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Public Roads - November/December 2004

November/December 2004
Issue No:
Vol. 68 No. 3
Publication Number:
Table of Contents

Traffic Incident Management

by David L. Helman

Clearing incidents safely and quickly requires an effective traffic incident management program 24 hours a day, 7 days a week.

(Above) Incidents like this tractor-trailer spill may involve relatively benign materials, like the trash shown here, or hazardous materials such as gas or chemicals. The cleanup of such events can be both costly and time-consuming. Photo: New Jersey DOT.

At 2:46 p.m. on January 13, 2004, a tanker truck loaded with about 30,000 liters (8,000 gallons) of gasoline went out of control on a curved elevated ramp carrying Interstate 895 over Interstate 95 in Maryland. The tractor trailer climbed the concrete barrier and plunged down onto the northbound lanes of I-95. The tanker hit another truck on I-95 below and burst into flames. Two other vehicles also were involved in the crash.

During the nearly 13-hour course of the incident and the following investigation and cleanup, more than 200 responders from over a dozen agencies and private sector companies were involved onsite, and many more were involved offsite in managing the traffic flow and providing traveler information. About 4 hours after the incident occurred, two of the four southbound lanes were reopened to traffic. By 3:35 the next morning, all lanes were opened in both directions for the morning peak period.

Although the I-95 crash is not typical of the many thousands that occur daily on the Nation's highway system, it illustrates that incidents can involve multiple responders from a variety of organizations with different responsibilities and priorities. The number of individual responders and organizations represented increases dramatically with the severity and complexity of an incident.

For most incident responders, the top priority is to rescue and remove any injured people, protect responders and the scene, minimize environmental damage, and investigate the incident quickly and thoroughly. At the same time, it is critical to provide traffic control by moving motorists through the scene and providing approaching motorists with information to make informed decisions about travel in the affected area or areas.

"Clearing incidents safely and quickly depends on developing coordinated multiagency operations that are supported by integrated communications," says Captain Henry de Vries, New York State Police. "In other words, it depends on effective traffic incident management." The importance of establishing a traffic incident management (TIM) program with transportation and public safety agencies and others cannot be overemphasized. With more than 200 responders from dozens of agencies involved in the I-95 example, the Maryland State Highway Administration attributes the speedy response to established relationships and a TIM program.

Impacts of Incidents On Safety

Traffic congestion is the most obvious result of an incident, but responders are justifiably concerned for their own safety and those involved in the crash, especially on limited access high-speed freeways. In 1997, nearly 40 percent of all law enforcement officers who perished in the line of duty died in traffic. Concern for on-scene safety leads public safety officers to close all lanes or at least some additional lanes not affected by an incident to provide a safety buffer.

Nonrecurring events, such as incidents, weather, work zones, and special events, cause more than half of all traffic congestion, according to the FHWA Office of Operations.

Approximately 20 percent of all incidents are secondary in nature. That is, they happened as the result of previous incidents. Most of these secondary incidents are minor (vehicles overheating or running out of fuel), but some are severe, resulting in deaths or serious injuries. Of special concern are nighttime incidents involving lane closures. Drivers approaching these incidents often are traveling at higher speeds due to lighter traffic conditions and do not expect to be slowed or stopped. In addition, reduced lighting makes visibility more difficult and accentuates confusion or visual blinding caused by flashing lights and strobes on emergency vehicles.

Impacts of Incidents On Traffic Congestion And Delay

Approximately 50 percent of all traffic congestion in the United States is caused by "nonrecurring" events such as traffic incidents, weather, and construction work zones. About half of this congestion (25 percent) is caused solely by traffic incidents (stalled vehicles, spilled loads, debris on the road, and crashes).

A fire truck and other emergency vehicles create a road closure following an incident in southern Virginia.
True unified command is demonstrated when police, fire, commercial vehicle enforcement, and towing representatives discuss and agree on the best and safest method to remove a propane tanker. The recovery of this tanker was completed in less than 30 minutes.

Lane-blocking incidents affect traffic flow far out of proportion to the number of lanes blocked. An incident blocking one lane out of three on a freeway reduces the capacity of that facility by approximately 50 percent. Blocking two lanes of three reduces capacity by nearly 80 percent.

Even minor lane-blocking incidents can have significant impacts on traffic if they are not removed quickly. But their impacts are accentuated during peak traffic hours. If a lane is blocked when traffic flow is at or near the capacity of a facility, the queue of traffic that accumulates behind the incident will not dissipate after the incident is removed until the traffic flow into the queue decreases—in other words, until the peak period ends. Thus a standing queue of traffic may exist for several hours, depending on when the incident occurred, how many lanes were blocked, and how long the blockage lasted.

Congestion Impacts on Mobility, Public Safety, And Commerce

Major incidents that involve lengthy freeway closures have additional serious impacts on mobility and hence safety. Freeway closures affect intersecting arterial streets and other collector roads and even local streets. Cascading traffic congestion affects the ability to respond to medical emergencies, fires, and police calls that are not related to the freeway incident.

Freight shipment is also heavily affected at enormous cost to shippers and consignees. Many companies rely on "just-in-time" deliveries to provide goods and services. Even fairly short delays interrupt ontime delivery of supplies and materials and may shut down production lines.

What Is Traffic Incident Management?

To reduce the impacts of incidents on safety and congestion, traffic incident management is the process of coordinating the resources of a number of different partner agencies and private sector companies to detect, respond to, and clear traffic incidents as quickly as possible while protecting the safety of on-scene responders and the traveling public. Historically, public safety agencies applied the phrase incident management to the management process used for all types of emergencies from house fires to traffic crashes. After the construction of the interstate system, traffic incident management became critical to transportation agencies because incidents on freeways can trap motorists between interchanges and impede traffic flow and access by emergency vehicles. TIM requires an emergency response operational philosophy—24 hours a day, 7 days a week—which is a normal operating mode for public safety agencies but a new and different one for transportation agencies.

Many agencies and private sector companies are involved in TIM. Any single large incident may have dozens of agencies responding to specific needs. However, TIM is not a core function of any one agency, not even the owners of transportation facilities.

Eight major disciplines form the core constituency of traffic incident management: law enforcement, fire and rescue, emergency medical, transportation, towing and recovery, hazardous materials remediation, public safety communications and dispatch, and traffic reporting. (See "Who Are the Major Players in Traffic Incident Management?".) All have different roles on and off the scene, and their roles determine their operational priorities. Each also has a unique operational culture that often affects how well it interacts with other partners at an incident.

The ability to clear incidents quickly while providing safety to on scene responders and travelers is one measure of the success of a TIM program. The successful on-scene activities are supported by integrated interagency communications. Both the on-scene operations and the integrated communications structure are supported by a collaborative multiagency structure to resolve institutional policy and procedure issues and to provide the needed resources through a coordinated budgeting process.

Goals of an Effective TIM Program

Rapid response of appropriate resources to an incident and the quick clearance of that incident are, of course, the primary focus of a traffic incident management program. The main goals of effective TIM are to:

  • Protect both on-scene responders and the traveling public
  • Reduce delays and associated impacts on travelers
  • Reduce the possibility of secondary incidents
  • Ensure that response resources tied up at incidents are put back into service quickly

These goals may seem to conflict in that taking extra traffic lanes as a safety buffer for responders also may create additional disruption to traffic flow. Yet both goals can be realized if adequate warning is provided to motorists approaching the incident queue and positive traffic control is provided at all incident scenes on a 24-7 basis. In other words, if first responders can be assured that effective traffic control will be provided to increase their safety, they may be willing to close fewer lanes—taking only as many as they need for only as long as they need them.

Ingredients of a TIM Program—On-Scene Operations

At most traffic incidents an incident commander, most likely a law enforcement officer or a fire and rescue chief, coordinates the on-scene activities. For most incidents the command structure is simple and is largely implied through the duties of those who are on the scene. At larger incidents, especially those involving many agencies with overlapping jurisdictions, command and control may become complicated or even confrontational.

Top-of-the-line equipment such as the rotator pictured here enables towing and recovery companies to clear roads in minutes instead of hours.

The Incident Command System (ICS) provides the framework for command, control, and coordination of resources at the scene of the emergency. An objective-based system, ICS emphasizes common terminology, integrated communications systems, and comprehensive resource management. Also, under ICS, the command function (that is, the incident commander) can be performed collaboratively by representatives from agencies having jurisdiction at the incident under a unified command structure.

The lengthiest incidents typically involve spilled loads, hazardous materials, or fatal crashes. To clear these incidents quickly and safely, the responding partners must agree on procedures to investigate crashes and define crime scenes, as well as policies and procedures to aggressively remove heavy damaged vehicles and their cargoes, clean up spills of common engine fluids efficiently, and contain and clean up hazardous materials spills. All of this must be done while protecting on scene responders and incident victims in addition to keeping as many traffic lanes open as is safely possible.

Quick clearance techniques also apply to minor incidents such as stalled vehicles or minor crashes. Many States now have "Move It" or "Steer It, Clear It" laws that require drivers involved in noninjury crashes to move their vehicles immediately out of traveled lanes to safe locations. Most service patrols and many law enforcement agencies now equip their vehicles with push bumpers to move stalled vehicles to safe locations out of traffic and train their personnel on techniques for using the patrol vehicles' push bumpers.

Ingredients of a TIM Program—Communications And Technical Coordination

Responding efficiently and rapidly, managing resources at the incident, and providing areawide traffic control depend on the rapid exchange of accurate and unambiguous information between the responding parties. It is vital to provide a means of communicating voice, data, and video information on links that are field-to-field, field-to-center, and center- to-center, where "center" refers to traffic management centers, communications centers, emergency operations centers, and public safety dispatch centers.

The vast majority of incident communications within and between agencies is by voice through cellular telephone, radio, and other devices. However, interest is growing in integrating transportation and public safety data systems so that responders can exchange information more effectively.

Integrating the communications systems of disparate agencies, however, has significant institutional and technical challenges. The institutional questions include: With whom do agencies need to communicate? What information does each agency need? What information is needed from each agency? How does an agency communicate the necessary data while protecting sensitive data from unwanted or unlawful intrusions? The technical issues deal primarily with integrating new intelligent transportation system (ITS) data standards with public safety legacy standards in a way that will enable two-way data flow of accurate and unambiguous data.

Many urban areas now have traffic management centers and have deployed detection, surveillance, and control equipment, especially on freeways, to assist in the management of traffic. These systems can be extremely valuable in managing traffic affected by an incident. Traffic information is important to responders also, enabling them to reach an incident scene faster by a less congested route.

Using ITS systems for traffic incidents requires a concept of operations—or a roadmap of the interface between operational needs and technical capabilities. Operations concepts are typically developed for ITS systems but usually do not consider the needs of operational partners outside transportation, such as public safety agencies and the private sector. These operational concepts must be developed with the collaboration of other responders, particularly those in public safety.

Ingredients of a TIM Program—Program and Institutional Coordination

Most traffic incident management programs are not true programs at all, but are informally coordinated efforts led by key champions from one or more agencies, who agree to collaborate on managing traffic incidents. As long as those champions remain in their jobs, the management of incidents proceeds fairly smoothly. When a champion leaves, however, the successor may not have the same enthusiasm, sense of operational goals, or leadership strengths as the former champion. Without higher-level agency commitment to a more formal multiagency program, the "program" may suffer.

Coordinating the operations of many entities with conflicting priorities and functions can be extremely complicated and can be accomplished through some type of formal TIM program. Partner agencies in formal programs are bound by interagency agreements and guided by multiagency strategic program planning processes. They also have multiyear program plans or "roadmaps" to guide the budget planning processes of the partner agencies. Typically, the day-to-day program is coordinated by a multiagency and multidisciplinary team that meets on a regular basis to resolve issues of mutual concern.

A key piece of a formal TIM program is a multiagency strategic plan listing specific agreed-upon program goals and objectives. An important element to ensure the success of a strategic plan is to directly involve people responsible for implementing the plan during the development phase. Although high-level commitment is critical, action plans must make sense to field implementers or the plans will not be executed as intended. Involving both high-level and field-level stakeholders from the beginning ensures realistic plans with buy-in at all levels.

Many agencies measure performance by meeting goals. Measuring performance for a TIM program requires collecting data that may be different from agency-specific performance data. TIM program measures should reflect the program's objectives and not only those of individual agencies.

Current Status of Traffic Incident Management

In 2003, the Federal Highway Administration (FHWA) facilitated assessments of TIM programs in the largest 75 urban areas of the United States. The traffic incident management self assessment is summarized in two documents—Traffic Incident Management (TIM) Self Assessment: National Detail Summary Report and the Traffic Incident Management (TIM) Self Assessment: National Executive Summary Report. The national average score for participants in the assessments was 46.5 percent, out of a 100 percent maximum score.

Representatives from transportation and public safety agencies and private sector partners in each area conducted the assessments. Each assessment consisted of 34 questions covering three main TIM program areas: (1) operational issues, (2) communications and technology issues, and (3) program and institutional issues. Although the assessment is not inclusive of all regions, it does point to similarities and areas for growth for respondents, who participated in the assessment. FHWA also encourages other programs in other regions to use this tool as a benchmark for measuring present and future performance.

Service patrol technician assisting a motorist.

Current Status—On-Scene Operations

Of the program areas, the operational issues received the highest assessment with 57.3 percent (or 22.9 percent out of 40 percent). The operational portion of the assessment covered the policies, procedures, and processes used in the field while responding to an incident. Areas in this category included procedures for major incidents, responder and motorist safety, and response and clearance policies and procedures. Most TIM programs place emphasis on this area first, through the rapid and safe clearance of incidents.

The following States have used successful operational strategies as part of their TIM programs.

The Illinois Department of Transportation's (DOT) Minuteman program in the Chicago area is one of the oldest and most successful programs in the Nation. For more than 40 years, the program has focused on the aggressive removal of incidents from Chicago area freeways. On the average, major incidents blocking three or more lanes are cleared in 40 minutes. The average time for clearance of incidents blocking one lane is 12 minutes.

In Seattle, WA, early efforts were addressed at clearing truck-involved incidents through arrangements made with towing and recovery companies with special equipment. The average clearance time was reduced from nearly 6 hours to less than 90 minutes.

In San Antonio, TX, the TIM program resulted in a 30-percent reduction in secondary incidents. In Dallas County, TX, a TIM program goal to achieve an average clearance time for all incidents was set at 20 minutes, and the goal was met.

In Fairfax County, VA, aggressive monitoring of police resources deployed at arterial street crashes and efficient dispatch of towing and recovery services reduced the average clearance time of those incidents by 40 percent.

Current Status—Integrated Interagency Communications and Technologies

Part two of the assessment covered the communications and technology issues such as two-way voice, data, and video communications along with ITS initiatives for traffic incident management and traveler information. The national average score for this section was 41.7 percent (or 12 percent out of 30 percent), indicating that much still needs to be done to advance this component of traffic incident management.

The specialized vehicles shown here are used to facilitate quick incident clearance. Vehicles from Illinois, Tennessee, Washington, and Utah participated in keeping roads open during the Winter Olympics in Salt Lake City.

Although true data integration between public safety compute raided dispatch (CAD) systems and transportation management systems does not exist yet, strong efforts are underway in many locations. A U.S. Department of Transportation (USDOT) field operational test is taking place in Salt Lake City, UT, and in Seattle, WA, to integrate public safety and transportation data systems. In Austin, TX, the new Combined Transportation and Emergency Communications Center is a shared effort of a number of city and county public safety agencies, the local transit agency, and the Texas DOT. In the Washington, DC, area, many State and local public safety and transportation agencies and key Federal agencies are partners in the Capital Wireless Integrated Network (CapWIN), a project to integrate voice and data communications. A similar data integration effort also is underway in the Lower Hudson Valley, NY, just north of New York City.

Current Status—Regional and Statewide Programs and Institutional Coordination

The programmatic and institutional issues section of the assessment covered multiagency program development, support, and measurement. These scores were the lowest of the three sections of the assessments, at 36.7 percent (11 percent out of 30 percent).

Coordination is not project-oriented with a defined end point where success can be declared. Rather, these efforts are continuous and cross-jurisdictional across political lines, and they generally require agreements and strong relationships at high levels.

Maryland's Coordinated Highways Action Response Team (CHART) is a formal statewide program involving three State agencies at the strategic planning level and coordinating actions with county agencies. Statewide programs are also under development in Arizona, Florida, and Tennessee.

Washington State does not have a formal TIM program, but the Washington State DOT and the Washington State Patrol have enjoyed close working relationships for a number of years. In 2002, the two agencies entered into a Joint Operations Policy Statement (JOPS) that pledged cooperation on a number of issues of mutual interest, one of which was traffic incident management. One of the stated goals in the JOPS was to clear all traffic incidents in 90 minutes or less. This 90-minute clearance goal has become a national model that is now being adopted in other locations across the United States.

The Traffic Incident Management Enhancement (TIME) program in southeastern Wisconsin (Milwaukee area) is an example of a formal program at a regional level guided by a strategic planning process and involving regular meetings by a number of State, county, and municipal agencies. The TIME program has been successful for a number of years, especially with incident management at special events.

Although, these examples from various programs in all three areas of the assessment are a good start, FHWA is committed to working with State and local jurisdictions to "raise the score" through improving regional and statewide traffic incident management practices and promoting the integration of on-scene operations and communications among the many disparate agencies involved in TIM.

Who Are the Major Players in Traffic Incident Management?

Public safety agencies, such as law enforcement, fire and rescue, and emergency medical services (EMS) are generally called "first responders." Other agencies such as transportation (operations and maintenance), towing and recovery, and hazardous materials contractors generally are enlisted for specific services but act in support roles to the public safety responders, and are called "secondary responders." The terms "first responder" and "secondary responder" generally refer to the duties provided by the agencies and their relationship to immediate threats to life and property.

Law enforcement agencies provide 24-hour emergency response and operate under a paramilitary command structure. At most traffic incidents, law enforcement officers act alone and are trained to make unilateral command decisions.

Fire and rescue services provide 24-hour emergency response and operate on-scene under a well-defined command structure. Unlike police, who operate individually for most duties, fire departments function under a highly organized team structure with the close supervision of a commanding officer.

Emergency medical services have evolved as primary caregivers to individuals needing medical care in emergencies. As with police and fire, emergency medical personnel have a defined set of priorities. They focus on providing patient care, rescuing crash victims, and ensuring the safety of their personnel. In many communities, fire and rescue companies provide emergency medical services. In other areas, other public agencies or private companies provide those services to local jurisdictions under contract.

Under secondary responders, transportation agencies are typically called to the incident scene by first responders, usually law enforcement. Transportation personnel assist in traffic control, cleanup of debris, repair of damage to the highway infrastructure, and motorist aid. Transportation agencies also operate Transportation Management Centers (TMCs) that are the prime source of traffic information for the media.

Towing and recovery service providers are private sector partners responsible for the safe and efficient recovery and removal of wrecked or disabled vehicles, and debris from the incident scene. They operate under a towing contract or rotational call agreement usually maintained by a law enforcement agency.

Hazardous materials contractors are hired by emergency or transportation authorities to clean up and dispose of toxic or hazardous materials. Most common (and small quantity) engine fluid spills (such as oil, diesel fuel, gasoline, and antifreeze) can be contained and cleaned up without calling hazardous materials contractors.

Other agencies and private sector service providers play important roles in traffic incident management off-scene. Public safety communications personnel receive reports of incidents and provide the location and severity to the appropriate dispatch center, such as police, fire, or EMS. Using traffic feeds, detectors, and aerial surveillance, traffic reporting media collect incident data and provide reports to television, radio stations, pager systems, and the Internet.

FHWA Traffic Incident Management Program

At the national level, FHWA's Traffic Incident Management program provides national leadership and structure to regional and statewide TIM programs through technical assistance, guidance, training, identification of successful practices, and research on issues relevant to traffic incident management.

FHWA has sponsored TIM workshops since 1991. The current workshop is offered through the National Highway Institute (NHI Course Number 133048). The target audience is mid- and upper-level managers of both transportation and public safety agencies and representatives of private sector partners.

"The goal of the FHWA program should be to make it unacceptable to manage a major freeway or arterial system without having an established traffic incident management program that is coordinated with public safety and thinks beyond jurisdictional lines," says FHWA Associate Administrator for Operations Jeffrey F. Paniati. "Further, we should work to make reporting of system operations performance measures a standard practice at the State and local levels."

In 2004, FHWA facilitated publication of the Model Procedures Guide for Highway Incidents through a partnership with the National Fire Service Incident Management System Consortium. A panel of representatives from fire services, law enforcement agencies, and transportation agencies developed the guide. Paniati says, "It was an important achievement to get agreement on incident command procedures specifically for highway incidents. It is visible evidence of the growing partnership between the public safety and transportation communities."

FHWA is now developing an incident command training course and a companion publication, Simplified Guide to Incident Command Systems for Highway Incidents. The course and guide are expected to be available by mid-year of 2005.

In 2003, FHWA partnered with the Towing & Recovery Association of America, Inc. (TRAA) to develop the Traffic Incident Management Tow Operators Workplan, which was distributed to 37,000 TRAA member companies. The guide addresses traffic incident management issues for members of the towing and recovery industry from their perspectives.

This emergency service patrol vehicle carries an "arrow board," a portable directional sign used to direct traffic at the site of an incident.

In addition, FHWA and USDOT facilitated the development of a family of incident management standards for center-to-center data communication between public safety and transportation centers. A multidisciplinary panel of public safety and transportation representatives under the auspices of the Institute of Electrical and Electronics Engineers developed the family of standards (IEEE 1512). FHWA and USDOT are also sponsors of the CAD-Traffic Management Center Integration Field Operational Test now underway in Utah and Washington and the CAD-ITS Users Group, a USDOT-sponsored forum for persons involved in integrated public safety and transportation data systems.

National Traffic Incident Management Coalition

Facilitated through the American Association of State Highway and Transportation Officials (AASHTO), a new National Traffic Incident Management Coalition held its formative meeting on June 23, 2004, in Washington, DC. Comprised of representatives from transportation, public safety, and private sector organizations, the coalition's purpose is to provide a national forum for the public safety and transportation communities to coordinate experiences, knowledge, practices, and ideas for safer and more efficient traffic incident management. The goals are to:

  • Promote and support the successful development and conduct of regional and statewide traffic incident management programs through peer networking, mentoring, and knowledge exchange between public safety and transportation professionals
  • Develop and recommend multidisciplinary best practices, guides, standards, and performance measures in support of sound TIM activities
  • Develop and recommend appropriate research for referral to one or more of the coalition partners

The coalition provides a forum for disparate organizations and agencies that "own" a piece of traffic incident management to discuss and take action on issues of mutual interest. The work of the coalition will serve to bring national consistency to the widely varying sets of standards and practices used to address problems common to all.

Need for TIM

Traffic incident management is the true embodiment of "operations." It means being able to provide true "24-7" emergency response quickly and to coordinate that response among many disparate responding partners all having valid functions and different and sometimes conflicting priorities at the scene.

The events of September 11, 2001, drastically changed the perception of the transportation and public safety communities regarding the amount and nature of collaboration needed between incident responders. Now, public agencies and the private sector must interact more closely and cooperatively and share important information. Transportation and public safety partners have many opportunities every day to cooperate during "routine" traffic incidents. Experience gained from multiagency coordination of operations and communications for traffic incidents that occur daily provides the framework for efficient and coordinated response to large-scale emergencies and incidents. Gains made in traffic incident management operations and communications over the past dozen years have proven extremely important as agencies plan their responses to larger manmade or natural disasters.

Public safety agencies have always operated on a 24-7 emergency response basis in keeping with their functions, while transportation agencies traditionally have focused on building and maintaining roads, primarily in daytime hours. Recently, many States have started to shift construction and maintenance operations into nighttime hours. Even though transportation agencies often engage in "round-the-clock" activities related to major events such as snowstorms, floods, and earthquakes, providing full emergency response to traffic incidents is still rare. Operational demands in the 21st century will necessitate that transportation agencies look for ways to become full operating partners with public safety agencies.


David L. Helman is the FHWA program manager for Traffic Incident Management in the Office of Operations in Washington, DC. He has been with FHWA for 16 years and has spent the last 14 years in Traffic Incident Management. He has a B.A. from Rockford College, a B.S. from the University of Illinois, and an M.S. from West Virginia University. He is a registered professional engineer in West Virginia.

For more information, contact David Helman at 202-366-8042 or