Book Description

The purpose of this report is to look at the state-of-the-art of non-traditional traffic counting methods. This is done through a three-fold approach that includes an assessment of currently available technology, a survey of State Department of Transportation practices, and a review of the literature. Traditional traffic counting has utilized intrusive devices including bending plate, pneumatic road tube, inductive loops, and piezo-electric sensors. As safety, cost, increased traffic flow, complex road geometrics, and traffic disruption have become issues of concern, traffic counting professionals are looking more closely at alternatives to traditional methods of data collection. Such non-traditional traffic counting devices as video image detection, Doppler microwave, passive magnetic, passive acoustic, active and passive infrared, and active and passive ultrasonic are being considered due to their non-intrusive nature. Information on available technology including cost, installation requirements, technical specifications, data retrieval, and limitations of the products are addressed. This information is followed by a summary of State practices that shows very limited usage of non-intrusive technology. Lastly, a review of the literature indicates there is little in the way of "new" technology. However, several evaluations of non-intrusive devices provide valuable information to traffic counting professionals that will assist in decision-making regarding upgrades to current practices