The in basket: Bruce Fields of Bremerton thinks the location of the wind socks on the old and new Tacoma Narrows Bridges could be more helpful.
“I used the bridge (recently) while it was very windy,” he said. “The east side wind sock was not indicating any wind in spite of the obvious blow going on. I was in a full-size pickup with canopy with a 40-foot tractor-trailer in front of me and beside me, all headed east.
“They should have a wind sock on both bridges on both ends as they can give a guide to the strength of the wind and gusts,” Bruce said.
“I had to gauge by the 18-wheeler in front of me.
“When the wind is strong as you pass the towers, the rigs swerve out and back into the wind load. I am sure at some wind angles they are shadowed and that is what I got last week but by putting them on the new bridge too, any wind direction should give us a read.
“The wind socks are perfect tools if they would work. When I got to the east landing the old bridge sock was laying strait down. It was shadowed from the south wind by the new bridge. It is a south wind there most of the time.”
And Tim Fisher writes, “At night the socks are above the street lights and can’t be seen at all. Any chance of a light that shines on the socks?”
The out basket: There is a wind sock at one end of each bridge, where vehicle traffic boards the span in each case. But there is a problem with their nighttime visibility, say Chris Keegan and Jon Moergen of the state’s bridge engineers.
Chris said Jon has a problem with locating the windsocks so that they are close enough to the shore to be seen before you get to the bridge and far enough out on to the bridge that they are away from the shore effect and react to the higher winds. “He had lights that did shine up at the windsocks, but these kept shorting out,” Chris said. “He is looking into putting reflective strips on the windsocks to enhance visibility. He is also looking at either solar-powered lights or wiring in lights on a pole that would shine directly on the windsocks.”
Chris also said, “Because of the distance from the tower of the new bridge to the wind sock at the east end north side of the old bridge, the tower would have a negligible effect on the windsock.”
Asked to explain what Bruce described, Chris said, “I would say the winds were gusting and when he got to the end of the bridge the wind had momentarily dropped off. Or the wind was directly out of the South. When that happens the south end (some of us call it the East end or Tacoma end) of the bridge is protected by the land mass. Whereas the towers have a negligible effect, the land mass has a noticeable effect on the speed of the wind.