Emergency underwater repairs will continue Saturday, March 10, as divers replace a second damaged State Route 520 floating bridge cable connection found on Friday.

As part of routine bridge inspections, Washington State Department of Transportation bridge engineers on Thursday discovered a damaged hardware connection on the west end of the floating bridge where one of 58 anchors ties the to the bed of Lake Washington. Working in water 30 feet deep, divers repaired that connection by Friday afternoon.

As a precaution, bridge engineers called for inspections of three other similar anchors and found the same problem on one additional connection at the far east end of the bridge. Two other locations were inspected and did not have the same damage.

On Friday afternoon, divers set up equipment near the east end of the floating bridge, where they will work in water 60 feet deep starting again Saturday morning.

The bridge remains open and safe to drive, but coincidentally closed for prescheduled weekend construction at 11 p.m. today. Construction crews will demolish an overpass in Medina and dig huge trenches across highway lanes in several locations on the Eastside throughout the weekend.

One-third of the floating bridge anchor cables are inspected every two years, and 15 of the 58 were replaced in 2010. Initially corrosion was suspected as a cause of the damaged anchor connections. While a final determination is pending, bridge engineers say it appears that the steel pin hardware connections were bent by forces produced by wind and wave action on the lake.

Repair work is preliminarily estimated to cost up to $60,000 and is expected to be completed as soon as Saturday.

Immediate repairs were necessary because engineers said connecting pins tying together anchor cables and anchors already had slid out of position. If a pin was forced completely out of position, separating the bridge and cable from the anchor on the lakebed, it would reduce the bridge’s ability to withstand large storms.