Safety Assessment of Barrier Toll Plazas

The future of the barrier toll plazas on the toll roads such as the Garden State Parkway is currently a subject of discussion in New Jersey. Taxpayers, expecting an efficient and safe transportation system, have expressed concerns that barrier toll plazas are creating more costs than just a 35-cent toll. Groups who support keeping the toll plazas such as NJTolls.com are challenged by groups such as Citizens Against Tolls, resulting in a politically sensitive situation. Recent improvements including the introduction of Electronic Toll Collection (ETC) completed in 2001 have been followed by discussions of Open Road Tolling (ORT) or removing the toll plazas completely. The issue is whether the revenue generated by the tolls is worth the social costs associated with them – namely delay, accidents, and pollution. This study focuses on the cost of accidents associated with the barrier toll plazas on a specific toll road namely, the Garden State Parkway. A review of previous studies determined the need for investigation as well as providing a means of comparing results. Sections of the Garden State Parkway were then selected and labeled as toll areas and non-toll area. Non-toll areas of similar traffic volume and travel conditions to toll areas provide an appropriate means of comparison. Accident data from 1998, 2001, and 2002 was obtained to provide a comparison for the effects of ETC on the accident rate. The data was then analyzed to answer the above questions in terms of changes in accident rates both between toll and non-toll locations and before and after the implementation ETC. Finally, a regression model was developed to determine what variables influence the accident rate at toll plazas on the Garden State Parkway. The goals of this study are to provide information on the differences in accident rates at toll plazas compared to non-toll sections of the Garden State Parkway and to determine if ETC has reduced delay at the expense of safety. The difference in accident rates represent how many more accidents are occurring at tolls than would be occurring if the toll plazas were removed and the toll section was just another typical section of the Parkway. A cost of accidents are then estimated based on these findings. Keywords – accident analysis, toll plazas, costs