This is known as the Ohio Connecting Railroad Bridge or the Brunot Island Railroad Bridge.
I learned that this bridge is 70' above the water because somehow a woman drove her SUV onto the bridge and then fell to her death when the vehicle landed upside down in 20 feet of water. But her dog and cat survived. [post-gazette] I studied the satellite images and could not find a grade crossing of the rails in the vicinity. No wonder the police were "mystified."
|Street View, 416' back channel span|
|eBook, p 634|
|Left Half of p634|
|Right Half of p634|