Related Links: Niche Products Emerge to Help Reduce Bird Deaths Minnesota Sports Facilities Authority National Audubon Society The National Audubon Society has lost its battle for a bird-friendly envelope enclosing the state-owned Minneapolis stadium, just starting construction for the National Football League's Minnesota Vikings. But the defeat, though deflating, has a silver lining, says Audubon. The group went public with its 14-month campaign against a transparent facade after the Minnesota Sports Facilities Authority refused to switch to bird-friendly fritted glass for the $975-million facility."While, ideally, we hoped to find a solution through collaboration, the decision of the Minnesota Sports Facilities
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.