Traffic Volume Maps by County

Traffic Volume Maps show the Annual Average Daily Traffic (AADT) numbers displayed at various locations on Maryland's roadways. Traffic counts are reported as the number of vehicles expected to pass a given location. This is an average day of the year for all traffic-counting stations in the state. Traffic volume data is collected from more than 8,700 Program Count Stations and 91 Automatic Traffic Recorders (ATRs) located throughout Maryland.

Program Count data is collected for both directions at regular locations on either a three–year or six–year cycle, depending on type of roadway. Growth factors are applied to counts that were not taken during the current year. The counts are factored based on the past yearly growth of an associated ATR. Counters are placed for 48 hours on a Monday or Tuesday and are picked up that Thursday or Friday, respectively. The ATR and toll count data is collected on a continuous basis. Toll station data is provided by the Maryland Transportation Authority.

Traffic Volume Maps are updated and published annually in March. Please see the Traffic Volume Map Introduction (PDF, 49KB) and ATR and Toll Locations (PDF, 48KB) for more information about the Traffic Volume Maps.

The entire 2017 Maryland Traffic Volume Map (11 MB) is available as a PDF file. To view, download, or print PDF files, you must have Adobe Reader installed on your computer. If you already have Adobe Reader installed, click the previous link.

To download a free copy of Adobe Reader, click here.

Note: PDF file sizes for the Traffic Volume Maps vary. It may take a few seconds or a few minutes to display. Please be patient while the file downloads.

To find a traffic volume map click on the county in the map below. A pop-up window identifying the traffic volume map you selected will open. Selecting the arrow pointing to the right opens a window with a hyperlink entitled Traffic Volume Map. Click this hyperlink to open the map in your browser to view, print or download.

The Traffic Volume Maps from previous years (1980-2015) are available by county as PDF files: Archive.