Under the direction and partial funding of the United States Department of Transportation, national evaluations of Intelligent Transportation Systems (ITS) projects are being conducted to accelerate the integration and interoperability of ITS in metropolitan and rural areas and to investigate the success of ITS across the country. One of those evaluations is of a transit signal priority (TSP) system that was deployed along Watt Avenue in Sacramento, California. The objective of the evaluation was to determine the extent to which TSP improved (a) transit system mobility and performance by reducing intersection delay and (b) schedule reliability by reducing travel time variability. Baseline, or 'before' data was collected during a two-week period in March of 2003, and 'after' data was collected during a one-week period in March of 2004. While collecting the 'after' data, the evaluators encountered several challenges that both impeded the evaluation and reduced the effectiveness of the TSP system. This paper describes this evaluation, identifies the challenges that were encountered, and summarizes the results of this evaluation to date. The paper also describes plans for overcoming the challenges that were encountered in order to complete the evaluation.
Samenvatting