As Congress begins a short pre-election session, its must-pass list includes construction measures with Sept. 30 deadlines: appropriations for fiscal year 2011, which starts on Oct. 1, and a Federal Aviation Administration authorization that covers airport grants. A bill aimed at aiding small businesses also is advancing. With only a few weeks left before a congressional recess, action on other bills probably will be deferred until an expected lame-duck session. In that post-election session, Congress would face decisions on extending income-tax breaks, Build America bonds and surface-transportation program—all of which expire on Dec. 31. Other measures, including an energy bill,
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.