Repairs scheduled on the westbound Tacoma Narrows Bridge deck will require crews to close three of the four westbound State Route 16 lanes this Thursday night, Sept. 19.

At 8 p.m. on Thursday, Washington State Department of Transportation bridge maintenance crews will close the two left westbound SR 16 lanes across the Tacoma Narrows Bridge.  At 9 p.m., they will close a third westbound lane. The right westbound lane will remain open all night, as will ramps near the bridge. All three westbound lanes will reopen by 6 a.m. Friday, Sept. 20.

During the closure, crews will chip out small areas of concrete in the bridge deck to expose, repair and reinforce about six steel bars that have broken loose inside the deck. The bars were embedded in the deck’s concrete when the bridge was originally constructed in 1950. The deck has hundreds of such bars, whose purpose is to connect the deck to the bridge’s steel expansion joints. Occasionally, welds on the bars break due to metal fatigue caused by the daily pounding of traffic. When that happens, bridge maintenance crews either replace the bars or repair them. In this case, crews will repair the existing bars as well as install new bars to reinforce the area.

Similar work was done in 2011 when bridge crews repaired several bars in an adjacent lane