By Mark Edward Nero
The reconfiguration of Pier 4 at the Port of Tacoma, which consists in part of redeveloping it to allow larger containerships to berth, is taking shape on the General Central Peninsula in the South Harbor.
Since awarding the contract to Manson Construction Co. and launching the first phase of the project in May 2016, the 1,724-foot pier nears its halfway mark, says the Northwest Seaport Alliance, the marine cargo operating partnership between Tacoma and the Port of Seattle.
Crews are working heavily on pier construction and installing underground utilities, including electrical, communication, sewer and stormwater treatment, according to the Seaport Alliance.
In February, Manson wrapped up the first phase of the pile driving, which set up the foundation for the structure that could serve two 18,000-TEU container ships once completed.
“Bigger ships require bigger cranes, and bigger cranes require a stronger foundation to evenly distribute the load,” Port of Tacoma Senior Project Manager Trevor Thornsley said. “Building the pier is all about providing enough support to handle the heavy cranes and the heavy load of the trucks, straddle carriers and the equipment that run on the pier.”
Each pile, varying from 70 to 170 feet in length, is driven underwater in a neat row formation, and the segments are then bound together with rebar and concrete to create a thick platform called a pile cap.
Once pile caps are built, the crew places 25-foot-wide deck panels between them and fills any gaps with more concrete. At the end of the project, the pier will be covered with three to six inches of pavement.
The second phase of pile driving is slated to resume in July, with the completion of the full project anticipated for a spring 2018, according to the Seaport Alliance.