Acting to remove a stumbling block hindering the development of offshore renewable-energy projects, Interior Secretary Ken Salazar and Federal Energy Regulatory Commission Acting Chairman Jon Wellinghoff on March 17 announced an agreement on the roles of their respective agencies in approving such projects. Under a memorandum of understanding soon to be drawn up by their staffs, the Dept. of the Interior will be responsible for licensing offshore wind farms and FERC will have “primary responsibility” for licensing hydrokinetic, or ocean-energy, projects on the Outer Continental Shelf. The turf tussle has held up such projects since the language in the Energy
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.