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Speed Limits

Speed Limit 3

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Who enforces speed limits?

Speed limits are enforced by law enforcement agencies such as the California Highway Patrol (CHP) or Sonoma County Sheriff's Office .

Request Enforcement

When motorists are consistently violating the posted speed limit in a given area, local residents often feel that lowering the speed limit will help slow people down. In fact this is usually not the correct solution. The best course of action is to contact CHP and request enhanced enforcement of the existing speed limit. When doing so, be sure to provide the days of the week and specific times of the day that you have observed the most violations.

Setting Speed Limits

Speed limits are set using the guidelines set forth by the Federal Highways Administration (FHWA), as well as on-site assessment by professional civil engineering staff.

FHWA - Engineering Speed Limits

FHWA - Methods and Practices for Setting Speed Limits: An Informational Report

If you believe that a speed limit should be changed, please contact us at (707) 565-2231. Please note, we cannot guarantee that your request will be granted. Engineering staff need to assess the situation to make a determination, and all new speed limits or changes to existing speed limits must be approved by the Sonoma County Board of Supervisors.

If you are seeking to lower a speed limit in your area due to frequent speeding violations, the more appropriate solution is to contact the California Highway Patrol to request enhanced enforcement.

Map of County Speed Limits

See full-screen map

Speed Limit 1 25 or Less Speed Limit 2 30 or 35 Speed Limits 3 40 or 45 Speed Limits 4 50 or 55