Traffic signals are one of the most commonly recognized symbols of traffic control by the general public. Even the most uninformed traveler recognizes the impact that traffic signals have on travel. Travelers are also surprisingly astute in realizing when signals do not meet their needs for efficient travel. In fact, the FHWA 2000 Omnibus survey results showed that improving traffic operations is a significant issue for travelers. When asked what they recommended to improve operations, “improve traffic signal timing” was the second highest response and “checking traffic signals often” was the sixth highest.
Well-timed and maintained traffic signals and elements of traffic management such as work zone operations, managing special events and traffic incident response, monitoring of traffic and weather conditions and removal of localized traffic bottlenecks are routine operations strategies of public agencies. However, continuing growth in passenger and freight traffic indicates that a more proactive approach will be necessary to resolve congested conditions and the resulting unreliable service to motorists. Proactive management is only possible with a good analytical foundation and an objectives-based plan for how the traffic signal systems should be operated. This foundation should include the use of appropriate performance metrics, targets for performance, appropriate analysis tools to identify, develop and evaluate solutions to operational problems and an investment plan and capable workforce necessary to implement the chosen solutions. This proactive approach to traffic signal operations also requires the use of a systems approach to determine the most appropriate investment in existing or new technology to enable the implementation of solutions to operational problems.
There is little doubt that signal timing has a greater impact on transportation system efficiency than any other operational measure in the traffic engineering toolkit. Delays experienced in highway travel have been steadily increasing during the past 20 years. Delays at traffic signals contribute an estimated 25 percent to this total. Thus there is little doubt that focusing on traffic signal timing has potentially enormous payoffs for the quality of travel experienced by the U.S. public.
Traffic professionals have long recognized the value of designing effective signal timing and maintaining that timing to meet changing travel patterns and characteristics. Numerous authors have highlighted the fact that traffic signal timing is one of the most cost-effective actions that can be taken to improve surface transportation in urban areas.¹ Ten years ago, the U.S. General Accounting Office reported, “Properly designed, operated, and maintained traffic control signal systems yield significant benefits along the corridors and road networks on which they are installed. They mitigate congestion and reduce accidents, fuel consumption, air pollutants and travel times. These benefits are documented in numerous evaluations, provided to us (the GAO) by FHWA, states, cities and other sources, that compared before-and-after results when signal systems were installed expanded, or retimed. …For example, the state of Washington recently completed studies quantifying the benefits of upgrading and coordinating signal control equipment and retiming existing signals for six signal systems. These studies showed an annual fuel reduction of 295,500 gallons and annual reduction in vehicle delays of 145,000 vehicle hours.”² Various agencies have noted that a program of regular signal timing updates has a benefit/cost ratio between 20:1 and 55:1, with significant estimated annual user savings in the tens of millions of dollars.
Purpose of the Self Assessment?
The 2011 Traffic Signal Operations Self Assessment is designed to benefit participating agencies on several levels.
The objective of the self assessment is to provide a benchmarking tool for agencies to evaluate how their programs and practices support achievement of management and operations objectives and the expectations of system users and decision makers, more specifically by:
- Giving the traffic professional a guide for defining “good or best practice”;
- Highlighting improvement opportunities for your system or region;
- Serving as an objective tool to communicate traffic signal operation needs to management and policy makers;
- Presenting results in an easy-to-understand format that supports the need for additional resources and investment in traffic signal operations; and
- Providing a general comparison to results from the previous self assessment.
Your agency benefits by:
Identifying strengths and opportunities
The self assessment is designed to assist traffic professionals in assessing their own organization’s performance in creating and maintaining good traffic signal operation. The self assessment is a subjective and qualitative tool. The quantitative “score” should be viewed as an indicator of overall performance. Completion of the self assessment will help identify strengths in your system and opportunities for improvement, and the process of conducting the self assessment will be educational to agency staff.
Providing a benchmark for performance
The self assessment is designed to describe the benchmark for traffic signal operation practice. Each question is followed by a short description that illustrates outstanding practice. This provides your agency with a target to improve your own traffic signal operation. It is not anticipated that any agency will have a perfect score.
Increasing national awareness of the need for improved traffic signal operation
Completion of the self assessment supports the national initiative to raise awareness and bring attention to the need for improved management and operation of traffic signals. Some agencies experience strong funding support when elected leaders recognize the value of good traffic signal operation in reducing congestion. However, this level of recognition is not widespread. A high visibility press event to release the National Report Card will help to gain greater recognition of the role traffic signal operation can play.
Increasing local awareness of the need for improved traffic signal operation
Many agencies could benefit from additional attention to and investment in traffic signal operation. Completing the self assessment provides your agency with objective results to compare with national findings and to your previous results.
Registered participants who return their results by December 16, 2011, will receive the following:
- Certificate of completion;
- Personalized copy of your agency’s Traffic Signal Operations Self Assessment;
- 3rd National Traffic Signal Report Card Executive Summary and Technical Report;
- Press kit for conducting a local press event (including background information and graphics designed for the press, summary of national results, fill-in-the-blank templates for your agency's results, suggestions on conducting your local press event);
- A copy of the Traffic Signal Audit Guide;
- A copy of Improving Traffic Signal Management and Operations: A Basic Service Model; and
- Free access to traffic signal management and operations professional development courses.
National Report Card: How Are We Doing?
For years, transportation professionals have effectively identified pavement and bridge deficiencies and estimated the resources needed to maintain and improve those conditions. Traffic signals, a highly visible traffic operational tool, have not enjoyed the same level of attention.
NTOC, an informal coalition of associations interested in advancing transportation system management and operation, with support from the Federal Highway Administration (FHWA) developed a National Report Card on traffic signal operations. The National Report Card was to:
- Bring attention to the current state of signal operation;
- Create awareness of the congestion reducing benefits of good traffic signal operation; and
- Make a case for additional investment in traffic signal operation.
The 2005 National Traffic Signal Report Card was released through a media event, on April 20, 2005. The results contained in the 2005 National Report Card were based on responses to the 2005 Traffic Signal Operations Self Assessment. More than 300 state and local governments completed the self assessment and returned the results for compilation into the 2005 National Traffic Signal Report Card. The 2005 National Traffic Signal Report Card showed that traffic signal operation in the U.S. scored a "D-". A "D-" means that traffic signals are not operating as efficiently as they could be, resulting in unnecessary delay to travelers.
Subsequently, NTOC released the 2007 National Traffic Signal Report Card on October 9, 2007 based on the results of more than 400 state, county and municipal agencies that completed the 2006 Traffic Signal Operations Self Assessment. While the score improved marginally to a “D” it did show that a number of agencies experienced a marked improvement by taking a critical look at their traffic signal management program and making targeted investments in infrastructure, systems and/or agency processes.
¹ Wagner, FA. “Energy Impacts of Urban Transportation Improvements.” Washington, DC: ITE, August 1980.
² “Transportation Infrastructure–Benefits of Traffic Control Signal Systems are Not Being Fully Realized.” United States General Accounting Office Report to the Chairman, Committee on Energy and Commerce, House of Representatives. GAO/RCED-94-105, March 1994.