Architects are calling the third version of the popular green-building rating system, Leadership in Energy and Environmental Design, a significant improvement over earlier releases. LEED 2009, which covers new construction, schools, core and shell, commercial interiors and existing buildings, “is a step forward,” says Greg Mella, a principal of SmithGroup, Washington, D.C., and a member of the American Institute of Architects committee on the environment. Under LEED 2009, rolled out late last month by the U.S. Green Building Council, credits are standardized on a 100-point scale. Credits also have been reweighted. Mella deems that important because it recognizes the connection
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.