The U.S. Environmental Protection Agency declared on March 2 that the Gowanus Canal will be added to the list of federal Superfund cleanup sites. The heavily polluted canal runs through an old industrial sector in the New York City borough of Brooklyn and empties into New York harbor. EPA’s decision will set in motion a $500-million, decade-long effort to clean up the former industrial canal, which EPA says is contaminated with PCBs, coal-tar waste, heavy metals and volatile organics. Mayor Michael Bloomberg (R) had opposed the EPA designation, fearing it would endanger real estate developement plans for the area. EPA
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.