Traffic Census Program

Traffic Counts (a.k.a. Traffic Volumes) are for the State Highway System only (in various formats).

Highways are signed as Interstate, California State Route, or United States Route. See examples below:

     

Traffic count information for city and county streets may be found at the city Traffic Engineering or Public Works Department, or the Community Development Office in the area where the street is located.

• Explanation of Traffic Counts (Back & Ahead Leg Diagrams) (PDF)

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Caltrans Traffic Counts are summarized annually into four categories:

by Webpage:  2017

 

• Peak Hour Definitions K and D Factors (PDF)

For questions regarding AADT reports, Ramp Volumes, or the Peak Hour Volume Data Reports above, please contact Hasib Mohabbat.

For AADT GIS data, visit the Caltrans GIS Data webpage.