• Contact Information

    Transportation and Engineering


    Monday - Friday
    7:30 a.m. - 5:30 p.m.

    Contact Us

    100 Jefferson County Pkwy.
    Ste. 3500
    Admin and Courts Facility
    Golden, CO 80419

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  • Speed Limits 

    A popular misconception is that reducing the speed limit will automatically slow the speed of traffic, while raising the limit will automatically cause traffic speeds to increase. “Before” and “After” studies have shown there are no significant changes in vehicle speeds after limits are changed.

    This is because people tend to drive the roadway at a speed that is comfortable, given the conditions, and will ignore a speed limit that is too high or too low. Traffic flowing at a uniform speed increases safety and results in fewer accidents. Drivers are less impatient, pass less often and tailgate less, reducing both head-on and rear-end collisions.

    A realistic speed is voluntarily obeyed by the reasonable majority, and more enforcement effort can be applied to the unreasonable few who drive too fast or too slow.

    Speed Limit Sign

    Establishing Speed Limits: 

    In Colorado, for roads that are not posted, speed limits are:

    • 20 mph on narrow, winding mountain roads
    • 25 mph in any business district
    • 30 mph in any residential district
    • 40 mph on open mountain highways



    Speed limits should not be set higher or lower than these limits unless a traffic study has been performed to justify the change. This applies to all state highways, county roads and city streets. The study includes an analysis of roadway conditions and accident records and a count of the prevailing speed of traffic. A safe and reasonable limit is then established at or below the speed at which 85 percent of drivers travel.

    The Colorado Department of Transportation brochure on "Establishing Realistic Speed Limits Download Adobe Reader from Downloads Page" provides additional information.

    Speed Limit Violations

    Neighborhood speeding problems should be reported to the Jefferson Sheriff's Office Traffic Unit at 303-271-KOPS (5677).

    Last Updated: 7-26-2016