Where did IDOT get the traffic data used in the computer model?
There are two types of traffic data that can be used in traffic noise modeling: • Peak Hourly Traffic • Average Daily Traffic (ADT) – The total traffic volume during a given period divided by the number of days in that period. Current ADT volumes can be determined by either continuous or periodic traffic counts. Existing volumes are typically generated from actual traffic counts. Future volumes are typically projected by the highway department or a metropolitan planning organization, based on typical traffic growth rates, planned development and projected growth for the area.
