As of 2024, there is only one published methodology to analyze frontage road operations. This chapter does not address freeway work zones, managed, or toll lanes. More information can be found in HCM 7th Edition, Chapter 10.

This chapter does not cover freeway to urban street interactions. For information on urban street interactions, refer to NCHRP 15-57 HCM Methodologies for Corridors Involving Freeways and Surface Streets (2020). It has information on evaluating operations and impact of spillback on networks that include both freeways and urban streets. This method evaluates freeway performance by lane, as spillback affects each lane of the freeway differently. The resulting trip-based performance measurement framework provides travel time estimates for given OD pairs within a highway network. Safety aspects of segment operations are also not covered in this chapter. See

Chapter 5

and

Chapter 6

of this manual for segment safety analysis information.