The previous map for this bridge pointed at a closed concrete arch, which I have now added to the website.
This Whipple Bowstring is on a nearby drive. It is not privately owned as sometimes referenced, but instead is part of the Albany State Police K-9 Training Center. Despite some intimidating signage about authorized vehicles and such, it appears pedestrians are allowed on the bridge according to another sign. I was able to walk on the bridge without being disturbed.