Greetings David!
The 'tank is the old RT 50 bridge over the river, so its a pretty sound structure. The new bridge was built mostly because the old one (two lanes) couldn't handle the traffic. The old bridge was lower to the water, so there may have been a drawbridge in the center (one of the locals would know.)
Other states have picked up on using remnants of older bridges as fishing piers. There are at least two in southern NJ. Hopefully this will become a trend....
Unfortunately, with beachfront property at a premium, we'll have to wait and see if the old ocean piers are replaced. I understand one of the piers (can't remember which) was state-owned. Might be a good time for folks to start lobbying to get the pier replaced; There will be a lot of federal money flowing into VA and NC over the next few months....