Volume & Turning Movement (VTM) Project

The focus of this project is to research how probe data can be used to estimate volumes throughout a highway network, which is then used for both operations and planning purposes. The Coalition has worked with member states to create the opportunity to compare probe GPS trace methodology to actual data. The results of this continued work will lead to the development of a volume estimate product that will give agencies the ability to move from estimating volumes from point data to using ubiquitous traffic volume data.

The VTM Steering Committee and members were updated on the results and status of the product development through web meetings.

For many agencies, network-wide volume data remains a key missing dimension for complete and actionable situational awareness, accurately assessing transportation system performance and developing targeted, cost-effective mobility projects and programs.

Tasks in process, include:

  • Testing implementation with agency partners
  • Confirming volume estimates can be used for AADT, ADT and real-time operations applications
  • Expanding calibration to arterials and low volume roads
  • Quantifying acceptable error bounds / thresholds for planning uses and for operations
  • Exploring if probe data can be used to test accuracy of non-ATR counters
  • Summarizing lessons learned and tips to address conflation needs.



Steering Committee

SC Meeting #9 (August 27, 2019)

SC Meeting #8 (August 16, 2018)

SC Meeting #7 (February 13, 2018)

SC Meeting #6 (November 9, 2017)

SC Meeting #5 (July 27, 2017)

SC Meeting #4 (April 13, 2017)

SC Meeting #3 (January 26, 2017)

SC Meeting #2 (October 13, 2016)

SC Meeting #1 (July 15, 2016)

Other Meetings

August 8, 2018 –  Meeting with New Hampshire DOT