Crews from Tri-State Construction, Inc. will begin a three-month project today constructing noise barriers along State Route 16’s eastbound span of the Tacoma Narrows Bridge.

The noise barriers will help reduce the sound, which nearby residents say is similar to a zipper opening — but much louder. This sound can be heard an average of 40,000 times a day, when cars travel over the expansion joints on both ends of the bridge. The noise has been one of very few complaints by nearby residents about the one-year-old span that opened to traffic in summer 2007.

Engineers hope to zap the zipper sound with noise-absorbent panels placed on the sides of the bridge anchors. These panels will also be placed on four noise-barrier walls built on top of existing traffic barriers alongside the bridge. The noise walls are designed to mimic the geometric shape of the nearby anchorages.

Construction should be complete by the end of the year.