Port of Tacoma Commissioners today approved a $21.8 million contract to build the final piece of the Lincoln Avenue Grade Separation.

This freight transportation project includes an overpass to carry trucks and other vehicles over busy rail lines in the Tacoma Tideflats area.

The 2,200-foot-long overpass will add three lanes of roadway over four sets of railroad tracks. Truck queues at the current at-grade crossing can last up to 45 minutes behind trains serving the Port,s two main intermodal yards, according to Port officials.

The Port has completed three surface streets and relocated utilities to support the overall project. The final piece, the overpass itself, remained unfunded until the Port received $15.4 million in March from American Recovery and Reinvestment Act funds.

The $53.2 million project has received funding since 2002 from several local, state and federal sources. The Port expects to pay about $17.9 million of the total.

The Port received nine bids for the overpass construction, ranging from a high of $27.7 million to a low of $21.8 million, submitted by Scarsella Brothers Inc., of Kent. The low bid was about 10 percent lower than the engineers’ estimate of $24.4 million.

Construction is expected to begin in August or early September.