Three Kentucky intersections—one in Marshall County and two adjacent intersections in McCracken County— suffered from a high percentage of angle collisions. To protect the safety of those on the road and decrease crashes, the state of Kentucky called on PRIME AE to design a solution. Relying on a long-standing and trusted relationship, Kentucky awarded our team with the third Highway Safety Improvement Program (HSIP) contract to convert the intersections to Restricted Crossing U-Turn (RCUT) intersections, also known as J-turn intersections.
The complexity of the project required a multi-faceted design solution to keep traffic flowing while curtailing collisions. Because of free-flowing mainline traffic and additional sight distance required for heavy vehicles using the intersection, more time was needed for trucks to complete the U-turn maneuver and reach a safe speed. For the two intersections in McCracken County, the U-turns also needed to be located so that sight distance for both was not impeded by the adjacent U-turn point. We designed the loons with radii to accommodate heavy vehicles while allowing all work to be completed within existing right of way.
Median islands were designed to accommodate large vehicles, while still providing channelization to prevent vehicles traveling in the wrong direction through the RCUT. Striping, signing, and drainage design rounded out the RCUT plans.
The highly complex project was assigned at the end of September, the preliminary review meeting was held in early December, and final plans were submitted the following April — a span of only six months. Construction was completed and all three RCUTs were opened to traffic only two years after initial assignment, making drivers in Marshall and McCracken counties safer on the road.