Study Confirms J-Turn Functionality
COLUMBIA - A MoDOT representative says the findings from a J-turn Study by the University of Missouri confirms the functionality of J-turns from a safety perspective.
MoDOT began adding J-turns in Missouri in 2007 and have continued to add them as recently as 2012. The J-turns in Columbia were constructed as a part of MoDOT's Route 63 and Route H interchange project.
John Miller is the traffic safety engineer for MoDOT's Central Office. He said the agency wanted to know if the J-turns were working from a safety perspective.
The study showed overall, there were safety improvements. The addition reduced fatal crashes by 100 percent and cut injury crashes in half. The addition also showed an angle reduction, eliminating the chance of a T-bone crash.
Miller said MoDOT wanted to begin installing the J-turns to reduce the angle collision, or T-bone crash caused by a crossover movement.
Miller said, "The design is built literally to eliminate that potential. So we're not putting them in for really many reasons other than reduction of those types of collisions, which are really severe."
Miller said most peoples concerns come from a lack of knowledge on how to properly execute a J-turn.
The proper way is to merge into the added deceleration lane until drivers come to the turn. At that point drivers are advised to make a safe U-turn maneuver and accelerate to the speed of traffic. Then, they're advised to merge into traffic and continue down the road.
Despite the evidence that shows the major safety benefits of the addition of the J-turns, some drivers are still not in favor of them.
John Miller said that most of the complaints he hears come from the fact that it is a bit of an inconvenience.
He said, "Again your making someone go right to go left and that just seems odd to people."
The survey conducted by the university showed people's general concerns were merging difficulty after the U-turn, insufficient U-turn radius to accommodate large vehicles, and general driver uncertainty and improper use of acceleration and deceleration lanes.
Moving forward MoDOT hopes to continue to add more J-turns. They are planning to add one in the Atlanta, Missouri area at Highway 63. They are also discussing adding one in Clark.