In its mission to maintain Pennsylvania's transportation system, PennDOT monitors traffic information, provides traffic and Geographic Information Systems resources for partners and stakeholders, and much more. The department also facilitates safe
traffic counting across the state.
National Highway System (NHS)
Frequently Asked Questions
What are traffic counts used for?
Traffic information is critical in transportation decision making related to highway funding, traffic engineering, highway design, planning, programming, and air quality analysis.
When is traffic count data collected?
PennDOT has an established program for collecting traffic data. Traffic data is collected at approximately 30,000 sites statewide. The sites are on various collection cycles: annually, every three or five years, depending on priority of the highway system. 10,000 traffic counts are taken each year at selected locations.