Roadway Information and
Traffic Monitoring System Program
Truck Weight Data
WIM, as defined by the American Society for Testing and Materials (ASTM), is “the process of measuring the dynamic
tire forces of a moving vehicle and estimating the corresponding tire loads of the static vehicle”.
Interest in the number of heavy vehicles operating on roadways in North America grew in parallel with road construction
growth. It has been apparent that heavy vehicles are a major component to road damage and important in bridge design. It
is also apparent that there are limitations associated with static scales and their ability to enforce weight limits and
to collect unbiased data.
In addition to weight data, WIM sites collect a variety of traffic data. Data includes traffic volume, speed,
directional distribution, lane distribution, date and time of passage, axle spacing, and vehicle classification.
The PDF files below are in Portable Document Format (PDF). You will need Adobe Acrobat Reader to view the PDF file,
which is available free from our
state Adobe access page.
Permanent Weigh-in-Motion (WIM) System Sites
2012 WIM Site Locations List
2012 WIM Site Locations Map
Truck Weight Monitoring
Equivalent Single Axle Load (ESAL) Design Factors 2012 (pdf 282k)
Vehicle Travel Information System (VTRIS)
2011 Weekday Average Speed