasure and establish scheduled demonstrations to address the issues and evaluate the results.1 

• Ensure that the champion performs a rigorous assessment of the 

demonstrations to determine if any design, construction, or operational 

changes need to be made; if the countermeasure is ready for widespread 

deployment; and if additional demonstrations are needed. 

• Upon completion of the demonstrations, make a decision on the countermeasure’s readiness for widespread deployment. If so, integrate the 

countermeasure into normal operations. If not, make a determination on 

whether the countermeasure should be considered for further deployment. If the determination is to proceed, identify the remaining issues 

and establish a process and schedule to address them. 

1 Rely on other State eforts to evaluate the countermeasure’s CRF since there 

will be insufcient data and time to properly evaluate crash reduction efectiveness within the State. 

43 
-

Countermeasures Involving Policy Decisions. At least two countermeasures may involve signifcant policy issues– 

lighting on State rural intersections and installation of enforcement-assisted lights at trafc signals to reduce red-light 

running. Existing lighting policies may limit the use of lighting to freeways. In addition, a State may not have a policy in 

place for installing on the highway system devices that can enhance enforcement. Addressing these issues likely will 

require input from upper management. 

• Lighting on State Rural Intersections – Many States have limited lighting on freeways or at interchanges and have not considered lighting at intersections because of the potential fscal impact. To minimize fscal impact, States can limit lighting consideration to only those intersections with a high 

frequency and proportion of night crashes, utilize 100 percent Federal funding for the lighting improvements, and/or consider requiring local municipalities where the intersections reside to energize and maintain the lighting. 

• Installation of Enforcement-Assisted Lights – The value of enforcement-assisted lights is dependent on how aware drivers are of the function 

of enforcement-assisted lights, an agreement by police to use the lights for red-light running enforcement, and the commitment of the courts to process 

the police citations. If drivers know that police use the lights for enforcement, they easily can see the lights as they approach an intersection and slow 

down to stop on red. This should reduce the level of red-light running signifcantly. States should consider installing enforcement-assisted lights only in 

those municipalities with an angle crash problem at signalized intersections. Within these municipalities, States should ensure that police organizations 

agree to a written commitment to use the enforcement-assisted lights to enforce red-light running violations. States must also ensure that sufcient 402 

funds are available to mount a limited education campaign for the residents of and surrounding the municipality about the purpose of the enforcementassisted lights and red-light enforcement. Alternate funding such as using the fexible funding provisions of the HSIP program or State funds can also be 

considered. 

Half-Day Follow-Up Implementation Planning Meeting 

After the workshop, on the morning of the third day, a small group of key State personnel (at least the State Safety 

Engineer, the State Trafc Engineer, and the Governor’s Highway Safety Representative) and the FHWA Division Ofce 

Safety Engineer/Specialist should meet to review the results and identify key steps needed to successfully move each 

countermeasure from its existing state to full implementation as defned in the tentative plan. A representative of local 

governments, an MPO, or the police may also participate at the discretion of the State. This small group also discusses 

strategic directions for implementing the plan and schedules for implementation, including identifying the upper 

management who must approve the initiative and the actions and schedules needed to secure that approval. 

Step 6 Action. 

Plan and conduct the two day workshop with 

key stakeholders to gain consensus on a set 

of countermeasures, deployment levels and 

characteristics, costs, and fatality reductions 

needed to achieve the intersection crash 

reduction goal. Plan and conduct the half-day 

follow-up implementation planning meeting 

to reach consensus within the State on the key 

steps and schedule to fully implement each 

countermeasure. 

44 
Step 7: 

Develop a Draft Intersection Safety Implementation Plan 

Upon completion of the workshop and follow-up meeting 

with key State personnel, the State develops a draft 

implementation plan. The plan should: 

• Establish or re-state the intersection crash reduction goal. 

• Document the problem, countermeasures, deployment characteristics, 

and funding needed to achieve the intersection crash reduction goal. 

• Identify funding levels needed to implement plan and potential funding 

sources. 

• Establish who has to approve the initiative and its funding and what is 

required for a decision. 

• Document any cross-cutting or key issues (e.g., funding, local intersection countermeasure deployment, deploying new or rarely used 

countermeasures) and how they should be addressed. 

• Document key steps and decisions needed to efectively implement the 

countermeasures in the plan and achieve the goal. 

• Establish performance measures and tracking mechanisms to monitor 

implementation and fatality reductions. 

A suggested outline for the plan is as follows: 

• Executive Summary. 

• Background. 

• The Intersection Safety Goal. 

» The Approach. 

» Distribution of the State Intersection Fatality Problem. 

» Summary of Countermeasures. 

• Key First Steps. 

• Implementation. 

» Countermeasure Descriptions. 

» Key Implementation Steps. 

• Performance Measures 

» Production Performance Measures. 

» Impact Performance Measures. 

• Performance Standards – Program Efectiveness in Reducing Targeted 

Crashes 

• Summary. 

An example intersection safety implementation plan 

is available on the FHWA Intersection Safety web page 

(http://safety.fhwa.dot.gov/intersection/). 

The draft plan should be circulated to the key 

stakeholders who participated in the workshop and 

follow-up meeting for additions, deletions, and/or 

modifcations. Once all comments are received, the plan 

should be updated into a revised draft form. 

Step 7 Action. 

Develop a draft intersection safety 

implementation plan based upon the results of 

the workshop and follow-up meeting. Circulate 

the plan among workshop and follow-up 

meeting participants. Revise the draft based on 

comments received. 

45 
 

 

 

 

Step 8: 

Present the Draft Intersection Safety Implementation Plan to Upper Management 

The draft plan is presented to upper management for 

approval, rejection, or modifcation. Upper management 

input is needed for successful implementation, since 

the plan probably will involve addressing a number 

of new issues, implementing new countermeasures, 

and increasing funding levels. These issues should be 

presented clearly to upper management for direction. 

Some of the key items in a briefng to upper management 

may include the following. 

Funding. The plan may require additional funding 

beyond that available from the HSIP. The presentation 

should include an overview of the type and level of 

projects for which the funds will be used; the expected 

impact in terms of lives saved and incapacitating injuries 

and crashes prevented; alternative sources for securing 

the additional funding; and a recommended fnancial 

approach to implement the plan. 

Approach. Reducing statewide intersection fatalities and 

incapacitating injuries likely will require supplementing 

the traditional approach with the systematic and 

comprehensive approaches. 

New Countermeasures Not or Rarely Used in the 

State. The presentation should describe the process 

for implementing the new countermeasure in a way 

that minimizes risks of failure and/or adverse publicity 

while meeting the timeframes established in the plan. 

The presentation should include a list of the new 

countermeasures and how they will be introduced and 

implemented in the State. 

Implementing Safety Improvements at LocallyOwned Intersections. The presentation should include 

an overview of the scope of the intersection crash 

problem on local intersections, the suggested course of 

action to make local municipalities aware of the problems, 

and actions the State should take to assist municipalities 

implement the improvements. A recommended 

methodology to fnance local intersection improvements, 

including the role that the State should play, should also 

be included. 

Policy-Related Actions. Some of the potential 

countermeasures (e.g., lighting rural intersections with 

high frequencies and proportions of night crashes) have 

been applied rarely or never in many States. Funding 

these improvements, including the maintenance and 

energizing responsibilities, require upper management 

direction. The presentation should identify portions of the 

plan that involve policy issues and provide recommended 

courses of action that meet the plan objectives while 

minimizing potential adverse actions on the State. 

Funding Education and Enforcement Initiatives. Some 

of the corridor or municipal-wide initiatives may require 

funding beyond existing 402 funding levels. If this occurs, 

alternate funding sources (and recommendations on their 

use) need to be presented to upper management for 

direction. This will require special coordination with the 

Governor’s Highway Safety Representative if that person is 

located outside of the State DOT. 

Step 8 Action. 

Prepare a presentation on the draft 

intersection safety implementation plan and 

its key issues for upper management group 

approval and direction. 

46 
Step 9: 

Finalize the Intersection Safety Implementation Plan 

The feedback received from upper management may 

alter some of the contents and recommendations in the 

plan. The fnal plan should incorporate these changes1 

and then be circulated to all of the key stakeholders for 

informational purposes. 

1 In most cases, this is the responsibility of the State Safety Engineer. 

Step 9 Action. 

Finalize the intersection safety implementation 

plan based upon the guidance and direction 

provided by upper management. Circulate 

the fnal plan among key stakeholders for 

informational purposes. 

47 
Step 10: 

Implement the Plan, Monitor Progress, and Evaluate Results 

Once the intersection safety implementation plan is 

fnalized, the State should take a number of key actions 

to ensure successful implementation and statewide 

reduction of intersection fatalities and incapacitating 

injuries. Suggested actions to improve the likelihood of 

success include: 

1. Create an oversight committee led by the State Safety Engineer and 

composed of at least the Governor’s Highway Safety Representative 

and the State Trafc Engineer (or their representatives) and the FHWA 

Division Ofce Safety Engineer/Specialist. The oversight committee 

should meet on a quarterly basis to monitor progress, provide direction, 

and make mid-course adjustments. The oversight committee also should 

periodically report back to upper management on progress. 

2. For each countermeasure in the plan, seek or assign a staf professional 

as coordinator to be responsible for its successful implementation. The 

coordinators should provide periodic (i.e., at least twice a year) input to 

the oversight committee on adhering to the implementation schedules 

defned in the implementation plan for each countermeasure. 

3. Develop and implement a system to track projects in the plan for each 

countermeasure for project development progress, construction, and 

crash history following construction. 

4. On a bi-annual basis, make a comprehensive review of the plan. Update 

the plan as needed to refect any substantive modifcations or signifcant 

adjustments. 

Step 10 Action. 

Conduct implementation, monitoring, and 

evaluation activities. 

48 

For More Information 

Jeffrey Shaw 

Intersections Program Manager FHWA Office 

of Safety 

202.738.7793 

jeffreyshaw@dot.gov 

U.S. Department of Transportation 

Federal Highway Administration 

FHWA-SA-10-010 Updated July 2020