Safe Waves: Signal Timing Guide, Analysis Tool, and Case Studies

Speeding on arterial roads can be reduced by timing traffic signals to minimize the number of speeding opportunities – occasions when a vehicle arrives at an intersection on a stale green with no vehicle ahead for at least five seconds. The “Safe Waves” approach to traffic signal timing aims to minimize speeding opportunities while still providing good two-way progression using short cycles, short coordination zones, pedestrian recall where pedestrian demand is moderate and undersized phases where it’s low, and offsets that prevent high-speed progression. A test on a suburban arterial found that with Safe Waves signal timing, the number of vehicles exceeding the speed limit fell by 75%, while arterial travel time increased by only 2 seconds per intersection. A simulation-based case study in another suburban corridor found that Safe Waves signal timing reduced speeding opportunities by more than 50%, while network delay per vehicle rose 2 s in the p.m. peak and 21 s in the a.m. peak. A web app, the Safe Waves Analysis Tool (SWAT), was developed to enable designers to visualize and count the speeding opportunities afforded by a proposed arterial signal timing plan.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Maps; Photos; References; Tables;
  • Pagination: 155p

Subject/Index Terms

Filing Info

  • Accession Number: 01919599
  • Record Type: Publication
  • Created Date: May 28 2024 9:14AM