Sacramento-Watt Avenue transit priority and mobility enhancement demonstration project: phase III evaluation report

This report presents the results of the national evaluation of the Sacramento-Watt Avenue Transit Signal Priority Project, a cooperative project between Sacramento County and the Sacramento Regional Transit District (RT) to deploy transit signal priority (TSP) along a highly congested section of Watt Avenue just east of downtown Sacramento. The evaluation approach was to collect data to assess the impact of the transit signal priority on transit travel times and travel time reliability, and to determine if the addition of the system had an impact on traffic on either Watt Avenue or its cross-streets. Bus travel time data was manually collected on-board buses operating on the corridor before and after deployment of TSP, data from automated vehicle location devices on buses operating with and without TSP emitters was obtained, and travel time runs were conducted on Watt Avenue and its cross-streets before and after deployment of TSP. Data were compared to determine the impact of TSP. The results of the transit mobility and performance analysis showed that the average travel time for TSP equipped buses was between 14 and 71 seconds less than for non-TSP buses traveling over the same segments. For the control intersections (i.e., those without TSP), the travel times for TSP and non-TSP buses were similar, indicating that this difference can be attributed to the TSP. The results of the travel time reliability analysis showed that TSP did not significantly improve travel time reliability. For the segments of the corridor with TSP, TSP buses experienced better travel time reliability than non-TSP buses in two of the six time periods (as compared to one out of the six time periods) when looking at non-TSP intersections. The results of the traveler mobility analysis was inconclusive. Although difficult to state with much certainty, the results indicated that the addition of TSP on Watt Avenue had somewhat of a positive impact on Watt Avenue traffic and somewhat of a negative impact on cross-street traffic.