The Restricted Crossing U-Turn Intersection (RCUT) project was recently honored by the American Council of Engineering Companies of South Carolina (ACEC-SC) with an Engineering Excellence Award in the Transportation category.
For this program, the South Carolina Department of Transportation (SCDOT) tasked STV with assessing improvements for the intersection of Moores Mill Road and Laughlin Road at US 76 in Marion County, SC, because that intersection, as well as several adjacent intersections, had a history of frequent and severe crashes. Most of the crashes were right-angle collisions. Prior to the onset of the project, traffic at the intersection was controlled by stop signs.
The goal of the project was to assess existing conditions, evaluate and develop alternatives, engage and communicate with the public, and develop a design solution for this site. The STV team evaluated three traffic control alternatives: signalization, a multi-lane roundabout, and an innovative “Superstreet” concept known as an RCUT. After carefully analyzing each alternative, the team determined that the safest, most efficient, and economical engineering approach that would minimize impacts to the public was the RCUT.
Thomas Mastillone, P.E., a civil engineer in STV’s Charleston, SC, office, was the lead roadway engineer.
RCUT designs reduce vehicular conflict points within an intersection by requiring cross-street vehicles to turn right onto the main road and then make a U-turn at a designated one-way median opening after the intersection. Vehicles can then either continue their left turn by driving straight on the main road or make a right turn onto the opposite minor road to complete the through movement. The RCUT design is a lower cost improvement that dramatically improves safety, has fewer right-of-way and utility impacts, and can be constructed in a fraction of the time compared to other alternatives. The RCUT at this location reduced intersection conflict points by nearly 50 percent without reducing travel speeds on US 76.