When our transportation engineers were challenged to make traffic flow more smoothly and safely through the US 68 (Harrodsburg Road) and KY 4 (New Circle Road) intersection, we turned to a creative, cost-saving interchange design: the Double Crossover Diamond (DCD). The award-winning solution decreased accidents by 45%, improved traffic flow, and incorporated shared use paths for pedestrians and cyclists.
We performed a detailed traffic analysis and nationwide research to determine the best widening solution possible given existing constraints. What began as a major roadway widening turned into the first DCD in Kentucky, and only the sixth in the nation. We were entrusted with the preliminary and final roadway design, traffic analysis, lighting and signal design, and public outreach. The design also met KYTC’s goal to provide a safe bicycle and pedestrian pathways through the interchange and seamless access to the other non-motorized facilities. Not only did the DCD reduce congestion and double capacity in an area that accommodates more than 35,000 vehicles per day, but it also offers the safety and capacity of a “full-scale” fix without the full-scale price.