Traffic Monitoring

The Traffic Monitoring Group is responsible for the collection, analysis and reporting of vehicular traffic data on State Highway System routes. Traffic monitoring activities are mandated by federal law (23 CFR Part 500 Subpart B) and are essential functions of ADOT. The types of traffic data collected and reported include vehicle volumes, speeds, classifications and weights. This work is performed through the operation of a statewide network of permanent Automatic Traffic Recorders (ATR’s) and manual collections of  several hundred short-term data collection sites. The day-to-day field work of traffic data collection is a significant component of a traffic monitoring program.  Data collected must also run through a series of qualitative analytical checks and reviews before being released. Afterwards, the Traffic Monitoring Group distributes and publishes traffic data to satisfy the business needs of other ADOT groups such as Roadway Design, Materials and Motor Carrier Enforcement. Externally, traffic statistics are provided both monthly and annually to the Federal Highway Administration (FHWA) through its Traffic Management and Analysis System (TMAS) and Highway Performance Monitoring System (HPMS). The Traffic Monitoring Section will also collaborate with local government agencies in developing or enhancing their traffic counting programs, with the intent to ensure compliance with federal highway data reporting mandates.

To obtain timely traffic volume information related to COVID-19, please visit:

ADOT requires that all collected traffic data counts be shared through the ADOT Traffic Count Database System (TCDS) Module. Anyone looking to acquire the data should visit ADOT’s Traffic Data Management System (TDMS).

Average Annual Daily Traffic

Average Annual Daily Traffic- The total volume of vehicle traffic of a highway or road for a year divided by 365 days. This number represents traffic on a typical day of the year.


Data Dictionary
This dictionary defines the column headings and code values used in these files.