November 30, 2021


The Transportation Research Board (TRB) has made the decision to officially release the 7th Edition of the Highway Capacity Manual in time for the TRB 2022 Annual Meeting, as opposed to the previously discussed HCM 6.1.

Why a 7th Edition?

The decision to release HCM 7.0 instead of 6.1 was driven by several factors:

  • Digital Format: The HCM 7th Edition will be the first edition of the HCM that will be available not only in printed format, but also in electronic e-book format that is hyperlinked and searchable.
  • New and Expanded Procedures: Content-wise, HCM 7.0 will incorporate significant additions or expansions to computational procedures resulting in updates to more than one third of HCM 6.0.
  • Errata: The HCM 7th Edition will address all errata and revisions from HCM 6.0.

What’s New in HCM 7.0

The HCM 7th Edition will formally incorporate significant additions or expansions to computational procedures, including:

  • Guidance on application of HCM methods to determine capacity impacts of connected and automated vehicles (CAVs).
  • A new network analysis method to evaluate spillback between freeways and urban streets, estimate travel time across facilities, and conduct lane-by-lane analysis for freeways.
  • A new two-lane highways analysis method that offers improved analysis of two-lane highway capacity and operational performance.
  • Enhancements to existing pedestrian analysis methods at signalized intersections and uncontrolled crossings.

HCM Sessions at TRB 2022

If you’ll be at TRB 2022, you can learn all about HCM 7.0 at Lectern Session 1245, “Highway Capacity Manual Upgrade: What Is New for the 7th Edition?” Kittelson’s Bastian Schroeder and Paul Ryus will be speaking at this session. We have been honored to contribute to this update and work on several of the computational procedures described above, and we look forward to being a part of this and several other TRB sessions dedicated to the next edition of the essential guide to moving people and goods.