I have been across this a number of times. The view to the downstream side is amazing. It blows my mind every time that I realize just how much water is behind this dam.
I have a thing for dams as well as bridges. this one is on my list to photograph at some point
first i was not sure about bridges over dams, but i figured with most of them being shut down due to increase in safety i would go ahead and add this.
2nd reason is because this bridge/dam had been place on the 'high risk' for failure designation, by the army corps. If the dam is to fail, it would cause severe flooding all they way into middle Tennessee. Just to give you a good idea this dam/bridge is the biggest reservoir of water east of the Mississippi. And Nashville has a emergency plan on hand just in case of the dam breaking.