Located in downtown Newberry, South Carolina, the Boundary Street Bridge carries SC 34 over two active CSX railroad tracks and serves as a key connector for local residents and freight traffic. Originally built in 1957, the bridge was identified by South Carolina Department of Transportation (SCDOT) as structurally deficient, with low vertical clearance that no longer met current standards for commercial vehicles. STV provided structural design services to fully replace the aging structure and strengthen a critical segment of the region’s transportation network.
What challenges did STV address?
The project required replacing an outdated bridge within a constrained corridor defined by railroad operations, roadway curvature and a skewed alignment. The site also included a steep vertical curve and limited working space, which complicated both design and construction. Because the bridge was selected for an SCDOT pilot program evaluating decked girder technology, STV needed to incorporate an innovative structural system while ensuring compliance with safety and performance requirements.
What solutions did STV deliver?
STV designed South Carolina’s first decked girder bridge – a Type III girder system with a seven‑foot‑wide top flange – filled with Ultra‑High‑Strength Concrete to create a stiff, durable deck surface. This system accelerated construction and minimized field operations over the active CSX tracks. The final design included a single‑span superstructure, upgraded roadway approaches and MSE walls that improved safety and traffic operations while maintaining the site’s unique geometry. The approach leveraged innovation to reduce future maintenance and improve constructability.
How does this project benefit the community?
The replacement bridge improves vertical clearance, roadway safety and long‑term structural performance. It reduces freight limitations on a key route, enhances traveler safety and supports economic growth by strengthening regional mobility. As the state’s first decked girder bridge, it also advances SCDOT’s efforts to identify more efficient construction methods for future projects.
Key stats and accolades
- First decked girder bridge in South Carolina
- 7‑foot‑wide top flange
- 9.5‑inch haunch height
- 106‑foot total bridge length
- Part of SCDOT’s decked girder pilot study
