Annual Surveillance of Urban Traffic Growth

This paper describes a methodology for the preparation of operations plans for the annual surveillance of traffic growth during the continuing phase of the urban transportation planning process. The use of the traffic-counting program for the determination of vehicle-miles of travel by functional system and area is described, with detailed examples from the Columbia and Greenville, S.C., urban areas. Three principles of count-program planning are offered: there must first be an identification of those roadway links for which the laneage requirements are particularly sensitive to forecasted volumes, or at which traffic growth may be so unexpectedly rapid as to indicate an earlier stage of programming; second, count histories should be prepared for each facility, by link; finally, a reevaluation should be undertaken at 5-yr intervals to determine whether certain count stations should be changed in location or discontinued as hourly or seasonal counts.