SHINE — The Hood Canal Bridge will be closed most of the night during four days in early May to facilitate the repair of the western draw span of the floating bridge.

As the repairs are being made, state Highway 104 over the Hood Canal Bridge will be closed for a minimum of four nights beginning May 7.

During those days, the roadway over the bridge will be closed to traffic from 8:45 p.m. to

10:45 p.m., 11 p.m. to 1 a.m. and 1:15 a.m. to 3:45 a.m.

The repair schedule allows for only three 15-minute intervals in which motor vehicles will be allowed to cross the bridge during each seven-hour nightly closure.

“With this repair schedule, we can reduce the impact on drivers by allowing any backed-up traffic to flush through every two hours or so,” said Kevin Dayton, state Department of Transportation regional administrator.

“Compared to closing the bridge for seven hours a night and asking drivers to use a 130-mile detour, we feel it’s not a bad option.”

The work is weather-dependent and will carry over to the following weeks, if necessary.

Repairs are necessary, he said, because of the “daily grind” — the wind, waves and tide changes.

Although the eastern half of the floating bridge was replaced in 2009, the 30-year-old western half is showing signs of wear in key components of its draw span.

Divots in the 1 1/2-inch-thick steel plates running the length of the draw span make it difficult to open the west half of the bridge, Dayton said.

The plates protect the pontoon’s concrete from 4-foot-diameter steel rollers, which guide the draw span as it opens and closes.

The repairs, which must be made with the draw span open, involve welding low spots in the guide-roller rails, Dayton said.

“The draw span is closed 99 percent of the time, and the points where the rollers and the plate meet are exactly where the rub is taking place,” said Dayton.

“With all that grinding, it’s kind of like our bridge has developed a bad hip, and we need to repair it.”

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