Work is to begin in mid-August on a $3.4-billion, 1,000-mile crude-oil pipeline from northern Canada to Superior, Wis., says Canadian owner Enbridge Inc., Edmonton, Alberta. Enbridge is burying a 36-in. pipe that will carry 450,000 barrels of crude oil daily, with a 326-mile U.S. route running from North Dakota to Wisconsin. The project will run parallel to another 20-in. pipeline that was constructed in 2009. The project was awarded to U.S. Pipeline, Houston, and Precision Pipeline of Wisconsin.
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.