January 19, 2022


This month, Caltrans employees are receiving a customized training on the fundamentals of the Highway Capacity Manual (HCM) and McTrans’ Highway Capacity Software (HCS). This is the newest iteration of a training that Kittelson staff have been offering for more than 30 years.

History of Kittelson’s Highway Capacity Manual Training

Kittelson staff have provided HCM training to federal, state and local transportation agencies, universities, and professional organizations since the publication of the 1985 HCM (the last one to rely on manual calculation worksheets and the beginning of software). The training has made its way across the United States, as well as to South Korea, Ghana, South Africa, and Australia. The teachers are rotating groups of Kittelson staff, who apply their experience to bring up real world situations as they present HCM concepts.

The January class is being led by Aaron Elias, who has previously given the training in both Oregon and Washington, and Mychal Loomis, who joined Kittelson in 2021 in San Diego.

“I’m excited to able to use my experience as a practitioner on the teaching side of things,” says Mychal. “It’s a good opportunity to better myself along with those who attend the training.”

What the Training Will Cover

Past versions of this training have ranged from 1-2 day courses that cover specific facility types (such as roundabouts, signalized intersections and freeways), to the full range of facilities covered in the HCM. The training for Caltrans will provide a primer of HCM methodologies over a multi-day 26-hour online class, covering both interrupted flow (such as signals and roundabouts) and uninterrupted flow (such as freeways and two-lane highways). The training includes discussions on application of the HCM and specifically, the use of Highway Capacity Software put out regularly by McTrans. Our engineers enjoy teaching using software tools such as HCS since these software tools are the primary way engineers implement the methodologies of the HCM.

What’s New in the Highway Capacity Manual

While the focus of the training is HCM basics, whenever we offer this class, we spend time discussing what has changed since the last version of the Highway Capacity Manual. In this case, we’ll have a new edition to work from, since TRB released the 7th edition in January 2022. The HCM 7th Edition incorporates 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.

Future Highway Capacity Manual Trainings

The training is simple and cost-effective to replicate and offer virtually to other agencies. If you’d like to learn more, start the conversation by reaching out to Aaron or Mychal directly.