June 17, 1958: The Ironworkers Memorial Second Narrows Crossing Collapses

The Ironworkers Memorial Second Narrows Crossing, also called the Ironworkers Memorial Bridge and Second Narrows Bridge, is the second bridge constructed at the Second (east) Narrows of Burrard Inlet in Vancouver, British Columbia, Canada. Originally named the Second Narrows Bridge, it connects Vancouver to the north shore of Burrard Inlet, which includes the District of North Vancouver, the City of North Vancouver, and West Vancouver. It was constructed adjacent to the older Second Narrows Bridge, which is now exclusively a rail bridge. The First Narrows Bridge, better known as Lions Gate Bridge, crosses Burrard Inlet about 5 miles west of the Second Narrows.

The bridge is a steel truss cantilever bridge, designed by Swan Wooster Engineering Co. Ltd. Construction began in November 1957, and the bridge was officially opened on August 25, 1960. It cost approximately $15 million to build.

The bridge is 1,292 metres (4,239 ft) long with a centre span of 335 metres (1,099 ft). It is part of the Trans-Canada Highway (Highway 1).

On June 17, 1958, as a crane stretched from the north side of the new bridge to join the two chords of the unfinished arch, several spans collapsed. Seventy-nine workers plunged 30 metres (100 ft) into the water. Eighteen were killed either instantly or shortly thereafter, possibly drowned by their heavy tool belts. A diver searching for bodies drowned later, bringing the total fatalities for the collapse to 19. In a subsequent Royal Commission inquiry, the bridge collapse was attributed to miscalculation by bridge engineers. A temporary arm, holding the fifth anchor span, was deemed too light to bear the weight.

http://en.wikipedia.org/wiki/Ironworkers_Memorial_Second_Narrows_Crossing