Step 1 - reroute surface traffic and develop a new Hazmat/OS/OD route. Step 2 - clear the river and get the docks open and going again Step 3 - rebuild the bridge, likely with precautions like dolphins (not the animal) before the bridge supports both in and outbound.
The blame game will happen concurrently to all of those I bet. Just thinking of it as a project to get through. I'm sure they have local salvage and diver crews - Roen won't be chugging out from Sturgeon Bay here...
