There was, it looks like a wood trestle bridge there prior to the current metal truss bridge. The metal truss bridge might be older and was moved here, when a road elsewhere outgrew the capacity of the bridge.
Note in the 5th picture the pilings from the previous bridge deteriorating below the current bridge.
Generally speaking, depending on your state road budget, and the average daily traffic over a particular bridge, they are inspected every 2 to 3 years. A lot can happen to a wooden deck in that length of time.
Yes, it was scary driving over this bridge in a 2 ton pickup truck. If just painting it qualifies for upkeep - someone needs to examine the deck alot closer during the next inspection !
It appears that this bridge was actually (gasp) painted within the last decade. That indicates maintenance, which would allow for a load rating close to original design.