Related Links: P3 Bug Spreading Among U.S. Transit Builders Amid Labor Controversy, Dulles Metro Work Carries On After five years of construction and a long string of controversies, northern Virginia's $5-billion Silver Line rail project hit a major milestone with completion of the 11.6-mile first phase. Built by the Metropolitan Washington Airports Authority (MWAA) and operated and maintained by the Washington Metropolitan Area Transit Authority (WMATA), the $2.9-billion segment became operational on July 26, providing a long-sought light-rail extension from the existing Metrorail system to the burgeoning edge city of Tysons Corner, the planned community of Reston and the surrounding
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.