TRAFFIC SIGNALS

Institute of Transportation Engineers. ITE Journal,  Apr 2004  by Hofener, Steven D

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This month's issue of ITE Journal focuses on traffic signals. The public often views traffic signals as simple, inexpensive devices. I am amazed when I ask people how much they think traffic signals cost. Most people believe that traffic signals cost less than $10,000. They also believe that traffic signals should be able to give green time to everyone all of the time!

Other than interchanges, traffic signals are the highest form of traffic control available at an intersection. Today, traffic signal equipment is sophisticated and complex and requires continual attention. Many traffic signal variables have a long-term impact on the transportation system. Even the location and spacing of traffic signals is extremely important in the overall operation of the transportation system.

A transformation is taking place in transportation, and the Federal Highway Administration has taken the lead. The emphasis is a shift from just maintaining the transportation system to operating the system effectively by using all available resources. Maintenance is one single element in the overall operation of the system. As roadways become more congested and the ability to add capacity diminishes, the emphasis on operating the system increases.

Inherent in this shift is a renewed emphasis on operating the system on a regional basis. The public does not understand nor, in my opinion, does it care about city limit lines or jurisdictional responsibility. If the system is not operating effectively, the public wants it fixed! Cooperation and coordination are important to reducing multi-jurisdictional challenges.

Success in designing, installing and operating traffic signals crosses many disciplines and agencies. Traffic signal operation can and should be a major driver in the need for multi-jurisdictional (or regional) coordination. Multi-jurisdictions can include state departments of transportation, counties, multiple cities and councils of government, just to name a few.

However, the influence of traffic signals extends further. Traffic signals affect police, fire and emergency services, transit, goods movement, solid waste collection, pedestrians and bicycles, the hearing and sight impaired, the physically disadvantaged and so on. When designing a traffic signal, one must consider-in addition to all of the normal criteria-the need for wheelchair ramps, pedestrian and bicycle indications and buttons, audible indications, pre-emption for emergency services and priority for transit.

The ongoing operation and maintenance of traffic signals is one of the most important elements in the transportation system. It can have a lasting effect on the public. For example, vehicle detection systems that are not operating correctly can create unnecessary delays. Poor or outdated traffic signal timing also can create unnecessary delays.

The ability to operate and maintain traffic signals is influenced by political support (funding), the size and staff of the responsible agency, the amount of multi-jurisdictional coordination and staff training. While some elements are out of the control of the responsible individuals, many are not.

Although it can be challenging at times, I believe that we as transportation professionals have the responsibility and the ability to coordinate across disciplines and jurisdictions. Whether our expertise is in planning, transit, emergency services, traffic engineering, or another area, we can always strive to cooperate and coordinate.

Education and training are the two greatest assets to assist us with the operation of traffic signals within the transportation system. Both are within our control. Many resources are available through ITE, including numerous documents on the design, operation, installation and maintenance of traffic signals.

There is an ongoing effort, through the Professional Development Program Fund, to develop one-hour training modules on signal timing. The first two modules, "Traffic Signal Clearance Intervals" and "Engineering Intersections to Reduce RedEight Running," became available in March. The Online Learning Gateway program also has a module on traffic signals.

In addition, ITE is developing a four-module course for Easter Seals Project Action, which addresses the latest U.S. Access Board requirements for the design of traffic signals. A pilot of this course was offered on April 1, 2004 in conjunction with the ITE Technical Conference and Exhibit.

Traffic signal timing is a high priority for ITK and discussions are underway to develop additional training modules. ITE also will begin working with the AAA Trust Foundation to address pedestrian walking speed and how it can be integrated better into the signal design process.

I encourage you to read the articles in this issue. Use the ITE Web site as an excellent resource. Join a specialty council and become part of a listserv. Eet's educate ourselves, coordinate, cooperate and operate. Together, we can continue to make a difference!

STEVEN D. HOFENER, P.E., PTOE (F)