Signalized arterial represent a substantial component of the highway transportation network in the United States. The National Transportation Operations Coalition (NTOC) in their 2007 Traffic Signal Report Card noted that nationally 5 to 10 percent of all traffic delay is caused by improper traffic signal timings along major roadways. In 2007, the National Report Card for overall traffic signal systems operations was a D. The situation is not expected to improve as travel demand is forecast to grow significantly faster than network capacity. The increase in national attention on sustainable and livable communities necessitate a concentrated effort be placed upon improved management and operation of our nations traffic signal system inventory. The Transportation Management Center (TMC) Pooled fund study (SPR-2(207)) initiated in 2000, has been very successful at generating consensus on best management practices for traffic management centers oriented mainly towards freeway operations. It is desirable to develop a similar pooled fund study oriented toward traffic signal operations and management that would complement SPR-2(207) and engage a broad cross section of agencies on the leading edge of active traffic signal management.

Develop a network of transportation agencies to: i) develop consensus on operational standards of performance, ii) define a central management model that can leverage commercial wireless IP offerings that can be competitively outsourced, and iii) management principles for using a central system to identify when and where resources are most needed to maximize return on investment. The level of participation and associated funding commitments will allow for additional opportunities over time or in parallel to explore additional traffic signal initiatives beyond those described herein. For example, the evaluation of adaptive control field deployments and associated systems engineering guidance documents under development by FHWA.

The following are the three initial initiatives that the PFS intends to cover: (1) Development of Traffic Signal Standard of Performance and Related Measures Although centralized traffic management systems have been deployed for nearly 5 decades, there is limited consensus on standards of performance (operating objectives) or best practices for cost-effectively managing system operation based upon defined standards of performance. For example, most centralized systems can provide status reports on communication link quality, detector failures, and status of indications. However, none of the central systems have performance measure reports that provide systematic procedures for prioritizing signals or corridors with operating deficiencies that could be addressed by actively changing parameters such as green times or offsets. There are several innovative performance measure efforts emerging (based on the work of NCHRP 3-79a) that show promise for providing such a framework. However, their deployments have been limited to a few agencies and there is a need to develop broader national consensus to enable the private sector to understand what tools the industry needs and to guide their product development efforts. This task will recommend and validate uniform standards of performance and related measures for traffic signals and systems of traffic signals through evaluation of field trials in various operating environments. (2) Central System Architecture for Distributed Wide Area Systems Due to communication costs, centralizing the management of traffic signals has been focused on urbanized areas. Innovative private sector IP based communication plants offerings now make it practical to develop scalable integration architectures for managing signals distributed over large geographical regions, districts, and/or an entire state that can be competitively procured. However, central management systems targeted at high bandwidth, low latency fiber optic communication plants common in urban areas, must be developed to accommodate the nuances of geographically distributed communication plants with higher latency and lower bandwidth. For example, instead of polling every urban traffic signal once per second to obtain the status of signals and detectors, it is perhaps just as effective to poll each controller in an entire state once per day and download a compressed 300kb file with time stamped phase and detector events. Then, using the time stamped events, once per day, tabulate a series of user defined performance measures and rank the intersections and/or corridors for performance improvement opportunities. This task will develop a Central System Architecture that provides a scalable integrated management platform independent of variable communications latency and bandwidth. This platform shall integrate the automated evaluation of operating objectives as defined in task 1 above. (3) Management Concepts and Guidelines In a logical continuation of the performance based architecture developed above, the development of a new management framework is needed to allow agencies to identify when and where resources are most needed to maximize return on investment. For example, instead of re-timing all signals every two years, this approach would provide the supporting tools to identify signals in rapidly developing areas for re-timing perhaps as often as every six months, and in areas with now growth, the signal timings may not need to be updated any more frequently then every 5 years. This task will establish a proposed set of management concepts and guidelines that are "practice ready" and are based on the practical business case of maximizing the benefits of resources focused on traffic signal management.

Minimum commitment $25,000 per participant per year. One time contribution is also accepted