D&RGW bridge ties and walkways?

I'm thinking of summer projects for my outdoor layout and was wondering about bridge ties and walkways on the D&RGW narrow gauge steel bridges.

I found this great photo by Rich Muth doing a search of the Chama River bridge on this forum:



It can be found in this discussion:

Chama River Bridge

I'm wondering if the walkway is from D&RGW days or if it was added at a later date?

I can't really find much info if any of the larger steel spans had walkways or not. And all of my D&RGW books are at my folks' place in Colorado while I'm living and working in California right now.

I model the late 1940s to early 1950s on our outdoor layout and was thinking of adding a walkway (and bridge ties) to the twin 6 foot bridges on the layout. So any info on walkways is appreciated.

Here are two photos of the bridges on the layout, along with a link to an extremely large version of the first photo:



Large Photo Link



Matt
Lake Forest, CA
Click Here for my model train photo website