Smallest Bridges

[Sykotyk]

I just had a general thought that I don't think we've delved into before. We all can talk about the tallest, longest, oldest, etc bridge. But, what about the smallest?

For instance:

A) What is the smallest suspension bridge (that's not simply decorative)
b) Smallest Through Truss bridge?
c) Smallest through arch bridge/arch truss bridge?
d) smallest draw bridge (height of rise--if not swing decks--or drawspan)?

I was down in Louisiana a few days ago clinching the state of parishes, and went over many draw bridges, some were surprisingly narrow and close to the waterway. Never really thought about it before.

I'm sure there's some culverts out there built as absurdly small bridges out there rather than placing a pipe, filling around with dirt, and paving over.

[agentsteel53]

there's about a 30 foot long suspension bridge crossing a stream in someone's backyard off 395 in Modoc County.  it supports a four foot wide walkway.  probably just a guy who likes tinkering.

[SteveG1988]

In my home town there is possibly a 6 or 7 foot long plank bridge across a lake.

http://maps.google.com/maps?q=browns+mills+NJ&oe=utf-8&client=firefox-a&ie=UTF8&hq=&hnear=Browns+Mills,+Burlington,+New+Jersey&gl=us&ll=39.974327,-74.573292&spn=0.001024,0.002626&t=h&z=19&layer=c&cbll=39.974327,-74.573292&panoid=po_ltdf_teZbL0ZcGcxy4g&cbp=12,196.53,,0,14.16

It crosses like a viaduct upto that section and is signed as "turtle Log bridge"

[Alps]

I've seen 20 foot (or less) pony trusses for people's driveways to cross the culvert next to the main road. There's a small suspension bridge in Alaska, actually on my site for AK 98, that only has a single pier it's so small.

[US71]

I just had a general thought that I don't think we've delved into before. We all can talk about the tallest, longest, oldest, etc bridge. But, what about the smallest?

For instance:

A) What is the smallest suspension bridge (that's not simply decorative)
b) Smallest Through Truss bridge?
c) Smallest through arch bridge/arch truss bridge?
d) smallest draw bridge (height of rise--if not swing decks--or drawspan)?

I was down in Louisiana a few days ago clinching the state of parishes, and went over many draw bridges, some were surprisingly narrow and close to the waterway. Never really thought about it before.

I'm sure there's some culverts out there built as absurdly small bridges out there rather than placing a pipe, filling around with dirt, and paving over.

You might check out Bridgehunter.com . I bet you can find your answers there.

[pianocello]

Does it count if the river is flooded? If the river gets high enough, it's very possible for the deck to be a few inches underwater, especially for those metal deck bridges.

[NE2]

Count how? Are you thinking that the water would shrink the bridge?

[andytom]

http://maps.google.com/?ie=UTF8&ll=45.682847,-122.526446&spn=0,0.005745&t=k&z=18&layer=c&cbll=45.682849,-122.526311&panoid=455gvjEUcs2ftnyO7Kh-cQ&cbp=12,249.66,,0,0

A pedestrian cable-stay bridge over Padden Pkwy east of I-205 in Vancouver, WA.

--Andy

[vtk]

Count how? Are you thinking that the water would shrink the bridge?

I think the idea is, the rising water would make the bridge's "height" go negative.

[NE2]

But the height is measured from land, not the water level.

[vtk]

But the height is measured from land, not the water level.

Not if it's a bridge over a waterway.

[NE2]

For boat clearance, sure. But for engineering purposes it has to be designed as if there were no water (leaving out floating bridges, which will rise with the water level anyway). Thus some of the country's tallest bridges are not that much above the surface of reservoirs.

Or at least that makes more sense than measuring from a possibly fluctuating water level. But my world and the real world don't always coincide.