Looking at historic aerials, this bridge was still in use in 1955, but by 1971 US 71 had clearly been rerouted and the old alignment abandoned. If the "new" bridge was built in 1969 I think it is safe to assume this bridge was bypassed and closed around this same time. The road bed had already been torn up in the 1971 aerial.
Ah, yes. I think this is the bridge I remember on US 71.
The current bridge was constructed in 1958. Thanks for the info on the old bridge. I have attached a family photo from 1943 featuring the old bridge.