This document defines and provides examples of different types of road classifications including: - Functional classifications such as freeways/expressways, major arterials, minor arterials, collectors, and local roads based on the type of traffic and speeds they carry. - Jurisdictional classifications including interstate highways, state highways, and county roads based on ownership and maintenance responsibilities. - Other road types like public roads, private roads, city streets, alleys, and connectors designed to provide access to properties and connect to higher order roads while discouraging through traffic.

1. ENGINEERING
ENGLISH
Transportation and highways vocabulary
Roads

2. Functional Classification
• Categorizing roads based on the type of
service provided:
• freeway/expressway,
• major arterial,
• minor arterial,
• collector,
• connector or local road.
• Examples?

3. Freeway/Expressway
• A highway that serves inter-regional and intra-
regional trips, and carries heavy volumes of
traffic at high speeds. Examples: I-205; the
Milwaukie Expressway (Oregon Highway 224)

4. Major Arterial
• A road that primarily carries local and
through traffic to and from destinations
outside local communities; connects cities
and rural centers, and carries moderate-toheavy volumes of traffic at moderate-tohigh speeds.

5. Minor Arterial
• A road that primarily connects collectors to
higher order roadways, and carries moderate
volumes of traffic at moderate speeds.

6. Collector
• A road that is a principal carrier within
neighborhoods or single land use areas. Collectors
link neighborhoods with major activity centers, other
neighborhoods and arterials and are generally not
for through traffic. They carry low-to-moderate
volumes of traffic at low-to-moderate speeds. New
collectors should intersect minor arterials rather
than major arterials.

7. Public Roads
• Roads owned by the County or on a County
easement that are not maintained by the
County; maintenance responsibility lies with
abutting property owners.

8. Private Roads
• Roads owned by a private property
owner. Public access and use is by
permission of the property owner.

9. City Streets
• Similar to County roads, except under
the jurisdiction of a city.

10. Local
• A road designed to provide access to
abutting property and to connect to higher
order roads. New local roads should
intersect connectors, collectors or, if
necessary, minor arterials. Traffic calming
measures may be appropriate. Local
roads are inappropriate for through traffic.

11. Alley
• An alley provides access to the rear of
properties and may be public or private.
Alleys should intersect local roads or
connectors. Alleys are not for through
traffic.

12. Jurisdictional Classifications
• A classification of roads based on
ownership of the road.

13. Interstate Highways
• Multi-lane federal highway that provides
connections to major cities, regions of the
state and other states. Interstate highways
are major freight routes. Maintenance
responsibilities belong to the Oregon
Department of Transportation.

14. State Highways
• State-owned roads that provide the primary
connections to larger urban areas, ports and
major recreational areas that are not directly
served by interstate highways. Maintenance
responsibilities belong to the Oregon
Department of Transportation.

15. County Roads
• Public roads for which the Clackamas
County Board of Commissioners has
accepted maintenance responsibility.