The U.S. Army Corps of Engineers has started staged award of a $500-million-plus contract for construction of the Gulf Intracoastal Waterway West Closure Complex in southeast Louisiana. It is expected to be the largest and most complex piece of the Greater New Orleans Hurricane and Storm Damage Risk Reduction System. Included are extensive flood-wall systems, a 20,000-cu-ft-per-second pump station and two sector gates of about 225 ft and 75 ft in width, all built next to a federally designated “nationally significant” wetland, says Kevin Wagner, Corps senior project manager. On April 17 Gulf Intracoastal Constructors, New Orleans, a joint venture
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.