TACOMA, Wash. — Drivers who use Interstate 5 through Tacoma should prepare for some changes as the Washington State Department of Transportation (WSDOT) nears the finish line on a two-decade project to widen the interstate.

  Starting this weekend, crews will begin shifting a lane of southbound traffic onto a new bridge over the Puyallup River.

  From 11:59 p.m. Friday, June 18 through 11:59 p.m. Sunday, June 20, the following will close around-the-clock:

  Southbound I-5 exit 135 to Portland Avenue, northbound SR 167 and Bay StreetPort of Tacoma Road on-ramp to southbound I-5Southbound I-5 temporary collector-distributor lane

  Detour routes will be posted to direct drivers to the new bridge, which has seismic upgrades, WSDOT said.

  All southbound traffic will be shifted to the new bridge in a few months, a final chapter in the 20-plus year I-5 widening project.

  The old bridge will soon be demolished and equipment to take it down is already in place.

  By fall, new HOV lanes from the Fife curve to the Yakima Street overpass in Tacoma will open, WSDOT said.

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