Operational Field Studies of Two Wrong-Way Signing Countermeasures

Most recent wrong-way driving (WWD) research has focused on quantifying the WWD problem and summarizing information about traditional and innovative countermeasures and mitigation methods, instead of evaluating the effectiveness of these strategies. Recent implementations of two wrong-way signing countermeasures in Texas provided Texas A&M Transportation Institute researchers the opportunity to assess the effectiveness of these strategies in actual operational environments. The first field study evaluated the effectiveness of WRONG WAY signs with flashing red light-emitting diodes (LEDs) around the border in San Antonio. The second field study assessed the effectiveness of lowered DO NOT ENTER and/or signs WRONG WAY in the Dallas area. Researchers performed a before-after evaluation with a comparison group to determine whether or not a meaningful reduction in WWD events was observed for both countermeasures. Researchers calculated a 38 percent reduction in the WWD events on the test corridor in San Antonio after the installation of WRONG WAY signs with flashing red LEDs around the border at all exit ramps in the corridor. Researchers also calculated a 56 percent reduction in WWD events after the installation of DO NOT ENTER and/or WRONG WAY signs at a lowered mounting height (2 ft). These reductions represent the conditions studied. Based on these positive findings, researchers recommend that agencies consider the use of these WWD countermeasures when they are deciding how to mitigate WWD events.