For this design/build project, 2LMN partnered with Allard Excavation to modify the interchange of US 52 and SR 243 from a standard diamond interchange to providing roundabouts at the on/off ramps in Lawrence County Ohio. US 52 through the project area is a divided 4 lane interstate look-alike with on and off ramps leading up to SR 243 above. SR 243 is an existing undivided 4 lane highway in which the standard 4 leg intersections at each ramp terminal was modified into single lane modern roundabouts. The roundabouts are designed to accommodate mega-load hauling vehicles up to 200’ in length. Therefore, many of the typical “raised” curb features found at standard roundabouts had to be accommodating for this vehicle type. Wider shoulders and 2” tall curbing was used into order for these large vehicles to negotiate the roundabouts. 2LMN was the prime designer that would see SR 243 go from 2 lanes, down to 1 lane in each direction going through 2 roundabouts at the on/off ramps to US 52. The project included resurfacing, pavement replacement, new lighting, new guardrail, and post construction BMPs all to be kept within existing R/W. The project is slated to be fully constructed and opened in 2025 with the majority of construction taking place over the entirety of 2024.