Speed Limits

The Town aims to set speed limits that are safe for vehicles, pedestrians and cyclists and that also provide optimum mobility. This requires a systematic review of several factors to determine the speed limit. Also, the Town is subject to Federal and State guidelines when it comes to determining speed limits.


The purpose of a speed limit is:

  • To provide a realistic limit, based on physical environment, that the vast majority of drivers voluntarily obey
  • To provide for more uniform flow of traffic
  • To define the speed at which most drivers can safely react to other vehicles, pedestrians or obstructions in the roadway

How the Town reviews speed limits

There are a variety of factors available to local jurisdictions to determine speed limits. These include 85th percentile speed - the speed that the majority of drivers deem to be safe - roadside development and access, accident experience, roadway geometrics, bicycle and pedestrian activity. An engineering study is also conducted as part of setting a posted speed.

Posted speeds must be reasonable. Speed limits are only meaningful if the majority of motorists comply voluntarily. Speed limits should also be predictable when traveling throughout different communities. Speed limits are also influenced by the design speed of the roadway.

State or local officials often receive requests for speed limit reductions because of perceived excessive speeds. However, research has repeatedly shown that changes in posted speeds have little effect on operating speeds.

Surprising facts about speed limits

  • Traffic studies show most people will drive the speed they perceive appropriate for a road's conditions and ignore a speed limit that is unrealistically high or low.
  • Speed-related accidents are more likely to be caused by speed differentials than by high or low speeds.
  • A reasonable majority of drivers voluntarily obey realistic speed limits, which helps with enforcement.
  • An unrealistic speed limit that is too low can make the behavior of the majority unlawful; cause antagonism toward law enforcement; create bad perceptions of a community; and result in significant speed differentials within the traffic flow.
  • Reducing the speed limit along a street will not automatically slow the speed of traffic, and increasing the speed limit will not automatically cause an increase in speed. Studies show it is generally at the upper boundary of a speed range where crash rates are the lowest.

Learn more about setting Colorado speed limits (PDF).