The nearly decade-long fight over whether to raze or rebuild the Alaskan Way Viaduct on Seattle’s waterfront is nearing a final decision. On Jan. 13, Washington Gov. Chris Gregoire (D) announced that she favors replacing the 55-year-old highway with a $4.25 billion deep-bored tunnel. King County Executive Ron Sims, Seattle Mayor Greg Nickels and Port of Seattle Chief Executive Officer Tay Yoshitani also support the plan. Elected officials have been debating whether to rebuild or replace the viaduct since 2001, when the double-deck freeway was damaged in an earthquake. A month ago, an advisory committee created to study design options
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.