You are here:
Follow this link to review the Frequently Asked Questions concerning Speed Zoning.
American law follows the basic idea that most people are reasonable and laws exist to control the few who are unreasonable or inconsiderate. The posted speed zones follow the same idea. The methods for establishing speed zones are based upon careful studies that have been performed in Oregon and throughout the United States.
Posted speeds override these statutory standards.
All travel on public streets and highways is subject to the Basic Speed Rule. The Basic Speed Rule states that a motorist must drive at a speed that is reasonable and prudent at all times by considering other traffic, road and weather conditions, dangers at intersections and any other conditions that affect safety and speed. In other words, drivers are expected to use good judgment in selecting their speed. The Basic Speed Rule does not authorize a driver to exceed the posted speed. If a motorist is charged with violation of the basic speed rule, the posted speed becomes the primary evidence that he/she exceeded the Basic Speed Rule. In this case, it would be up to the motorist to prove that he/she was driving in a reasonable and prudent manner for the conditions. A person can also drive below the posted speed and violate the Basic Speed Rule. For instance, if there is ice or snow on the roadway, a driver can be traveling less than the speed posted and still be traveling faster than is reasonable and prudent for the conditions.
In addition to the Basic Speed Rule, some roadways in Oregon have specific speed limits. Speed signs posted on interstate freeways, any roadway within a city, and school speed zones reflect speed limits. In addition, speed limits apply to certain types of vehicles -- large trucks, school buses and vehicles transporting children or workers. Speed limits do not authorize speeds higher than those required for compliance with the Basic Speed Rule. Conversely, the Basic Speed Rule does not authorize speeds higher than those established as speed limits.
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 ODOTSpeedZoning@odot.state.or.us 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.
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.
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.
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.
Work Zone Speed Reduction Request, Form 734-2874
Contact The Traffic Engineering Services for assistance: 503-986-3573.
With the exception of temporary construction or emergency speed zones orders, all speed zones on interstate highways in Oregon (I-5, I-82, I-84, I-105, I-205 & I-405) are set by statute (ORS 811.111) at 65 or 70 mph for passenger cars, unless otherwise directed by OAR 734-020-0011.
A recommendation for setting speed limits on interstate highways in Oregon can be found in:
Interstate Truck Speeds
In 2017 ODOT performed an engineering study on the impacts associated with increasing truck speeds on interstate highways. Information about this effort can be found on the Interstate Truck Speeds page.
Online Copies of Speed Zone Orders NOTE: You may be prompted to install Whale Communications software that will enable you to properly access the Order Form data. If this occurs, click "Install" and follow any instructions. We apologize for the inconvenience.
Current designated speed zone orders statewide
When you get to the search page there’s a few things to know in order to help you find your document:
Training classes in conducting speed zone investigations are offered periodically to local agency personnel.
Your browser is out-of-date! It has known security flaws and may not display all features of this and other websites. Learn how