It seems like the bigger issue here is a complete lack of signs leading up to the bridge - If it's a contiguous road I can see how someone might be lulled into

It seems like the bigger issue here is a complete lack of signs leading up to the bridge - If it's a contiguous road I can see how someone might be lulled into a false sense of security. Ultimately, the final responsibility is the driver's, but there's very severe neglect on the part of the local government to allow the bridge to be unmarked and unsigned.