Shoulder (road)

A shoulder (American English), hard shoulder (British English) or breakdown lane (Australian English) is an emergency stopping lane by the verge on the outer side of a road or motorway. Many wider freeways, or expressways elsewhere have shoulders on both sides of each directional carriageway—in the median, as well as at the outer edges of the road, for additional safety. Shoulders are not intended for use by through traffic, although there are exceptions.

Purpose

Shoulders have multiple uses, including:

Emergency vehicles such as ambulances, fire trucks and police cars may use the shoulder to bypass traffic congestion in some countries.

In the event of an emergency or breakdown, a motorist can pull into the shoulder to get out of the flow of traffic and obtain a greater degree of safety.

Active traffic management, used on busy multi-lane roads, may allow 'hard shoulder running' by general traffic at reduced speeds during periods of high traffic volumes.

In some places a "bus bypass shoulder" may be provided which allows bus services to pass stationary traffic.

Paved shoulders provide additional space should a motorist need to take evasive action (such as avoiding a wrong-way driver) or need to recover control of their vehicle before a run-off-road collision occurs.

In some rural areas without sidewalks, pedestrians and cyclists may be allowed to walk or ride on the shoulders.

On curbed roadways, shoulders move the gutter away from the travel lanes which reduces the risk of aquaplaning, and reduces splash and spray of stormwater onto pedestrians using any adjacent sidewalk.