Item B: West 11th Transportation Corridor Study

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CHAPTER 7: TRAFFIC SIGNAL TIMING EVALUATION th This section summarizes the assessment of the existing traffic signal timing along West 11 Avenue between Green Hill Road and City View Street. Based on the existing intersection geometry and existing traffic volumes, the project area was evaluated to determine if new traffic signal timing would provide improved traffic operations. Coordinated traffic signal timing along major roadway corridors is one of the most cost-effective 27 techniques for improving traffic operations and can produce benefit-to-cost ratios of 40:1 or more. Key benefits of updating traffic signal timing include fewer stops, reductions in traveler delays, improved safety, improved air quality (due to less fuel consumption and lower emissions), improved driver satisfaction, and more efficient use of existing transportation infrastructure. Evaluation The goal of the signal timing analysis was to determine if modifications to the existing signal timing would improve traffic operations and contribute to reduced travel times through the corridor. The analysis was accomplished by evaluating different cycle lengths, phase sequences, and subsystem configurations for each project area. A field review of the traffic operations during the AM and PM peaks was conducted to assess the existing conditions and gain an understanding of the corridor characteristics. Synchro was used as the analysis tool to evaluate the existing signal timings and to develop optimized signal timings for different scenarios. Performance measures from Synchro were used to compare the existing and proposed operations. The original limits of the analysis along West 11th Avenue were from Green Hill Road to Seneca Road. Due to the close spacing of the intersections and the desire to progress traffic along West 11th Avenue west of Garfield Street, the limits were extended to include the signals east of Seneca Road to City View Street. WEST 11TH AVENUE Existing Signal Timing th Currently, the traffic signals along West 11 Avenue between City View Street and the Fred Meyer driveway operate in a coordinated system from 7:00 am until 7:00 pm on weekdays. The signals along th West 11 (uncoordinated). th The traffic signal timings along West 11 Avenue were last adjusted approximately seven years ago. At -phase intersections (T- intersections) and 8- phase (protected or protected/permitted left turn phases on all four approaches) intersections. Some intersections have protected-only left-turn phasing and others have protected/permitted left-turn phasing. In both cases, the protected left-turn indications operate with leading left-turn phasing. There are heavy left turning movements at a few intersections and the variable distances between intersections makes it challenging to coordinate the signals with a common cycle length. 27 National Traffic Signal Report Card Executive Summary. National Transportation Operations Coalition, 2005. th West 11 Avenue Corridor Study September 4, 2009 City of Eugene P07265-003-000 51