Traffic Section

The Traffic Section collects traffic data, addresses traffic related questions and complaints, and administers traffic calming, guardrail, traffic signal, and sign and marking efforts on county roads.

Traffic Counts

The Department of Highways and Transportation maintains a listing of 24-hour “average daily traffic” counts (ADT’s) for most of the county, maintained collector, and arterial streets. Most local streets (i.e., subdivision streets) are excluded, for they typically have low, yet fairly static daily and annual numbers.

Inquire About Trends & Road Counts

Department of Public Works does not post or publish this information primarily for the reason that the count program is ongoing at all times and is routinely updated. Interpretation of count data and terms can be confusing to a lay person. For this reason, Department of Public Works invites interested parties to contact us directly to inquire about specific roads and trends.

The Maryland State Highway Administration annually re-counts many locations on state highways and roads. They produce an annual map of these counts. Be advised that you will need Adobe Acrobat Reader to view the file.

Count Machines

One should not be immediately alarmed that a road upgrade may be pending if you see a count machine (as evidenced usually by a rubber tube across the road connected to a toaster-sized box) on your street. Often, this is merely a regularly scheduled event to update our database of information.

Intersection Turning Movement Counts

Neither the County nor the State performs regular “intersection turning movement counts.” These counts involve counting each movement, i.e., right turn, left turn, or through movement, that occurs at an intersection. Usually these counts are recorded over 2 or 3-hour windows of time, such that the “peak hour” within that window can be derived. Typically, a private consulting firm performs this style of count. This type of information is also used in determining “traffic signal warrant” thresholds and “level of service” analysis.

Traffic Signalization

To view the warrants necessary to justify a traffic signal, please review Chapter 4 of the Manual on Uniform Traffic Control Devices.

All major subdivisions and commercial projects must undergo studies to determine if roadway improvements (and other concerns) need to be mitigated.  All large projects and all projects in already-congested areas will be screened to see if traffic signals are necessary.

Request for new traffic control signs and signals

Contact Us

  1. Engineering Supervisor

    David Olney
    Ph: 301-600-2930

    Frederick County DPW Main Office:

    355 Montevue Lane, Suite 200
    Frederick, MD  21702-8213

    Ph: 301-600-1129
    Fx: 301-600-3517


    7.30 a.m. - 4 p.m.

    After Hours Emergencies

    Please call Emergency Communications
    Ph: 301-600-1603

State Roads Contact: