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Video shows inspections revealing flawed anchor cables on 520 bridge

Video from beneath Lake Washington shows what inspectors saw as they drove a remote camera over the anchor cables on the new State Route 520 floating bridge.

In some spots, strands of steel cables have popped out.

In others, cables are twisted or bent.

Of 58 anchor cables, the state asked the contractor to replace 46.

"We wanted to make sure we had the longevity for the bridge so we wanted them replaced," said Steve Peer, of the Washington State Department of Transportation.

Peer sat down with KIRO 7 to talk about the cable problems after we filed a records request for documents, photos and video.

Underwater inspections in early 2016, before the bridge opened to traffic, revealed what WSDOT calls "anomalies" in the cables.

Despite the flaws, Peer said the cables were plenty strong to safely keep the bridge anchored in place, but the state wanted to make sure they lasted as long as possible.

The contractor covered most of replacement cost, with the state spending about a million dollars on the fix.

That cost was covered by contingencies in the project budget.

"This is a $1.5 billion bridge, and $1 million, while it's a lot, is not as much in comparison, especially when we want to deliver a bridge we want to last 75 years," Peer said.

Cracked pontoons early in the project added about $200 million to the cost of the bridge.

Peer said it's not entirely clear how the anchor cables were damaged, but it might have happened during installation.

The problem landed the new bridge on a national list of structurally deficient bridges, although when the list was published in December, most of the cables had already been replaced.

WSDOT did not notify the media about the cable problems, but did mention them in monthly construction reports found deep on the project website.