In another congressional reaction to the Gulf Coast oil spill, six Senate Democrats from the West Coast have introduced a bill that would permanently ban new oil and gas drilling off the shores of California, Oregon and Washington state. The measure, introduced May 13, would reinstate--only for the West Coast--a longstanding congressional and White House prohibition on Outer Continental Shelf oil and gas exploration. That nationwide drilling ban had been lifted in 2008. The bill was sponsored by Sen. Barbara Boxer (Calif.) and was co-sponsored by her California colleague Dianne Feinstein, as well as Sens. Jeff Merkley and Ron Wyden
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.