In Florida, the Orlando-Orange County Expressway Authority found that driver uncertainty about congestion at E-PASS toll stations contributed to a 48 percent increase in crashes.
Date Posted
05/18/2001
Identifier
2001-B00179
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Safety Considerations in Designing Electronic Toll Plazas: Case Study

Summary Information

The Orlando-Orange County Expressway Authority (OOCEA) operates an 82 mile (132 kilometer) toll-road system with ten mainline toll plazas and 38 tollbooth ramps. The busiest mainline plaza is the Holland-East plaza, which has 14 toll lanes. Five lanes in each direction are stationary and four lanes are reversible. Of the ten toll plazas, the Holland-East plaza has the highest percentage of crashes (over 70 percent).

In May 1994, an electronic toll collection (ETC) system known as E-PASS was installed at the plaza. E-PASS uses automated vehicle identification (AVI) technology to recognize vehicles equipped with encoded data tags or transponders, and post a debit to the patron’s account without requiring the vehicle to stop. Prior to E-PASS deployment, speed variance was low and queues were long during peak hours, since all vehicles had to stop at the toll plaza. E-PASS was implemented in four stages. Stage 1 included manual and automatic lanes. In manual lanes, the toll is paid in cash to a human toll collector. In automatic lanes, the toll is paid to an automatic coin machine (ACM). In Stage 2, mixed AVI lanes (combining conventional and AVI lanes) were introduced. In these lanes, tolls are paid manually or with an AVI-equipped vehicle (or E-PASS vehicle). Stage 3 featured one dedicated AVI lane per direction with all other lanes being mixed AVI. In dedicated AVI lanes, payment is accepted only from E-PASS vehicles. There were two dedicated AVI lanes (or E-PASS lanes) in Stage 4. The arrangement of toll lane types provided many opportunities for vehicle conflicts (or crashes). Conflict points existed due to merging, queuing and speeding as drivers decided which lane to enter.

The study examined crash reports from January 1994 to June 1997 to identify crash frequency, causes, and types at the Holland-East plaza. In Stage 1, the average monthly crash rate per one million vehicles was 1.48 crashes per month. When E-PASS was introduced in Stage 2, the potential for rear-end collisions in E-PASS lanes increased due to driver confusion. The crash rate increased slightly to 1.68 crashes per month. After a dedicated E-PASS lane was added in Stage 3, queues were significantly reduced in the other lanes. However, merging increased due to unfamiliarity with the new lane type, which caused the crash rate jump by 53 percent to 2.57 crashes per month. After ten months of operation, a second E-PASS lane was implemented in Stage 4. Queue lengths in the non-dedicated lanes decreased, despite the loss of a manual lane. The rear-end crash rate increased slightly as manual drivers slowed or stopped in dedicated lanes before moving into adjacent lanes. The overall crash rate dropped slightly to 2.19 crashes/month. Crashes were more severe in Stages 3 and 4. E-PASS implementation increased the potential of all crash types, due to an increase in speed variance and driver uncertainty about lane configuration. The frequency of rear-end collisions and sideswipe collisions decreased as queue lengths were reduced and drivers became more familiar with the E-PASS system. The study also found that roughly 50 percent of total crashes occurred during the peak hours (7:00 to 9:00 AM and 4:00 to 6:00 PM), and that crashes involving pedestrians were more likely to occur with E-PASS.
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