Carrying both commuters and water, tunnels have long snaked through the bedrock beneath New York City, but now the labyrinth is growing: Multiple projects are under way totaling nearly $2.5 billion, with several other tunneling jobs on the horizon. Photo: Launch Box Second Avenue subway’s first phase is a $350-million, four-year contract. “Everyone wants these projects done as soon as possible, so we have a flurry of underground activity,” says Gary A. Almeraris, vice president of Skanska USA Civil, Whitestone, N.Y., which has major contracts on three of the region’s biggest tunneling jobs. “This is good news for the New
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.