The EUPRP&DC has two types of traffic counters that it uses to collect data:
1. The Gamma counter is a self-contained, microprocessor-based data collection recorder that works with road tubes to record the axles of detected vehicles. It is designed for simplicity in field operation with corresponding computer software to aid in the translation of the axle data into vehicle information. The recorder collects time tagged data that can be analyzed to provide speed, axle classification, gap, and vehicle information. The Agency has 4 of these types of counters.
2.The Nu-Metrics HI-STAR Portable Traffic Analyzer features patented Vehicle Magnetic Imaging technology that can record volume, speed and length classification of vehicles plus road surface temperature, wet/dry surface condition and roadway occupancy. These 2 counters are used mostly on city streets, as they are laid in the middle of the lane and taped down.
Counts are typically 7 day’s in length, although some are as short as 48 hours. The raw data is the total of both lanes averaged out. The Annual Average Daily Traffic (AADT) is the raw data multiplied by seasonal factors developed by MDOT and then averaged.
MDOT maintains traffic count information for all State Trunklines and M-roads throughout the State. MDOT has recently started collecting traffic count information on local County roads/City streets as well. You can search all MDOT’s count data by visiting this website http://mdotnetpublic.state.mi.us/tmispublic/Search.aspx. Enter a start and ending year, select the County from the dropdown menu, and optionally select “County Roads” from the Route Designation dropdown menu (or leave blank for all MDOT counts).
Traffic Count Map
EUPRPDC has started an inventory of traffic counts and their locations in its RoadSoft database. Currently only 2005 and 2011 counts are entered. More years will be updated in the months to come.
MDOT’s segment counts are also included, and are shown on the map in red. These segments will be updated annually.