Using performance based planning to fight congestion

Schwartz, William L 3/6/98

One of the significant changes in transportation planning practice that has resulted from ISTEA is the increasing use of performance measures. Performance-based planning reflects a growing demand among key decision makers and professionals for greater accountability in the investment of public transportation funds. This concern is echoed in other governmental sectors as well as in private industry, and is directly related to an increased emphasis on the quality of service provided to users or "customers" of the transportation system Based on these trends, it is likely that performance-based planning will become an increasingly important component of the transportation planning process. (See lead article for a discussion of how California is working towards development of a performancebased process.)

Recent work in congestion management has led to some "lessons learned" in the challenging task of performance-based planning. For example, typical performance measures used for congestion management systems have included travel time, delay, and travel speed. While these performance measures provide valuable information and can be generated with existing data and tools, more service-oriented measures are needed. Performance-based planning focuses both on measuring the quality of transportation services as perceived by system operators and users and on the broader impacts that transportation systems can have on society. For example, performance-based planning measures need to be clearly related to and derived from broad societal goals, such as quality of life, economic vitality, etc. Current research indicates that many performance measures currently in use are often not good surrogates for the intent of transportation programs. Specifically, managing congestion may be the solution needed to accomplish a goal such as improved quality of life or sustainable economic activity. But in practice, managing congestion has become the goal itself, with little or no attention given to the goals that are more difficult to measure.

One of the fundamental concepts in performance-based planning is a growing awareness of the effectiveness as well as the efficiency of transportation services. Effectiveness is best defined in relation to what transportation delivers to the customer. Example goals include providing mobility for all citizens in the community, or providing access to economic activities. One way to apply this concept to congestion management is to incorporate and measure mobility and access.

Another important element of performance-based planning is the measurement of external impacts, such as the effects of transportation system operation and construction on the environment and society. Examples of these externalities relevant to transportation include air quality, noise levels, dislocation of households and businesses, wetlands impacts, and water quality. There are also secondary or indirect impacts associated with the increased development that can occur as a result of enhanced accessibility.

These concepts are the topic of research being conducted as part of National Cooperative Highway Research Program (NCHRP) Project 8-32(2), Multimodal Transportation: Development of a Performance-Based Planning Process. The findings of this research effort will be documented in a Performance-Based Planning Manual, and presented in workshops.

Contact:

Steve Pickrell, Cambridge Systematics, Inc, 510/973-8700.