While the replacement of Seattle’s aging Alaskan Way Viaduct plods toward a definite construction start date, long-needed improvements are well on the road to completion on another of the city’s critical elevated structures. Photo: SDOT Spokane Street Viaduct gets a makeover in anticipation of bigger Alaskan Way Viaduct work. PCL Construction Services Inc., Seattle, has completed 257 drilled shafts for columns that will support the widening of the 3,000-ft-long Spokane Street Viaduct. One of Seattle’s five busiest roads, the viaduct carries up to 70,000 vehicles a day between Interstate 5 and the West Seattle Bridge and serves as a primary
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.