Special Reports

Bridge update: Dec. 18

Construction this week on the new Tacoma Narrows bridge:

Tacoma Narrows Constructors is still trying to come up with a source for replacement wire for the main cables. Some of the wire has been found to be corroded.

TNC’s top executive, Manuel Rondon, spent last week in Japan, trying to get subcontractors Nippon Steel, Kawada Bridge and South Korea’s Kiswire to break into their production schedules and produce more wire quickly.

TNC also is in touch with a wire manufacturer in England.

Local crews sorting through stockpiled wire near the Tacoma anchorage have found at least 900 coils of wire, or about 3,600 miles, that are too corroded to use. They’re separating it from the rest and hauling it off site.

Chemical labs hired by TNC and the state are continuing their tests on the remaining wire, taking samples to assess how much zinc coating remains. Wire that is only lightly corroded is being cleaned by pressure washing and brushing with stainless steel brushes.

Meanwhile, cable-spinning crews finished strands 10 and 11 (of 19) on the south cable last week and this week will work on 12 and 13.

If the good wire holds out, they should finish the south cable by mid-January. The north cable will wait until more wire arrives.

Project engineers are considering the possibility of missing the state’s May 7 deadline for having the first deck section in place, in which case they will need to have catch-up plans ready.

Elsewhere on the project, retrofit crews continue their work inside the east anchorage of the 1950 bridge, strengthening it to meet current seismic standards.

Landscapers will be working throughout the project this week, but especially in the vicinity of a large retaining wall on the Tacoma side.

Rob Carson, The News Tribune

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