Related Links: Gates Still Needed for Lake, Ex-Corps Head Says: Times-Picayune Letter to the Editor, June 2007 Corps Culpable for Flooding? Answers to the Accusations 2006 National Public Radio report: Why Did the 17th Street Canal Levee Fail? Dawson & Associates website tribute HeibergLt. Gen. Elvin R. "Vald" Heiberg III, who became, in 1984, the youngest U.S. Army officer to lead the Corps of Engineers since the 19th century but who also expressed some post-Hurricane Katrina regret over his role in the agency's earlier actions and decisions in construction of regional defenses, died on Sept. 27 in Arlington, Va., at
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.