My guess is that it used to be a 15 foot straight pipe. wedged in the river bottom at lets say a 45 degree angle. The ship hit it in the direction that would further push it into the river bottom. This gouged the the ship tearing holes in it. But it also bent the pipe into its current u shape as the ship passed over. Since the pipe is now bent into a u shape it is not as likely to damage another ship passing by it.
http://www.wtop.com/index.php?nid=25&sid=356152
"Brentwood Facility to Irradiate Mail"
Updated: Wednesday, Dec. 8, 2004 - 2:55 PM
ARTICLE SNIPPET: "WASHINGTON (AP) - Any piece of mail sent to a federal agency in D.C. first has to go to New Jersey, where it's irradiated before returning south for delivery. But a new facility slated for Northeast Washington will do away with the trip to the Garden State."
What a coincidence that no ship has hit it before now. Is this possible?
You may be right, however, I'm having a hard time imagining the crew not hearing/feeling the "bump in the road". Also, the holes/tears were in the aft of the ship. Unless the aft was somewhat lower in the water than the fore, I would have thought the holes would be more forward, if your theory were correct. Any "old-salts" out there have any insight?
re: "15' pipe not an accident"
Let me try to put an end to this particular 'tin foil' discussion topic. While the PIQ (pipe in question) may or may not have contributed to the damage to the ship, it was almost certainly not placed there for that objective. I've spent a great deal of my life doing silly stuff underwater, and I tell you from experience that, for volumes of reasons, this simply CANNOT be the case; particularly where deployment by scuba divers as bad guys is concerned.
This is not to say that the ship damage was / was not an accident. Simply that the pipe was not placed for that purpose by malefactors.
Since the ship was penetrated by a gash while in motion, in my mind that almost assures that it was probably an accident. If you were going to take go after ships using that waterway, underwater obstacles would not be the drug of choice. My bet is the pilot erred and hit something he shouldn't have in an area in which he shouldn't have been, and is trying to cover.
sub6