Effects of the Open Road Tolling on Safety Performance of Freeway Mainline

1 Advances of Intelligent Transportation Systems (ITS) technologies promoted the implementation 2 of open road tolling (ORT) on tolled freeways worldwide. This new tolling solution converts 3 existing barrier tollbooths to express lanes capable of collecting tolls at high-speeds. ORT has 4 demonstrated numerous benefits in reducing traffic congestion and air pollution. However, 5 effects of ORT on safety are still not clear, as most of ORT systems have only been operated for 6 a relatively short period of time. Therefore, this study aims to evaluate the safety impacts of ORT 7 by studying locations where such tolling solution was recently deployed on the Garden State 8 Parkway in New Jersey. Multiple-year crash data at the toll plazas before-after the 9 implementation of the ORT systems were used for analysis. Full Bayes methodology is 10 employed to estimate crash frequency models as a function of traffic and toll plaza 11 configurations. These models were used to estimate the crash frequency assuming that the ORT 12 systems were not installed. Then, these estimations were compared with the observed number of 13 crashes occurred after the deployment of the ORT systems. Individual comparisons show that 14 crash reductions are observed at most of the toll plazas. The overall comparison shows that 15 crashes at locations where ORT systems were deployed are decreased by about 24 percent after 16 deployment of these systems. It can thus be concluded that the use of ORT is a beneficial 17 solution towards improving toll road safety. From an implementation point of view, the analyses 18 results indicate that special attention should be paid to operational elements such as signage, 19 diversion and merge designs of the ORT systems. 20 TRB 2012 Annual Meeting Paper revised from original submittal. Downloaded from amonline.trb.org Yang, Ozbay and Bartin 3 INTRODUCTION 1 Open road tolling (ORT) is a new generation of tolling solution that will eventually lead to a 2 conversion of conventional toll plazas to barrier-free electronic toll collections in the future. By 3 design, ORT consisting of high-speed (express) electronic toll collection (ETC) lanes allows 4 vehicles to electronically and automatically pay tolls without slowing down from highway 5 speeds. Typically, there are two types of implementation of ORT (1). The first type is the all6 electronic ORT which completely replaces barrier tollbooths by express ETC lanes (2, 3). 7 Without the presence of tollbooths, this type of ORT design enables automatic debiting via in8 vehicle transponders (e.g., E-ZPass tags) or other automatic vehicle identification (AVI) 9 technologies. The second is the interim type of ORT implementation, which is being deployed by 10 many toll authorities. It installs express ETC lanes by retrofitting existing tollbooths to permit 11 high-speed non-stop toll collection for ETC users and other registered users only (1, 4). Cash or 12 coin users are still diverted to use remaining barrier booths off the express ETC lanes. 13 In the United States, many highway authorities in states like New Jersey, Florida and 14 Illinois have implemented the ORT concept in recent years (e.g., 5-7). Demonstration projects 15 have shown that the implementation of ORT is an effective means of relieving congestion. For 16 example, Klodzinski et al. (1) evaluated the addition of ORT to a mainline toll plaza in Florida 17 and found that installation of express ETC lanes reduced delays by 49.8 percent for cash users 18 and by 55.3 percent for automatic coin machine (ACM) users. According to Levinson and 19 Odlyzko (8), express ETC lanes of ORT can increase throughput, from 350 to 400 vehicles per 20 hour per lane with manual collection up to 2200 vehicles per hour per lane. The use of ORT has 21 also been shown to significantly reduce emissions. For instance, Lin and Yu (9) quantified 22 various ORT deployment scenarios on Illinois toll highways and suggested that the near roadside 23 carbon monoxide concentration levels and diesel particulate matter emissions can be reduced by 24 up to 37 percent and 58 percent, respectively. 25 While ORT can sharply reduce transaction-related delays and pollution at toll plazas, 26 safety impacts of retrofitting existing toll plazas and installing express ETC lanes, however, is 27 still not so clear. ORT systems can be deemed safer since high-speed tolls avoid the safety 28 deficiency of barrier toll plazas as they eliminate many stop-and-go traffic, dangerous 29 interactions and distractions (10). On the other hand, diverging and merging of vehicles that use 30 express ETC lanes at higher speeds might increase traffic conflicts (e.g., 11, 12). Cash and coin 31 users must exit to use the barrier tollbooths and then merge with high-speed users on express 32 lanes. These maneuvers may raise more safety issues. Unlike those easily measurable benefits 33 such as capacity improvement and reduction of costs in toll collection (e.g., 13-16), it is difficult 34 to evaluate safety performance of the new tolling solution shortly after its implementation 35 because of the random and rare occurrence of motor vehicle crashes. Quantifying safety 36 performance of ORT requires long-term crash data collected at toll plazas with and without the 37 deployment of ORT. 38 This study aims to evaluate the impact of implementing ORT on crash rates at toll plazas 39 by using extensive data collected at multiple mainline toll plazas with and without the 40 deployment of express ETC lanes on Garden State Parkway in New Jersey. The crash data 41 available in this study cover the period from January 2001 to December 2009. Therefore, safety 42 performance of toll plazas with and without express ETC lanes can be analyzed and compared 43 using these multiple-year crash data (17). 44 TRB 2012 Annual Meeting Paper revised from original submittal. Downloaded from amonline.trb.org Yang, Ozbay and Bartin 4 OPEN ROAD TOLLING IN NEW JERSEY 1 Gardens State Parkway (GSP) is a 172.4-mile limited-access toll parkway with 359 exits and 2 entrances. Over 380 million vehicles travel the GSP which stretches the length of New Jersey 3 (NJ) from the New York (NY) state line at Montvale to Cape May at the southern tip of the state. 4 Tolls are collected at 50 locations, including 11 mainline toll plazas and 39 on entrance and exit 5 ramps (18). It is among America’s busiest highways, serving users from NJ and NY’s most 6 marketable communities (19, 20). 7 The GSP operator (GSP was operated by the NJ Highway Authority (NJHA) until 2003 8 and later by the NJ Turnpike Authority (NJTA)) always focused on using new toll collection 9 technologies to improve tolling efficiency and reduce congestion. After the first toll collected 10 manually in 1954, automatic coin machines (ACM) were introduced in early 1950s and had 11 spread to most toll plazas and ramps on the Parkway by 1959 (21). When a toll increased beyond 12 the quarter, tokens were introduced in the early 1980s. They continued to be available until 13 January 2002 and ceased to be accepted in payment in January 2009 (21). Regular (low-speed) 14 ETC system was implemented in 1999. The entire ETC system was completed in August 2000 15 (20). The ETC system has been widely adopted by travelers with an ETC penetration rate beyond 16 70 percent on GSP (22). 17 In 2001, the state government issued an order to promote a 10-year congestion relief plan 18 for GSP (13). Under the plan, elimination of mainline barriers in one direction and use of express 19 ETC lanes of ORT in the other were recommended. By 2010, all mainline barriers except Toms 20 River were converted to one-way tolling (express ETC lanes were added to both directions at the 21 Toms River toll plaza). Between 2004 and 2006, the open road tolling program was implemented. 22 Express ETC lanes of ORT have been installed at a number of toll plazas listed in TABLE 1. 23 TABLE 1 Open Road Tolling Operation at the Mainline Toll Plazas on GSP 24 Toll Plaza Milepost ORT Operation Date No. of Express ETC Lanes Cape May NB 19.4 May 2006 2 Toms River NB 84.7 May 2005 2 Toms River SB 84.7 May 2005 2 Asbury Park NB 104.0 May 2005 3 Raritan SB 125.4 May 2005 5 Pascack Valley NB 166.1 January 2004 2 Pascack Valley SB 166.1 January 2004 2 25 Installation of express ETC lanes at the Pascack Valley toll plaza in January 2004 marks 26 a major milestone of ORT deployment on GSP. FIGURE 1 shows the progression of toll 27 collection at the toll plaza. The conventional toll plaza with seven tollbooths in one direction was 28 retrofitted to an interim version of ORT system, which allows ETC drivers to drive at 55mph 29 through the two high-speed lanes in each direction. Followed this demonstration project, this 30 type of ORT system has been successfully deployed at several other sites listed in TABLE 1. 31 FIGURE 2 shows an example of the layout of the converted plaza. Signs are installed upstream 32 of the toll plaza to guide the selection of tollbooths. Upon the operation of such ORT system, 33 electronic readers mounted on the gantry automatically charge the ETC vehicles. Meanwhile, 34 overhead cameras capture the license plates of vehicles without transponders (e.g., E-ZPass tag). 35 Cash and coin users are diverted to use barrier tollbooths. The new ORT system has been widely 36 accepted as over 90 percent E-ZPass vehicles use the high-speed lanes on GSP. It is estimated 37 that express ETC lane can process about 800 more vehicles per hour than traditional ETC lanes 38 (10). Compared to the observed benefits such as capacity improvement and reduction of costs in 39 TRB 2012 Annual Meeting Paper revised from original submittal. Downloaded from amonline.trb.org Yang, Ozbay and Bartin 5 toll collection (e.g., 10, 13 & 14), little information about the safety impact of the deployed ORT 1 system is available. 2 3