Congress has approved another stopgap authorization for airport construction grants and other Federal Aviation Administration programs. The latest extension, which gained final congressional approval on March 26, will keep Airport Improvement Program funds flowing through April 30. The measure is the 12th FAA extension since Sept. 30, 2007, when the last multiyear aviation law expired. The new one-month stopgap gives Congress time to work on a new long-term FAA bill. When lawmakers return from a two-week spring break, they can begin to reconcile the two-year, $35-billion FAA authorization the Senate passed on March 22 and the three-year, $53.5-billion bill the
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.