Wind, Waves Cripple 520 Bridge -- Major Route Across Lake Washington Could Reopen Sometime Tomorrow

The Evergreen Point Floating Bridge was damaged, and the drawspan could not be closed, after it was opened this morning to relieve pressure from high wind and waves.

Closing the bridge, a main east-west artery across Lake Washington, was like applying a tourniquet to traffic. The rush-hour commute immediately congealed throughout Seattle and the Eastside.

Bridge officials said it could take at least 24 hours to make repairs.

"If we really got lucky, we might make it open by rush hour tomorrow morning," said Pat Moylan, bridge superintendent. "But realistically, it might be tomorrow afternoon."

Traffic to the bridge was halted at 5:58 a.m. to open the draw span. State Department of Transportation guidelines call for the draw span in the middle of the bridge to be opened whenever there are wind gusts of more than 40 mph for 15 minutes.

Early-morning commuters on the bridge before it closed said it was a treacherous crossing, with the bridge rocking and waves sweeping over the roadway in a solid wall of water.

The bridge was last closed on Dec. 13, 1995, when another storm battered the area.

Damaged during this morning's storm were rollers used to slide movable sections at the draw span, said Bill Southern, a spokesman for DOT.

To open the bridge, the middle draw spans are lifted with hydraulic jacks and the two center pontoons slide back over heavily greased rollers under those raised sections.

Archie Allen, assistant superintendent at the DOT maintenance shop in Bellevue, said the vertical roller assembly had cracked, as had rail sections on the top of the pontoons. One piece of the broken assembly was lifted onto the bridge deck with a crane, while the other piece remained inside the bridge.

To get to that broken piece, Moylan said a 6,000-pound beam would have to be removed, after first removing and replacing 17-foot-long bolts. Crews said it's a tricky procedure, with dry ice used to shrink fittings into place, and made trickier by the bad weather.

"We're going to give it our best shot. We're used to working in tight places with heavy loads," he said.

To further complicate repairs, the damage was on the west side of the drawspan, while the bridge-maintenance shop is on the east side.

"Unfortunately, we're on the wrong side of the lake," said Allen, adding that replacement parts would have to be trucked over the lake on Interstate 90, and crews would then have to approach the bridge from the west.

The 36-year-old bridge carries 100,000 vehicles a day. It's not just another ribbon of freeway, but a complex mechanical device.

Modern design standards call for such bridges to withstand steady, 92-mph winds. But last year, state engineers concluded it would be too costly - $600 million to $900 million - to upgrade the Evergreen Point bridge to those standards and instead believe it should be replaced.

Meanwhile, they plan to strengthen the bridge this summer, though that still won't make it strong enough to have remained opened during today's storm, Allen said.

Two factors make the Evergreen Point bridge especially susceptible to wind - its extreme length and the long stretch of open water from the bridge southward, said Myint Lwin, former state bridge-engineering supervisor.

At 7,600 feet in the floating section, it's one of the longest floating bridges in the world. The two I-90 bridges are 5,600 and 6,600 feet long, and the Hood Canal floating bridge is 6,500 feet long, Lwin said.

The Hood Canal bridge is opened to relieve wind pressure four to six times a year, but remained open to traffic last night and today because wind speeds there didn't cross the safety threshold of sustained, 40 mph gust for 15 minutes.

One of the last major disruptions on the Evergreen Point Floating Bridge was in the Jan. 20, 1993, Inauguration Day storm that tore loose several of the 58 cables that anchor the bridge to the lake floor.