The U.S. military’s multibillion-dollar program to build up facilities and infrastructure on the Pacific island of Guam to handle new troops could face scope and schedule changes, based on conclusions of the program’s final environmental review, released on July 28. But local officials on the island remain concerned about the military’s growing island footprint and impacts to cultural and ecological resources. Guam’s Apra Harbor is planned as the site for deep-water port facilities to accommodate nuclear carrier ships, but the Navy is deferring a decision on a specific location until further study of likely environmental damage. The military’s new 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.