Field Evaluation of Alternative Real-Time Methods for Estimating Approach Delay at Signalized Intersections

Vehicle delay at a signalized intersection is among the widely used performance measures of efficiency at a signalized intersection. The Highway Capacity Manual (HCM) uses this performance measure to report the level of service at a signalized intersection. This performance measure is also used to estimate travel time along the arterials. With the advent of technological advances in the field of vehicle detection, real-time measurement of delay at a signalized intersection has become economically and computationally feasible. This paper compares three emerging techniques for estimating approach delay: an Input Output technique (IO), a Hybrid technique, and the HCM delay equation. The techniques were tested under varying traffic conditions at the instrumented intersection in Noblesville, IN.