The Truck Volume Maps depict; the average percentages of trucks at various locations on Maryland’s roadways. Classification data is collected from a percentage of more than 8,700 Program Count stations and 91 Automatic Traffic Recorders (ATRs) throughout the State of Maryland. Program Count data is collected (both directions) at regular locations on either a three (3) year or six (6) year cycle depending on type of roadway. Growth factors are applied to counts which were not taken during the current year and 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.
The Truck Volume Maps have the data represented as percentages of the total traffic volume for the classification counts taken during the years 2012 - 2014. The truck data is split into two categories according to Federal Highway Administration (FHWA) guidelines: Single Units (classes 4-7) and Combination Units (classes 8-13). In case of multiple counts at the same locations and ATR data, the percentages are averaged over the entire data set for that station. The maps show two set of percentages, one next to the other. The first is the percentages of Single Units and the second is the percentage of Combination Units. The two classes are described in the Description of Classes document (PDF, 235 kb). The current Annual Average Daily Traffic (AADT) is shown above the percentages.
Please see the Truck Volume Map Introduction (PDF, 153 kb) for more information about the Truck Volume Maps.
The entire 2014 Maryland Truck Volume Map (9.81 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.
Please Note: The PDF file size for the Truck Volume Maps vary as such, the Truck Volume Map that you select may take a few seconds or a few minutes to display fully, please be patient while the file downloads.
View the Truck Volume Maps by County Archive for Year 2007 - 2013
The Truck Volume Maps from previous years are available only as PDF files: Archive