Thursday, May 6, 2010

Lessons Learned—Collision, Fire in Tampa Bay—Part I

Excerpt from U.S. Coast Guard “Proceedings of the Marine Safety & Security Council” magazine by Ms. Barbara Chiarizia, executive editor.


Lessons learned from marine casualty reports are regularly featured in Proceedings of the Marine Safety & Security Council magazine. These articles explore marine incidents and the causal factors, outline the subsequent casualty investigations, and describe the lessons learned as a result.

It is important to note that lives were lost in some of the marine casualties we present. Out of respect for the deceased, their families, and surviving crewmembers, we do not mention the name of any person involved.


August 10, 1993 dawned clear and warm in Tampa, Fla. Visibility was good, sea conditions normal. So why did three vessels—piloted by seasoned mariners—meet in collisions that caused a catastrophic oil spill and fire?

The vessels in question, the M/V Balsa 37, a 4,337-gross-ton freighter; the integrated tug barge Seafarer; and the tug Capt. Fred Bouchard were transiting Tampa Bay.

The Balsa 37 was outbound, carrying 6,000 metric tons of phosphate. The other vessels were inbound. Seafarer was made up to the tank barge Ocean 255, which was carrying 236,000 barrels of petroleum products. The Bouchard was pushing the petroleum-laden barge B. No. 155.

Egmont Channel and Mullet Key Channel
Just before dawn the vessels approached the confluence of Egmont Channel and Mullet Key Channel. The Bouchard had suffered a starboard engine casualty and was only making six knots.

The other inbound tow was approximately one-half mile astern in Egmont Channel as they both approached the turn into Mullet Key Channel. The outbound vessel was at that time transiting Mullet Key Channel.

The USCG Marine Board of Investigation report noted that all conferred regarding meeting arrangements. It is reported that the pilot of the lead inbound tow radioed to the outbound vessel, proposing a port-to-port meeting. This request was echoed by the captain of the trailing inbound tow. It was agreed that all would pass port to port.

Faulty Assumptions
There were many factors that led to the subsequent marine casualty. The various mariners made assumptions regarding the intentions of the other vessels.

For example, the pilot of the outbound vessel assumed that he would meet the Bouchard first, as it was the lead inbound vessel when the meeting arrangements were made. Those aboard the inbound tows assumed that the outbound freighter would steer a course that would keep it well to the north side of the waterway at the turn into Egmont Channel.

Neither of these (or several other) assumptions was correct, and the outbound freighter collided with the inbound Seafarer tow near mid-channel, as that vessel was overtaking the slower inbound Bouchard. The outbound vessel then collided with the Bouchard tow.

The results were catastrophic. More than 5,000 barrels of oil spilled from the B. No. 155, and Ocean 255’s no. 1 starboard tank ruptured, its cargo set alight by the sparks from the collision. Subsequently, the Ocean 255’s no. 6 starboard tank, which was loaded with more than 16,000 barrels of jet fuel, exploded.

This incident closed the main ship channel for the Port of Tampa and caused significant environmental damage. The U.S. Coast Guard convened a Marine Board of Investigation to determine how this occurred.

To better understand the interactions that led to this calamity, in Part II we will review the voyage of each vessel.


For more information:
Full article is available at www.uscg.mil/proceedings. Click on “archives” and then “2007-08 Vol. 64, Number 4” (Winter 2007-08).

Subscribe online at http://www.uscg.mil/proceedings/subscribe.asp.

Direct requests for print copies of this edition to: HQS-DG-NMCProceedings@uscg.mil.

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