Regional Signal Timing Plans
The Bipartisan Infrastructure Bill (BIL) established the Carbon Reduction Program (CRP), a new regionally competitive grant program managed by RTC. The CRP authorizes grant funding for projects designed to reduce transportation emissions. RTC was awarded funds to develop signal timing to improve traffic flow, safety, and air quality in the Clark county urban area. RTC in coordination with local agencies in Clark County, Washington and our consultant will develop regional signal timing plans along major corridors in Clark County.
Decreased Vehicle Emissions - The reduction in idling time for vehicles reduces the amount of emissions that enter the atmosphere. Vehicles emissions include the following products: nitrogen oxides, volatile organic compounds, carbon dioxide, particulate matter, and sulfur dioxide. Reduction of these emissions improves the environment and air quality for all citizens.
Shortened Travel Time – Retiming signals can reduce the amount of time and number of times drivers are stopped at a red light through a corridor. The reduction in stops allows drivers to travel through the corridor in less time.
Reduced Fuel Consumption - A reduction in fuel consumption is realized as the amount of time vehicles spend idling is reduced. The reduction in fuel consumption saves drivers money by decreasing fuel usage.
Increased Safety - Improved signal operations not only leads to benefits in congestion, fuel economy, and air quality as described above, but it can also reduce crashes. According to the Federal Highway Administration, providing improved signal coordination on a corridor can reduce crashes by 15%.
Increased Travel Time Reliability – The reduction in congestion and decrease in crashes will contribute to a more reliable driving experience meaning driving along the corridor will, in general, be more similar from day-to-day. Travel time reliability is not only important to commuters but commercial/ freight traffic as well.
Major tasks include prioritize corridors; review/update traffic signal timings; deploy signal timings, and produce reports. The process includes collecting data for the corridor, conducting model development/analysis, drafting timing plans, developing final timing plans, implementing the signal timing plans through participating local agencies, and reviewing and adjusting the signal timing plans.
To prioritize the corridors, a screening criteria/process was developed, which includes evaluation criteria such as mobility, safety, delay, transit utilization, and travel time reliability.
Corridors being evaluated and prioritized include congestion management corridors.
The following corridor performance measures and criteria weighting factors were quantified and evaluated for each of the corridors considered in this process:
The VAST Steering Committee prioritized the CMP corridors using the performance metrics and weighting factors mentioned above. The results from their prioritization can be found on the table below.
Once corridors have been prioritized, corridor signal plans will be developed and implemented in priority order. It is anticipated that signals timing plans will be developed for about 2/3 of the corridors prioritized. Plans will be developed in order of priority. However, signal timing plans for corridors with current or upcoming construction will be moved to the next year to ensure that the data captured depicts the most accurate existing conditions.
Results will be reported to regional stakeholders and the public to keep them informed about the project’s progress.
Regional Signal Timing Plans Schedule
