To finish up on the Signal Optimization Blog Series, I would like to close with a Case Study about URS Corporation and their experience with a signal optimization project in Western Ottawa County, Michigan.
As you’ll read below, the Western Ottawa Signal Optimization Study by URS is a great example of the effect that optimized signals can have on our drive times, pedestrian safety, and our environment.
URS Corporation has completed numerous signal optimization studies, corridor studies, and other traffic operational and safety studies in Michigan. Their projects often involve reducing fuel consumption and emissions by improving travel times throughout transportation networks.
In 2010, URS Corporation was retained to conduct a signal optimization study in Western Ottawa County, Michigan. The study included extensive data collection for 129 intersections, including eight hour turning movement counts at each intersection.
Of the 129 turning movement counts, 122 of them needed to be collected during an eight-week span in April and May only on Tuesdays, Wednesdays and Thursdays before school let out for summer. An aggressive project data schedule!
To help collect data within the constraints of the project, URS Corporation rented 11 of Miovision’s video collection units to collect data at 80 of the 122 intersections. Using a video collection unit to collect data is not as time intensive as sending a manual counter, since a video collection unit can be set up in less than ten minutes by a trained technician, then left to record data.
Signal Optimization Objectives
The goals for the Western Ottawa Signal Optimization project included:
- Reduction of fuel consumption and emissions
- Improvement (reduction) of vehicle travel times
- Standardization of traffic signal operation parameters, including pedestrian crossing clearance time updates
- Improvement of transportation safety for the motoring public, pedestrians and bicyclists
- Mobility improvement without additional capital investment in road and bridge improvements
Signal Optimization Results
The signal optimization project in Western Ottawa County provided many benefits to its motorists and the environment, including:
- Overall benefit-cost ratio was 12.5:1, with an annual savings to the motoring public of $5 million.
- Fuel consumption reduction (saving over 273,000 gallons annually).
- Air pollution reduction (over 1,000 tons annually).
- Travel time improvements (saving over 311,000 vehicle-hours of delay annually).
- 13 of 15 corridors experienced travel time reductions.
- Traffic signal hardware improvements (including GPS clocks to aid in maintaining coordination).
- Anticipated vehicle crash reduction of 10% based on historical results from a similar signal study.
In addition to the benefits to motorists, the signal optimization study saw improvements that benefited non-motorized transportation as well. The implemented benefits include:
- installation of pedestrian pushbuttons
- longer pedestrian crossing clearance times
- consistent operational characteristics of pedestrian countdown timers
- shorter traffic signal cycle lengths
A full analysis of URS’ Signal Optimization Study has been recorded into a webinar available on Miovision’s website. To watch the webinar, click URS Corporation Signal Optimization Webinar
The benefit-cost ratio of 12.5:1 in Western Ottawa clearly shows that Signal Optimizations Studies are worth the money. Motorists traveling through the network will enjoy shorter travel times, and as a result, output less pollution. The study also provided pedestrians with safer, more accessible conditions when interacting with the roadway at a controlled intersection.
This wraps things up for the Signal Optimization Blog Series. I hope that you’ve enjoyed reading the installments along the way.
In May, we’ll be launching Roundabout Month to correspond with the TRB 3rd International Conference on Roundabouts. A quick YouTube search on Roundabouts makes me excited for some fun blog posts, including one about The Magic Roundabout in the UK.