Chapter 6 - Cross Section Elements

6.9. Frontage Roads and Access Roads

AASHTO defines a frontage road as “a road that segregates local traffic from higher speed through-traffic and intercepts driveways of residences, commercial establishments, and other individual properties along the highway” (Green Book, 2004).

Frontage roads provide numerous functions depending on the type of arterial they serve and the character of the surrounding area. Frontage roads may be used to control access to the arterial, to provide access to adjoining property, and to maintain traffic circulation on each side of the arterial. Frontage roads segregate local traffic from the higher-speed through traffic and intercept driveways from residences and commercial establishments along the highway. Most existing frontage roads were built along interstate or major arterial routes to provide control-of-access to the highway and access to property that would otherwise be land-locked. Frontage roads typically run parallel to the mainline roadway while access roads provide access to individual properties and may not run parallel to the mainline.

Access roads may also be used to provide access to landlocked parcels. Access roads and frontage roads should be offset from the highway to allow required clear zone and future roadway widening, if anticipated.