TBM cutting head face. Photo courtesy of Port of Miami Tunnel[/caption] The $1 billion dollar tunnel project to provide direct access between the Port of Miami and I-395 and I-95 reached a major milestone as the TBM (tunnel boring machine) broke through a stone slab on Dodge Island, completing the first of two tunnels under Biscayne Bay. The project will provide a more efficient traffic flow out of the port and relieve downtown Miami of significant traffic, especially port-bound trucks. This first phase ended seven months of boring. The TBM, named Harriet, in honor of Harriet Tubman, is four stories tall and as long as a football field. It will now be partially disassembled, turned around, and reassembled to begin boring the return tunnel to Watson Island. Revere designed and built the controls for the conveyor system which removes the paste-like spoils from the tunneling process.
Watson Island showing tunnel pit as of May 2012. Photo courtesy of Miami Tunnel Project