Bidwell Bar suspension bridge

Carrying California SR 162 over the Middle Fork of the Feather River, now swollen into Lake Oroville here after construction of the Oroville Dam in the mid 1960s. It seems like kind of overkill for this secondary road! This bridge replaced an original suspension bridge, dating to 1855, whose site is now inundated under several hundred feet of water. The old bridge is now located elsewhere on Lake Oroville and is open to foot traffic.
I would guess that preserving this thoroughfare was part of the political agreement on building the dam, and _that_ probably accounts for such an expensive bridge.