The double-deck Alaskan Way Viaduct will cause a disaster in an event of an earthquake in Seattle. The viaduct goes over the Great Northern railroad tunnel that was built in 1905 and it suffered no damaged at all during the 2001, 6.8 Nisqually Earthquake. Tunnels are safer during an earthquake. The Washington State Department of Transportation says earthquake vulnerability was the primary drive behind replacing the viaduct with a new, modern tunnel.
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