How does the City of Scottsdale determine speed limits?
The City of Scottsdale follows the guidelines set forth in the Manual on Uniform Traffic Control Devices (MUTCD) and the Arizona State Statutes to set speed limits in our city. The State Statutes allow local authorities to determine speed limits on streets under their jurisdiction based on an “engineering and traffic investigation.” The MUTCD provides the criteria that is used for the engineering study. The MUTCD states that the speed limit should be within 5 mph of the 85th percentile speed of free flowing traffic (the speed at which 85% of the vehicles are traveling at or less than). It also allows you to consider road characteristics, roadside development, parking and pedestrian activity, and crash experience. We do most of our studies based on citizen requests, in areas where the roadside environment is changing due to development, or where we have experienced a higher number of accidents than usual.
