This report documents the findings of the evaluation of the North Seattle Advanced Traffic Management System (NSATMS) Project. The evaluation was originally designed to analyze the potential transportation benefits and costs of a regional arterial traffic data sharing system that would obtain traffic signal system information (volumes, signal timing plans, etc.) from participating agencies and then share the data among those agencies. The operational goal was to allow each agency to make better control decisions by providing it with real-time knowledge of traffic conditions outside of its own control system boundaries.
Because of a series of technical and project management issues, the system as originally envisioned was not successfully implemented. As a result, this evaluation does not include an analysis of direct operational benefits. It does, however, include a discussion of the expected institutional benefits, as well as an extensive "lessons learned" section based on the project team's review of the NSATMS effort. Of particular note were the importance of effective and ongoing lines of project communication, and the critical need to properly evaluate the fundamental nature of the project and provide a well-matched project management structure. The lessons learned from this project provide instructive guidelines for those who are contemplating future ITS system development efforts of comparable scope and complexity. Despite the limited successes of the NSATMS effort, the evaluation team found continued support for the regional arterial ATMS concept within the Puget Sound region. Follow-on research that contributes to a better understanding of the benefits, costs, and technical requirements of an arterial traffic management system is desired by many of the project participants.