If a city or county thinks the speed for a particular street or highway should be changed it can make a request to ODOT for a review and investigation. Requests are submitted to the Traffic-Roadway Section via email to [email protected] which initiates an investigation to determine if a speed zone should be changed. The region traffic engineering staff conducts an investigation using procedures in accordance with nationally accepted traffic engineering standards. Factors taken into consideration are crash history, roadside culture, traffic volumes, and roadway alignment, width and surface.
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A major factor in establishing speed zones is consideration of the 85th percentile speed. This is the speed at or below which 85 percent of the vehicles are traveling. This is used as an indication of the speed most drivers feel is reasonable and safe.
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When the investigation is complete, a report with photographs detailing the existing conditions and proposed changes is prepared. The report is sent to the city or county for review. If the city or county agrees with the recommendation, the new speed zone is established.
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If ODOT and the local road authority cannot reach agreement on the setting of a speed zone, the speed zone request is referred to the Speed Zone Review Panel. The panel is comprised of representatives of the Oregon Transportation Safety Committee, the Oregon State Police, the Association of Oregon Counties, the League of Oregon Cities, and ODOT. The panel hears ODOT’s recommendations and testimony from the local road authority and makes the final decision. It is the responsibility of the road authority to install new speed zone signs.