Tacoma Narrows Bridge?-?Tacoma, Wash.
Kiewit was part of a joint venture that constructed the new Tacoma Narrows Bridge and retrofitted the existing Narrows Bridge. The structure is the first long-span suspension bridge constructed in the U.S. since 1964. This $615 million structure is 5,400 feet long and 78 feet wide, with a 2,800-foot main span and two 510-foot-tall towers. The new four-lane bridge opened to traffic on July 16, 2007. It carries eastbound traffic and connects Gig Harbor to Tacoma, running parallel to the existing Narrows Bridge.
Construction of massive caissons required more than 30,000 cubic yards of concrete for each base. The suspension system includes 20.5-inch-diameter main cables assembled from 5,500 tons or 18 miles-of steel wire. The toll facilities and adjacent highway improvements include approximately 500,000 cubic yards of roadway excavation and 300,000 cubic yards of embankment. The bridge consists of a high-occupancy vehicle traffic lane, a bicycle/pedestrian walkway, and a configuration for a future secondary roadway or transit deck.
A retrofit to the existing bridge included seismic upgrades, replacement of rails, removal of existing steel grates to portions of the existing bridge, and improvements to more than three miles of approach roadway.