Six more columns on the new Highway 520 floating bridge are defective, but contractors will replace them at no cost to taxpayers, a state manager said.
Julie Meredith, program director for the six-lane bridge now under construction, disclosed the findings Wednesday while briefing a joint committee of state legislators in Seattle.
These columns are attached to the top of Pontoon W, the giant east endpiece. One column was already broken and rebuilt in December, after the concrete surrounding a steel reinforcing cage was found to be thinner less than the required 1 ½ inches.
The state learned this spring that six more were deficient but didn’t say so publicly. Then on Friday, contractors from the Kiewit-General-Manson team said they would rebuild the columns, rather than brace them, Meredith said. The piece is now moored in the Duwamish River. Column replacement will occur either there or on Lake Washington in the next four to six weeks, she said.
The other three of 10 columns were built correctly, she said.
Meanwhile, cracks in Pontoon W have were sealed this summer at a Harbor Island drydock, Meredith said. The state Department of Transportation is negotiating to reduce a possible $378 million cost of design errors and delays in the $4.1 billion highway replacement.