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You're going the wrong way: The surprising benefits of changing direction



About a mile down the freeway, Debra Acey, driving a 1997 sports utility vehicle (SUV), entered westbound I-90 going the wrong way. Seconds later, Fischer's car slammed head-on into Acey's SUV. The impact hurled both vehicles off the interstate in opposite directions, killing Klotz instantly and seriously injuring Fischer.


As in most wrong-way crashes, investigators couldn't determine exactly how and why Acey drove right past two large "Wrong Way, Do Not Enter" signs and entered the freeway going the wrong way. But one circumstance was certain: Acey's blood-alcohol level was 0.30, more than three times the legal limit of 0.08. Prosecutors charged Acey, 44, with vehicular homicide and vehicular assault, the Seattle Times reported.




You’re going the wrong way.




Driving the wrong way on freeways has been a nagging traffic safety problem since the interstate highway system was founded in the late 1950s. Despite four decades of highway striping and sign improvements at freeway interchanges, the problem persists.


Studies, such as those performed by the Washington State Department of Transportation (WSDOT), show the vast majority of wrong-way drivers correct their mistakes before causing a crash by simply turning around and heading in the right direction. But for unknown reasons some drivers, even when sober, head straight into oncoming traffic with devastating consequences.


"While there are safety programs exclusively for rail crossings and work zones," says Eckhart, "I am not aware of any national-level program to combat the wrong-way problem. However, at the State level, some States such as California do have a wrong-way prevention program that funds safety improvements." State departments of transportation (DOT) across the country have taken additional measures to improve ramp designs, signage, and striping to prevent wrong-way incidents. Other States are experimenting with intelligent transportation system (ITS) technology to address the problem.


Upon receiving a contact closure, the Lanex device enters a time stamp into its system log with the label "wrong way" and saves that portion of the hard drive from being rewritten. At the same time, the recording device increases recording speed from one frame every 2 seconds to two frames every second. This increased speed helps improve image quality for the next recorded minute. By having the device record before the incident, researchers can see the direction the vehicle is coming from and observe the driver's behavior. With this information traffic engineers hope to learn more about how and why drivers wind up heading into oncoming traffic.


A WSDOT study of wrong-way incidents over a 10-year period along a 129-kilometer (80-mile) section of I-82 from Yakima, WA, to the Tri-Cities area (Richland, Kennewick, and Pasco) showed that there were 30 wrong-way crashes from 1986 through 1996 along this corridor, 11 of which involved a total of 15 fatalities and three serious injuries.


From May-December 2001 the Lanex system recorded 18 wrong-way incidents. Of those, 12 drivers, or 67 percent, turned around and returned, while 5 continued on and disappeared from camera view. The sun shining directly into the camera obscured one incident.


WSDOT also has removed about 12 meters (40 feet) of concrete barrier at other interchanges in the region and plans to do the same at the I-82/Hwy. 22 interchange, with video surveillance continuing to determine how the modification affects wrong-way movements.


"I think this study will lead to major innovations in the way we deal with the wrong-way problem," says Jim Mahugh, assistant traffic engineer for WSDOT's South Central Region and manager of the I-82/Hwy. 22 project. "Our best bet for preventing wrong-way incidents is to build into any system a combination of video surveillance and detection."


Mahugh says that a system could be modified so that once a wrong-way vehicle is detected, the video is transmitted to a traffic management center or a highway patrol dispatch center, where an operator then can monitor the incident and send an officer if necessary.


The second WSDOT project is at I-5 and Bow Hill Road, a rural area about 113 kilometers (70 miles) north of Seattle. When electromagnetic sensors embedded in the ramp pavement detect a wrong-way vehicle, the system performs three primary functions. First, two signs mounted on both sides of the northbound exit ramp begin flashing an alternating red-yellow "Wrong Way" message for several minutes. At the same time, a closed-circuit video camera and time-lapse VCR record the incident to help traffic engineers determine the cause of the wrong-way incident and develop measures to prevent future wrong-way crashes.


Dawn McIntosh, a WSDOT project engineer, was selected to lead the project. After collecting regional crash data, McIntosh developed a list of eight sites where wrong-way incidents were unusually high. The northbound I-5 off-ramp to Bow Hill Road was selected after review of 1997-2000 crash data revealed three wrong-way incidents, one resulting in a double fatality.


Despite a WSDOT engineering review determining the wrong-way warning signs as adequate for this intersection, the westbound Bow Hill Road traffic tends to turn southbound onto the northbound off ramp. Heavy vegetation and the lack of lighting tend to obscure views of the interchange at night, the time when most wrong-way crashes occur.


WSDOT is poised to begin testing another wrong-way detection and warning system at the I-90/161st Avenue Southeast interchange, just 32 kilometers (20 miles) west of where Klotz was killed. This project will use a Traficon Video Detection system, which consists of a camera installed on a signal pole. When the video detector is activated, a signal is transmitted to the message sign, which flashes a wrong-way message to the driver while the VCR records the incident.


After McIntosh reviewed the crash data in the Seattle metropolitan area, I-90 at 161st Avenue Southeast was selected because the evidence suggested that an injury wrong-way crash had occurred recently at the interchange.


WSDOT's studies will assess how successful these new systems are in reducing wrong-way crashes. Monitoring the incidents with cameras and VCRs will enable WSDOT to evaluate the effectiveness of the three types of systems and compare rural-to-urban applications. The studies also will help determine whether the incidents are caused by driver error or interchange deficiencies, or a combination of both. WSDOT intends to reassess those interchange locations not originally selected to determine whether signing and striping changes would help reduce wrong-way movements.


"There's a serious problem out there with respect to wrong-way crashes," he says, "and I always wanted to find ways to do something about it." Eckhart, who retired in 2001 after 37 years with FHWA, adds, "The detection equipment was out there; we just had to figure out how to apply it effectively to wrong-way prevention."


In a 1989 Caltrans study, Prevention of Wrong-Way Accidents on Freeways, (Report No. FHWA/CA-TE-89-2) Joyce E. Copelan found that driving under the influence of alcohol or drugs is by far the primary cause of wrong-way crashes. But she also examined the relationship between wrong-way movements and interchange designs and offered suggestions for interchange improvements.


This type of interchange is seldom a problem and is considered the most desirable as far as preventing wrong-way movements, especially if reflective markers and a double yellow stripe or other barrier is used on the overcrossing bridge to keep motorists on the proper side.


The two-quadrant cloverleaf, which developers prefer because it creates properties on the two opposite corners, is less desirable in terms of wrong-way movements. However, separating the on- and off-ramps can prevent movements, as can designing the orientation of the on-ramp for easy access; constructing a larger, better-lit opening for the on-ramp than the off-ramp; and constructing a curb nose between adjacent ramps.


This interchange, though considered a good design, presents some potential problems. Motorists occasionally mistake an off-ramp for a frontage road located parallel to the ramp, and drivers can mistakenly turn left from the over-crossing street on to the off-ramp. An island constructed to partially overlap the off-ramp can prevent this from happening. Proper guide signing and direction pavement arrows are important to direct motorists to the correct lane for left turns on the freeway. Pavement markers also can be installed to direct drivers to the on-ramp entrance and, if space permits, a left turn lane may be provided.


Good signing is extremely important in this type of interchange. Wrong-way movements can occur if the guide signing does not clearly indicate a safe route for the driver to enter and exit the freeway.


Buttonhook ramps can be very susceptible to wrong-way movements. Problems can be minimized, however, using signing and a clear separation of the on- and off-ramps. The nose may be reconstructed and the on-ramp made wider and better lit than the off-ramp.


Incomplete and partial interchanges can present problems. The I-82/Hwy. 22 interchange in south-central Washington State is a classic example. The interchange was designed originally as a diamond, but the on-ramp in the northwest quadrant was never constructed. Instead, a loop ramp (partial cloverleaf) was constructed in the northeast quadrant. This configuration eliminates a heavy left turn and makes it into a much safer right turn. However, the design lends itself to more wrong-way entrances. Most of the interchange's wrong-way movements, about 66 percent, occur on the loop ramp.


Interchanges with short sight distance at the decision point have a disproportionate number of wrong-way movements. These locations lack some of the visual cues, such as headlights of oncoming vehicles, that alert wrong-way drivers that they have made a mistake.


WSDOT isn't the only State DOT currently researching and experimenting with wrong-way detection and warning systems. The Texas Department of Transportation is considering the possibility and feasibility of performing a research project beginning in fiscal 2003 that would examine potential wrong-way countermeasures. 2ff7e9595c


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