Reliable capacity of electronic toll collection lanes

For proper planning, design and operation of an electronic highway toll facility, the capacity of the toll lane is an important aspect that needs to be considered. Though the capacity of roads and intersections are generarly referred to as stochastic in nature, toll lane capacity is still considered as a deterministic value. A study was undertaken into the variation in service headway and thus reliability related to capacity values for toll lanes. Videographic traffic data was collected at three electronic toll plazas in India. The service headway of cars found to be lower compared to vehicles with trailers. A Monte Carlo simulation was used for generating different variations that may occur in the service headway due to supply-side and demand-side changes. Finally, the capacity for 80%, 90% and 95% reliability was found as 494, 554 and 608 passenger cars per hour respectively. The developed capacity values can be used to check the volume-to-capacity ratio in a mixed traffic lane and can be used to develop the level-of-service thresholds for electronic toll collection lanes in future studies.