Traffic count study and signal timing for a congested junction

The junction of Main Street and Fifth Avenue in Ridgeway County carries about 3,400 vehicles in the evening peak hour. It has run the same fixed-time signal plan since 2011: a 120-second cycle with two phases. Since a 300-bed hospital opened on Fifth Avenue last year, queues on the northbound approach reach 400 m, ambulances get stuck, and pedestrians from the bus stop cross against the signal because the walk phase is too short.

The county traffic engineer wants a new timing plan before the winter, when traffic peaks. She has given you two days of video from the junction, which you will simulate in this project with a synthetic turning movement count based on the volumes below, and asks for a timing plan that can be programmed into the controller.

Evening peak estimates by approach: - northbound Fifth Avenue: 980 vehicles per hour, with 30% turning left into Main Street; - southbound Fifth Avenue: 720 vehicles per hour; - eastbound Main Street: 920 vehicles per hour; - westbound Main Street: 780 vehicles per hour; - heavy vehicles around 6%, with buses on Main Street every 8 minutes; - about 260 pedestrians per hour crossing Fifth Avenue at the bus stop side.

You will produce: - a count data set in 15-minute intervals and the peak hour factor; - adjusted volumes, saturation flows and critical lane groups; - a phasing plan, considering a protected left turn for northbound; - a cycle length and green splits using Webster's method, with yellow and all-red intervals and pedestrian minimum times; - a capacity and delay check with level of service by approach; - a short memo and a timing sheet the signal technician can enter.

Done means a timing plan with a cycle under 120 seconds if possible, no approach over 0.9 volume-to-capacity, and a pedestrian walk time that meets the minimum.