As state transportation agency chiefs gathered for their annual winter meeting in Washington, D.C., they received some encouraging news from Congress on highway and transit funding for the short term, but not as many answers as they had hoped about the murky longer-range legislative picture. During the American Association of State Highway and Transportation Officials’ legislative briefing on March 2-4, Congress cleared—and President Obama signed—a bill that extends highway and transit authorizations for seven months, the seventh stopgap since the last multiyear measure lapsed in September 2009. Also enacted while the meeting proceeded was a temporary appropriations bill to keep
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.