DALLAS — High-occupancy vehicle (HOV) lanes — generally open to vehicles with at least two passengers — have become a fixture on many urban freeways. However, according to recent research, adding HOV lanes may lead to more accidents. In an effort to improve air quality and get more people moving on crowded highways, the HOV lane miles in the U.S. have quadrupled since 1990 to 2,500 miles nationwide. But, according to a study by the Texas Transportation Institute, the rate of accidents involving injuries increased as much as 56 percent for stretches of Dallas freeway that have HOV lanes adjacent to regular lanes without a concrete barrier separating them. The Texas study relied on before-and-after crash data from highways where HOV lanes were added in the 1990s. Researchers at the Midwest Research Institute also found accident rates rose 11 percent in several Southern California locations where HOV lanes were added, lanes narrowed, or both. After learning about the Dallas data, the Maryland State Highway Administration re-examined accident data for a stretch of I-270 with HOV lanes outside of Washington, D.C. The accident rate was twice as high as the statewide average. Federal Highway Administration officials say the findings of the Dallas study shouldn’t necessarily be generalized to other regions. Another national study is planned on the safety of HOV lanes this year. California, New York, and seven other states are spending $200,000 and plan to produce a handbook for transportation planners on the safest designs. Click here to view the new study

Originally posted on Fleet Financials