Founded on the banks of the Potomac River in 1749, Alexandria, Va., served as one of the busiest seaports in early U.S. history. So it wasn’t surprising that the team building a three-acre, mixed-use project on the waterfront in Alexandria’s Old Town area discovered a wealth of colonial artifacts during excavation. Still, archaeologists from the project team and the city didn’t expect to discover the remains of three mid-18th-century wooden ships at the $185-million Robinson Landing project site.
To help unearth the abandoned sailing ships—commonly used to shore up areas for docks in the 1700s—the team brought in a specialized vertical cutter post mounted on a base crawler machine, a machine that project officials say is not typically deployed in the MidAtlantic region. Using modern methods, the machine built a trench cutting and remixing deep (TRD) soil mix wall, a 21st-century shoring method, according to the project team.