GIS Traffic Count Data

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Traffic by Roadway Segment (Segment Layer)

This layer represents historic traffic data along their corresponding  route segments.

Traffic by Count Locations (Point Layer)

This layer represents historic traffic data at the location that the traffic count was done.

Traffic Data

Traffic data is displayed in reports of historical Annual Average Daily Traffic (AADT) and Annual Average Daily Weekday Traffic (AAWDT).

Viewable attributes are:

  • K factor
  • D factor
  • Direction splits
  • Percentage
  • Single-unit trucks
  • Combination trucks

The data is in Nad83 (HARN)/Maryland (ft).

Full data sets and filtered data sets can be viewed in spreadsheet, Shapefile and KML file formats. 

Data is available as either a point layer, which represents the location where the count was done, or segment layer, which represent the roadway section corresponding to the count. 

Traffic data is updated and published annually.

Data items are defined and described in Data Description (PDF, 221 kb)