Photo by Daniel Azoulay. Courtesy Bouygues Civil Works Florida On May 6, the PortMiami tunnel project's 380-ft-long tunnel-boring machine completed the final bore of two 4,200-ft-long tunnels. The $1-billion project is targeting an August 2014 completion. Related Links: Port Of Miami Tunnel Project Features Big Challenges A Gigantic Turnaround for a Giant Tunneling Machine Tunnel crews with Bouygues Civil Works Florida completed the last leg of mining for the second of two 4,200-ft-long tunnels for the $1-billion PortMiami tunnel project. On May 6, the project's 380-ft-long tunnel-boring machine—nicknamed Harriet—broke through for the last time, landing back on Watson Island, where
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.