The Port of Miami Tunnel is the first large-diameter road tunnel ever constructed in Florida with the use of a tunnel boring machine (TBM). The project was complex, first and foremost, because of its scale: it involved excavating two 1.2-kilometre undersea tunnels to form a four-lane road, creating four floodgates, widening an 800-metre stretch of MacArthur Bridge by 6 metres and constructing an interchange to join up with the port’s existing road network.

The project, partly financed by Federal funding, was subject to strict requirements on a social level, and employment opportunities were given as a priority to local people, making the construction site a particularly cosmopolitan place. The French and American teams complemented each other well, one of the project’s key success factors. On site, a variety of qualifications and a mix of cultures – American, Latino and European – meant that some compromises were needed so that all the teams could work efficiently together. More than 2,000 training sessions were held to raise all site workers’ awareness of issues such as safety.