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myredracer's avatar
myredracer
Explorer II
Aug 17, 2017

Curious - gov't source for bridge lane width in WA state?

Just a general curiosity question...

Drove up the west side of Puget Sound yesterday along the 101. What a wonderful drive (highly recommended). There's a pair of old bridges at Hamma Hamma river that are short but have pretty dang narrow lanes.

Have driven on 101 there numerous times but at one of the bridges, a FW happened to be coming in the opposite direction at the exact same time. I always just keep our TT firmly planted in the center of the lane and keep going in instances like this - no big deal. The other driver actually stopped until we passed otherwise we would have passed at the exact same moment on the bridge. Can't recall the posted speed limit at that particular section of road but was probably 25 or 30 mph.

I know some drivers get nervous about passing oncoming traffic, especially in places like narrow bridges. This pair of bridges could be one of the narrowest I've crossed anywhere with the TT in tow. For those who know it, makes the Deception Pass bridge seem like a cakewalk in comparison. I would assume that lane widths anywhere have a standard min. width so that even the widest of vehicles like say logging or semi trucks can safely pass and if not, there'd be warning signage.

Is there a government or other source for lane width on bridges in Wa. state? What about other states for that matter? Or maybe what about narrow tunnels? I would have liked to have pulled over and measured the width of the lanes for fun, but no easy spot to do that.

This photo doesn't do justice to how tight it is. Maybe it's the proximity of the solid white line to the bridge structure that spooks some drivers.

  • wnjj's avatar
    wnjj
    Explorer II
    PawPaw_n_Gram wrote:
    The effective width of the lanes will be between 9' 4" and 9' 8" due to the striping of the roadway. Probably closer to the lower number.

    At least the striping won't damage your vehicle. The width from the center to the outside structure is the important number.

    If you all think that bridge is fun, try crossing the Columbia River at Hood River. It's 4400 feet long, steel grate decking and 9' 4 3/4" from the center to the guardrail. That's not a lot of room. I've towed an 8' wide snowmobile trailer over it a few times. You spend the whole time watching forward, then glancing back in your mirror to see your trailer almost rubbing the rail and making constant small adjustments. There is no "making the oncoming traffic wait."
  • rhagfo's avatar
    rhagfo
    Explorer III
    PawPaw_n_Gram wrote:
    The effective width of the lanes will be between 9' 4" and 9' 8" due to the striping of the roadway. Probably closer to the lower number.

    Finally Time wrote:
    Whenever I go through these bridges I put my left wheels on the other side of the double line. The bridges are short enough that it only takes seconds to cross them.


    The narrowness is somewhat perceived, I have seen loaded log trucks pass on these bridges. It is much like the perceived narrowness of the bridge on 99W going into McMinnville, OR. It is all about knowing how wide your load is, I see so many small cars cross over the center line on the 99W bridge when in the right lane. I never cross that center line pulling our 5er which is 8'-4" at the body.
    Taking your half out of the middle can get you a ticket for crossing the center line.

    On Edit: Those bridges in the past were also lower than they are now, if you look closely at the picture in the link, you can see light patches on both sides at both ends, where they removed additional cross braces.
  • Finally Time wrote:
    Whenever I go through these bridges I put my left wheels on the other side of the double line. The bridges are short enough that it only takes seconds to cross them.

    Yah, but is that real seconds, or 'Olympic Time Warp Seconds", looking at the distance, how long could if possibly take to drive from Quillecene to Lilliwaup ?
  • Whenever I go through these bridges I put my left wheels on the other side of the double line. The bridges are short enough that it only takes seconds to cross them.
  • The effective width of the lanes will be between 9' 4" and 9' 8" due to the striping of the roadway. Probably closer to the lower number.
  • Old-Biscuit wrote:
    Hamma Hamma River 'Rainbow Arch Bridges' info.
    Built 1924...20' Width/150' Span


    Thanks! Interesting website and will have to browse through it.

    That info. says the lanes would be 10' each. Sure *seems* a lot narrower than that. Makes sense with all the big logging and other trucks thundering regularly through there. No need for anyone to worry and slow down or stop.

    Maybe it's a psychological/optical illusion thing with the bridge structure so close to the curb side line.
  • I went over that bridge a couple months ago, and didn't find it challenging, though from several things, I suspect the bridge was built before WWII with 7 1/2 to 8 foot wide lanes. Certainly not more commmon 9 1/2 ft lanes.

    I've not found any source that list lane width almost anywhere in the US.

    I've gotten out and checked many places with my tape measure.

    I find that many, or most, people towing and driving RVs do not know their vehicle width and height.

    They take the mfr specs as gospel.

    My truck with the towing mirrors out is 8' 9 1/2" wide.

    My 8' wide TT is 8' 5 3/4" wide to the outside of the awning.

    I've measured friends rigs. I've found high end 5ers that are 8' 11" wide and 13' 11" high.

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