Traffic Diverter
Directional diverters block traffic from
proceeding onto a street in one direction.
Median diverters prevent traffic on the side
street from proceeding straight through the
intersection.
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Traffic diverters limit certain vehicle movements at an intersection to discourage cut-through traffic on neighborhood streets. Depending on the design, they may restrict left turns, through movements, or access from one direction while continuing to allow people walking and bicycling to pass through.
By reducing unnecessary vehicle traffic, diverters can create quieter, lower-speed neighborhood streets that are more comfortable for people walking, biking, and rolling. 1 2
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Note: The area highlighted in blue is intended only to illustrate the extents of the treatment and does not indicate or imply any colored surface treatment.
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Issues Addressed
Traffic diverters are most effective at addressing the following issues:
High volumes of vehicular traffic on neighborhood streets, especially cut-through traffic Broadside type crash patterns
Common Selection Criteria
A traffic diverter is considered where one or more of the following conditions exist:
Vehicle volumes are too high to maintain a comfortable and safe environment for people walking and biking on a neighborhood street.
Cut-through traffic has been identified as a recurring issue because drivers are using the neighborhood street as an alternative to nearby collector or arterial roadways. The desired outcome is to reduce vehicle volumes by changing travel patterns rather than by reducing vehicle speeds.
The surrounding street network can accommodate the redistribution of vehicle traffic.
Traffic diverters change where vehicles travel rather than how fast they travel. Because they redirect traffic to other streets, they should be evaluated as part of the surrounding transportation network rather than as an isolated intersection improvement. Traffic diverters are often most successful when there is broad community support and they are implemented as part of a neighborhood traffic management plan or bicycle boulevard, rather than as a standalone treatment.
Site Requirements
The following are general planning-level guidelines. Formal design requirements are provided in the City of Santa Monica’s Traffic Diverter Standard Plan. Median diverters require sufficient roadway width to accommodate the diverter while maintaining space for pedestrian crossings and emergency vehicle access. This may include repurposing an existing two-way left-turn lane or other excess pavement. Transit operations, emergency response routes, bicycle connectivity, and driveway access should be evaluated during project design.
Because traffic diverters redistribute vehicle traffic, additional traffic analysis and community outreach will be required to evaluate potential impacts on nearby streets and neighborhoods.
Complementary Treatments
High-visibility crosswalk
Crossbike markings
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DRAFT