This is a great shot of the bridge. I was looking closely at the detail in it (the resolution on some of these early black & white photos is amazing) and noticed quite a few things. Click on the picture to open it up and then zoom in. Here’s what I noticed:
First, it looks like it was taken from the old visitor lookout on the Page side of the canyon. Do you remember that spot? It’s still there but blocked off. It provided a great view of the dam and bridge from just downstream of it. There was a parking lot and a short trail down to the lookout. You can still see it on Google Earth. Back to the picture. This is looking upstream. Notice that on top of the bridge, construction is still going on while visitors are allowed to be there. I don’t think anyone would get away with that today. You can see the footbridge in the background. This also provides a good shot of the dirt coffer dam that was built to divert water (via the diversion tunnels) around the dam site during that early construction. Notice too, the first few levels of the dam that have been poured. The penstocks are visible, angling out of the top of each level. Look how small the people are standing on the dam. Notice too, the wooden walkways and stairs between each section. Those were constantly being moved as the dam went up. I remember standing on the bridge so many times, watching these same things going on below.
Did you notice the ladders at the top of the bridge? Do you see the cables tied to the handrails by the ladders? Follow them down to the horizontal cross brace and you’ll see two workers (one on each end of the brace) working to secure the cross brace to the main structure. You can see the cable from the crane on top between the two workers at the top. It looks like the crane is holding that cross brace in place while it’s being attached. You’ll notice the cross braces on the other side of the bridge are already in place, but the one to the left of the one they’re installing is yet to be added.