Looks like we have some options
COSM groupie Leighton has come up with a plan using some structures some COSM members have built in the past.
Another plan for expansion includes some industry excuse the roughness of these two. Very preliminary designs
Dual gauge trackage. A true Colorado railroad
Engineer-Joe posted:Thanks for sharing, again!
Bridges add excitement to model RRs for me. They are as important as any other piece of equipment on the layout, at least.
This bridge, is amazing.
Joe it is an incredible model. 
Meeting of the minds and some coffee
Original concept drawing for reference
Progress update 11/16
Preliminary contour study
Mock up with 75" radius S turn
Acquired brass through plate girder 15.75"
This will be a fabulous project.
you're not kidding!
Lookin great!
I love the idea of the 3 styles of bridges together.
I love the combination of vision, modelling skill, and art that Eric shares on the forum. His and the posts of other active modelers make checking out the 2 rail forum an enjoyable part of my day.
He also encourages us to be more creative with our own layout photos.
I couldn't wait; I set up a test shot of the two bridges together. Cool huh!
Thank you gentleman
Some interesting images
As a bridge troll, I can tell you just when you think you've seen it all with respect to bridges, you come across something you thought you'd never see. There was an old Pacific Electric steel truss bridge in San Bernardino across the Santa Ana River that started out as a wooden trestle. On the south side of the bridge, the trestle pilings were all in place leading up to the concrete footings for the steel bridge. Best guess is that the bridge got washed out in one of the floods that hit that river (one in 1938 took out the trestle on the ATSF Redlands Loop). Somewhere I have photos I took a couple of years before they took down the bridge to make an access road (a less attractive concrete highway bridge). I've even seen bridges built from decommissioned 89-foot flat cars. Go figure.
Cool it is, Erik. 
those are some serious model bridges Erik.
I like that bottom string truss in your photos.
Bridges are a marvelous example of function leading form.......and producing something of rugged beauty and symmetry.
Off we go with the build of the sections for installation. With some raw materials together I produced a final conceptual drawing of the project. Used as a dual purpose, diorama, portable layout, and home layout installation in the future.
I have built a couple of plastrut bridges adding rivet detail but nothing close to this bridge. Again, WOW!
Erik, it looks like John is deep in thought thinking this scene would look so much better with about 4 or 5 Lionel girder bridges in a row. So to help you guys out I would be willing to send you a 1/2 dozen of those and since you won't be using the 2 bridges pictured I think I might find a home for them. Seriously that scene really is looking super. Don't forget Scale City Designs has bridge shoes avail if you need them for the girder bridge if you don't want to take me up on the more than fair trade I offered.
I do need some bridge feet where do I send the money ?
Glad you are finding some enjoyment in this project.
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