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Dawson Forest Bridge

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Photo 

Photo taken by Ron Mayhew

View this photo on Flickr

Map 

Facts 

Overview
Abandoned through truss bridge over Etowah River
Location
Dawson County, Georgia
Status
Abandoned
Design
5 panel Pratt through truss
Dimensions
Total length: 80.0 ft.
Also called
Possibly called Hay's bridge
Approximate latitude, longitude
+34.36840, -84.16496   (decimal degrees)
34°22'06" N, 84°09'54" W   (degrees°minutes'seconds")
Approximate UTM coordinates
16/760713/3806647 (zone/easting/northing)
USGS topographic map
Matt
Inventory number
BH 53310 (Bridgehunter.com ID)

Categories 

A-frame portal (232)
Abandoned (1,371)
Dawson County, Georgia (6)
Georgia (386)
Owned by state (9,807)
Pratt through truss (3,166)
Pratt truss (5,658)
Through truss (9,205)
Total length 75-100 feet (4,795)
Truss (23,566)

Update Log 

  • August 31, 2012: Updated by Fmiser: Removed Railroad category
  • August 30, 2012: Updated by Fmiser: Changed design description to 5-panel Pratt, added length - which is approximate.
  • August 29, 2012: Updated by Luke Harden: Added related bridge
  • August 29, 2012: Updated by Fmiser: Changed positon data.
  • August 29, 2012: Updated by Don Morrison: Moved map pin to Blue Trail river crossing.
  • August 28, 2012: Updated by Fmiser: added more info on the design
  • August 28, 2012: Added by Luke Harden

Sources 

  • Luke Harden - lukemh9 [at] gmail [dot] com
  • Fmiser - fmiser [at] gmail [dot] com
  • Don Morrison

Comments 

Dawson Forest Bridge
Posted August 31, 2012, by Fmiser (fmiser [at] gmail [dot] com)

I'm removing the "railroad" category from this bridge. I am now convinced it was not used for the Lockheed nuclear site railroad.

The final point in convincing me is the terrain. I looked at the topographical data. From the bridge, the road north climbs much to steeply for a conventional railroad. The road south isn't quite as extreme, but still a serious slope for a railroad. The road to the east, however, is just exactly what I would expect. Some of the maps even label this one "Rail Road". The alignment effectively follows the contour lines.

So, for me the weak arguments against it being a railroad bridge are: it was built to early, the deck is too wide, construction is lightweight, and the other two railroad crossings were girders

Stronger arguments are: the map in "radrpt2002_dfw.pdf" shows the railroad ending south of the bridge, the various texts I found mention a railroad only between the reactor and the hot cell area which would not involve crossing at this bridge, and the alignment of the road crossing at the bridge could not be used for a conventional railroad.

I'm convinced. But if someone is equally convinced that it _was_ used by the railroad, and adds the category back in, I'm not going to fight it. *smiles*

Dawson Forest Bridge
Posted August 30, 2012, by Don Morrison

That was a very interesting bridge hunt.

I guess I made things confusing when I moved the map pin to the blue trail crossing instead of entering the coordinates I had arrived at.

Since the default map is a Google map, I couldn't see the bridge but could see the blue trail crossing.

Dawson Forest Bridge
Posted August 29, 2012, by Fmiser (fmiser [at] gmail [dot] com)

Andrew, a minor point about the bridge design description. This is a 5 panel Pratt because the end post to hip vertical counts as a panel.

And get used to the frustration of not being the fastest. Luke is _so_ fast he can update the page in less time than it takes me to reload it!

I'm not convinced it this bridge ever had the railroad on it. Based on the map in this PDF Andrew linked

http://www.gaepd.org/Files_PDF/gaenviron/radiation/radrpt2002_dfw.pdf the reactor is just south of this bridge and the railroad didn't cross the Etowah River here.

The map in this page http://www.advrider.com/forums/showthread.php?t=405686 shows this bridge as "existing". It doesn't distinguish between rail and automobile roads - but those two maps seem to match. None of the data that I'm seeing has the railroad north of the river, west of the horseshoe bend.

Dawson Forest Bridge - external confirmation
Posted August 29, 2012, by Andrew Pearce (drew458 [at] barking-moonbat [dot] com)

the coordinates we have are correct. 34.3683, -84.1650 is what is given by the Etowah River Water Trail Point Of Interest marker at mile 44.24, just west of that horseshoe bend:

http://etowah.secondsitellc.com/interactiveMap.php

and that POI links to this picture that I posted earlier today:

http://etowah.secondsitellc.com/DawsonForest.php?i=1

So ... good hunting everyone, well done! Found that bridge, the abutments for 2 others, and the Shoal Creek Rd bridge that was narrow gauge RR too [this is the Red trail/Blue trail/P7 road crossing] see 34.35605,-84.140089 in Bing, and see: DawsonForest005.jpg from

http://www.advrider.com/forums/printthread.php?t=405686&pp=100 (11-28-2008 4:05pm post)

4 bridges for the price of 1. Nice.

Drew

Dawson Forest Bridge
Posted August 29, 2012, by Andrew Pearce (drew458 [at] barking-moonbat [dot] com)

this link

http://northgeorgiamountainramblings.wordpress.com/

says it was a narrow gauge RR, and this canoeing brochure

http://dawsoncounty.org/uploads/files/parksandrecreation/Canoe_Put-in_Brochure.pdf

shows where "Bridge #1" and "Bridge #2" were, both of which were blown up when the GNAL nuke squad left in 1971. These are some of the coordinates we found earlier.

Ok, this is getting frustrating because you guys are faster at all this than I am! :-)

Dawson Forest Bridge
Posted August 29, 2012, by Anonymous

That's Luke posting, BTW.

Dawson Forest Bridge
Posted August 29, 2012, by Anonymous

That could also be the case. For example: http://bridgehunter.com/ia/jackson/bh53101/ (the image is from 1935 when the MILW was scrapping the line.) appears to be a very lightweight bridge (what you can see of it) when compared to a heavier gauge line like this bridge: http://bridgehunter.com/ia/scott/2930/ .

Dawson Forest Bridge
Posted August 29, 2012, by Andrew Pearce

We could be talking narrow gauge RR, or a very small diesel switch engine. Neither would need full scale RR strength.

Dawson Forest Bridge
Posted August 29, 2012, by Fmiser (fmiser [at] gmail [dot] com)

I agree, it doesn't look like a normal railroad bridge - but this was not a general freight railroad. It was a dedicated, remote controlled train that carried irradiated stuff from the reactor site to the laboratory. Not proof, but it wouldn't have to be as heavy as a general freight bridge would be.

Add to that, the brige in the photo is almost certainly build before 1950. And the deck is too wide. That's about when Lockheed made this area a nuclear research site. And obviously the area wasn't used for nuclear activities when the bridge was built (probably before 1920).

So - was it a automobile bridge already there? Was it moved there? Was the train light enough it ran across a pre-1920 automobile bridge?

Dawson Forest Bridge
Posted August 29, 2012, by Luke Harden (lmharden [at] iastate [dot] edu)

Perhaps, It doesn't seem to me like a railroad bridge either.

Dawson Forest Bridge
Posted August 29, 2012, by Robert Elder (robertelder1 [at] gmail [dot] com)

This looks extremely lightweight for a railroad bridge. I can't say for sure that it was not used by a RR but it looks very much like a ca. 1900 vehicular bridge to me. I am not familiar with this area at all, but could the RR have used another bridge in the immediate area?

Dawson Forest Bridge
Posted August 29, 2012, by Luke Harden (lmharden [at] iastate [dot] edu)

Yes, I'd added the blown-up girder bridge across the river, I just linked it as a related bridge and am waiting on permission from a Flickr user to us an image of the abutments.

Dawson Forest Bridge part 2
Posted August 29, 2012, by Andrew Pearce

You can see a sideview of the bridge at the :53 mark in the video at http://www.dawson.org/index.php?option=com_content&task=view&id=92 which confirms we're dealing with a 3 panel Pratt.

Apparently this is an old RR bridge, on the stubb end of North Gate Rd, a rail line that once supplied the Georgia Nuclear Aircraft Laboratory

depending on how you define the end of N Gate, the bridge could be at

34.368342,-84.165598

34.368316,-84.165586

34.376667,-84.187335

34.386371,-84.192656

34.360916,-84.179001

or several other spots where hiking trails or old logging roads give out just before the river.

and here is a hiking map for the area, which is the Atlantic Tract of the Dawson Forest WMA

http://www.georgiaoutdoors.com/hunting/WMAmaps/DawsonForestAtlantaTract.pdf

which shows Google's Clark Rd as Bagwell Rd, shows the tail end of North Gate as River Rd which neither Google nor Bing show ... etc. It almost seems like some darn secret government conspiracy. Oh wait, IT IS. Because this entire WMA property is where the super secret Lockheed Georgia Nuclear Aircraft Laboratory was back during the cold war!

http://www.gaepd.org/Files_PDF/gaenviron/radiation/radrpt2002_dfw.pdf

note the Hot Zone picture on page 2, which shows a RR crossing about here 34.356244,-84.146519

and then pull that up in Bing ... and Houston, we have abutments!

You're never going to see such a tiny truss skeleton with a satellite shot from either Google or Bing.

Dawson Forest Bridge part 1
Posted August 29, 2012, by Andrew Pearce (drew458 [at] barking-moonbat [dot] com)

Rail Road is Clark Road is blue trail/yellow trail,

Sweetwater is North Gate Road south of Rt 53,

Shoal Creek Rd is P7 road inside the park

here is a map that shows the bridge

http://etowah.secondsitellc.com/DawsonForestMap.php

here is the bridge and a description of how to get to it

http://anybodyseenmyfocus.blogspot.com/2011/12/dawson-forest-wildlife-management-area_04.html

Here is a close up; nothing is left but the truss itself http://etowah.secondsitellc.com/images/Dawson_Forest/DSCN3097.jpg

Had to cut this in parts cuz of server only letting me post 3 links

Dawson Forest Bridge
Posted August 29, 2012, by Luke Harden (lmharden [at] iastate [dot] edu)

On the subject of the railroad bridges associated with the nuclear facility, everything would have been marked on US government maps and probably on Lockheed documents, good luck sweet-talking them into letting you look at them. All the railroad tracks, ties, and bridges were removed (the bridges were blown up and, apparently, fragments can be found in the woods.).

Fun fact: The only building that remains standing is what was called the "Hot Cell," and it is still somewhat contaminated.

The railroad was controlled remotely and carried samples from the hot cell building to the reactor, where they were blasted by hard radiation as the reactor was raised out of its shielding. The railroad then brought the now highly radioactive samples back to the hot cell, where they were studied chemically and mechanically inside the cell with remote manipulators. The hot cell was too hot and far too radioactive for humans to enter, even when no samples were present, due to the heavy irradiation at the time.

They didn't demolish the hot cell building because it was thought that the dust raised by demolition would drift and cause further environmental contamination. It was left to sit until the isotopes present decayed to less harmful levels. It's fenced off so people won't go in and stir up dust.

Dawson Forest Bridge
Posted August 29, 2012, by Luke Harden (lmharden [at] iastate [dot] edu)

Whoopsie! I wasn't looking directly at the trail crossing and didn't pan far enough to to the right. Good job Don.

Dawson Forest Bridge
Posted August 29, 2012, by Fmiser (fmiser [at] gmail [dot] com)

Don, that sure looks like a truss brige to me!

From the map and your description, I gather the position is 34.36840,-84.16496. I'm changing the lat/long.

My map call the road north of the river North Gate Rd. The Blogspot photo Luke linked to, from the text, would have to be taken facing south. That too fits with what I see in the Bing image.

Good work, all!

Dawson Forest Bridge
Posted August 29, 2012, by Fmiser (fmiser [at] gmail [dot] com)

This page has a map of the nuclear site. There are two bridges listed on a line that my US Census TIGR map shows as Sweetwater Church road.

http://www.advrider.com/forums/showthread.php?t=405686

But only one is across the Etowah River at +34.356014, -84.140101 - though my map calls that Shoal Creek Rd.

The other - I think more probable - is at +34.381922, -84.152377. This is still on Sweetwater Church Rd. and the road looks much more overgrown on Googlearth.

There is another line that could be the railroad but isn't listed as such. If that line is the rail alignment, there would be two bridges on that one too. That line makes it's northern crossing at 34.364582, -84.148905 which is pretty close to the point Luke has for the railroad bridge.

Dawson Forest Bridge
Posted August 29, 2012, by Don Morrison

Oh, yeah. Those screenshots were courtesy of Microsoft Bing Maps and their imagery providers.

Dawson Forest Bridge
Posted August 29, 2012, by Don Morrison (bacchus [at] mchsi [dot] com)

Well, it wouldn't be the first time my brain added details that weren't there, but here's what I think I see.

On the map image, I connected with yellow dots Sweetwater Road and hwy 318, with a crossing at the location I cited in Bing Bird's Eye.

On the screenshot from Bing Bird's Eye, I have marked with red arrows where the old road approaches the bridge from north and south.

The blue arrow points to a portal member near it's upper hip joint. I can also see what looks like the bottom portion of a parallel portal member a short distance to the west of it, and possibly a vertical with a floor beam hanging down from the hip joint.

It looks like a top portal beam on the north a short distance below the red arrow. Possibly a vertical just northeast of the blue dot.

I wonder if Sweetwater Rd was renamed North Gate rd for the purposes of the wildlife area? I.e. Road from the north gate?

Uploaded file: JPEG image data, JFIF standard 1.01, 35637 bytes

Uploaded file: JPEG image data, JFIF standard 1.01, 394689 bytes

Dawson Forest Bridge
Posted August 29, 2012, by Luke Harden (lmharden [at] iastate [dot] edu)

I can't find it, it's supposed near the end of North Gate Road according to this: http://anybodyseenmyfocus.blogspot.com/2011/12/dawson-forest-wildlife-management-area_04.html

Dawson Forest Bridge
Posted August 29, 2012, by Luke Harden (lmharden [at] iastate [dot] edu)

There is nothing at that spot in Bird's Eye, Don. The coordinates I'd used were from the Flickr image, but that was too far from the river. I'm move the pin to each river crossing of the trail and open a Bird's Eye View of it and see if I can't find it.

Dawson Forest Bridge
Posted August 29, 2012, by Don Morrison (bacchus [at] mchsi [dot] com)

Enter 34.3684,-84.165 into Bing Bird's Eye view, then look for the truss. I can't see it in Bing Aerial view.

It really isn't visible on Google. Look near Blue Trail, just south of where Yellow Trail meets Blue Trail, at the river.

Possibly older Google imagery would show it, depending on daylight and season conditions.

Dawson Forest Bridge
Posted August 29, 2012, by Fmiser (fmiser [at] gmail [dot] com)

Luke, do you have specific lat/long data? Or did you just put in something that's in the area?