A 30-year-old construction worker from Collins, Mo., remains in critical condition at a Kansas City, Mo., hospital more than a week after he was accidentally swept 1.5 miles through a sanitary sewer pipeline in Raymore, Mo. Daniel Collins was working about 12 ft below ground in a sanitary sewer shortly after 8:00 a.m. on Oct. 12, when a torrent of raw sewage flowing at a rate estimated at up to 3,500 gal per min swept him more than 7,900 ft through the 27-in-dia sewer pipe. It is still unclear how Collins’ safety harness separated from its attached safety line when
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.