About the Project
A typical traffic signal in the City of Omaha operates using one of three timing plans based on the time of day (AM peak period, PM peak period and off-peak periods). The timing plans are developed by traffic volume and direction of traffic on a given street and corridor during a given time of the day. The timing plans become out of date and lose effectiveness as traffic patterns change.
With many of the corridor timing plans in the City being out-of-date, the City of Omaha Public Works Department has started a program to update timing plans to accommodate current traffic patterns. The primary strategy for the corridor signal timings is to prioritize travel along the mainline corridor during peak periods and reduce average intersection delay during off peak periods.
Traffic signal timing efforts will take place concurrently with the Traffic Signal Infrastructure Upgrade projects to also take advantage of the enhanced capabilities from upgraded technology of the signal system such as operational benefits of flashing yellow arrows and improved traffic sensors.
Due to the number of corridors in the City, the effort to complete the re-timing efforts, and availability of funding, the retiming program will group various corridors together for a project to re-time the traffic signals. Each corridor re-timing project will take place in several phases as described below.
- Data Collection – Updated traffic counts will be obtained at each intersection in the corridor; existing signal timings/operations will be obtained and reviewed as well as the characteristics of each intersection in the corridor.
- Optimization –Software will be utilized to model the roadway network and traffic volumes, and optimized to develop a signal timing plan that minimizes overall delay and number of stops. In addition, vehicle and pedestrian yellow and red times will be updated to current standards, and additional analysis will be conducted for bicycle facilities, left turn operations, and order of phases.
- Implementation – Once new signal timings for a corridor are developed, the timing plans will be updated for the intersections in the corridor.
- Evaluation – Several measures to determine the effectiveness the timing plans will be recorded by driving the corridor, obtaining data from sensors, utilizing travel analytics software, and observing traffic with the timing plans in place. Recorded traffic signal timing data from the signal system central management software during the evaluation period will also be used to evaluate the operation of the timing plans.
- Refinement – Adjustments to the timing plans will be made based on the corridor travel results and traffic observations.