Evaluating the Quality of Signal Operations Using Signal Performance Measures

The Utah Department of Transportation (UDOT) has taken an active role in evaluating and monitoring traffic signal performance throughout the state. The Automated Traffic Signal Performance Measures (ATSPM) show real-time and history of performance at signalized intersections. UDOT uses the various measures to evaluate the quality of progression of traffic along corridors, while displaying unused green time that may be available from various movements. The information gained through the ATSPM data helps to inform UDOT of vehicle and pedestrian detector malfunctions, while also measuring vehicle delay and recording volume, speed, and travel time of vehicles. UDOT uses the measures to optimize mobility and manage traffic signal timing and maintenance to reduce congestion, save fuel costs, and improve safety. The use of the ATSPM data has been helpful in optimizing signal operations across the state. The system generates a large quantify of data; however, the data are currently not being utilized to their full extent. One need that has not been met with the ATSPM data is to provide context for performance measure data and to provide a history of this context over time. Although a large quantity of data has been generated for the signal performance measures data, users still must generally rely on their own experience and expertise to provide context to the quality of operations across the state. There is a need to evaluate the performance measures data over time to provide situational awareness of the performance of the system. This will allow the UDOT Traffic Operations Center (TOC) staff to identify trends in performance, to identify which areas may have a decreasing level of service (LOS), and to identify intersections or corridors with the most urgent needs. The purpose of this project is to evaluate the data collected through the ATSPM database and determine which performance measures can be used for this evaluation and to then identify thresholds for each performance measure chosen. The research would dig into the data to determine what is happening across the state to answer questions such as: (1) Which signals are performing poorly (based on the criteria identified)? (2) How is the overall performance of signals, corridors, and/or regions changing over time? and (3) Which signals are experiencing operational vs. maintenance problems?

  • Supplemental Notes:
    • Contract to a Performing Organization has not yet been awarded.


  • Status: Active
  • Sponsor Organizations:

    Utah Department of Transportation

    4501 South 2700 West
    Project Development
    Salt Lake City, UT  United States  84114-8380
  • Start Date: 20190124
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01703046
  • Record Type: Research project
  • Source Agency: Utah Department of Transportation
  • Files: RiP, STATEDOT
  • Created Date: Apr 26 2019 12:13AM