Have a regime when the current’s abeam – ensure adequate manoeuvring space!

What happened?

The United States Coast Guard (USCG) has issued Safety Alert 03-19 relating to the consequences of manoeuvring in high current environments.

Recently there were three marine casualties that resulted in the sinking of towing vessels on the Lower Mississippi River.  One of the casualties resulted in a fatality.  These cases are all under investigation by the Coast Guard, but the preliminary fact finding indicates there are some similarities between the three incidents.

In all three cases ‘towing vessels became pinned against another object in an aspect that exposed the vessel broadside to very strong currents.’  Once in that position, the vessels could not recover and sank.

Whilst this alert deals with a river environment, the underlying issues are applicable to the marine environment, particularly where small boats are being used, and in the offshore renewables sector and/or where there are strong tidal flows.

The U.S. Coast Guard strongly recommends that towing vessel owners, operators, and other responsible parties take the following measures:

• Avoid transiting between two anchored vessels, between two barge fleets, or between any other set of stationary objects;
• Minimize the number of operations which require the vessel to be positioned beam-to the current;
• Establish a minimum distance between the towing vessel and another vessel/object prior to conducting any operation that requires the vessel to be positioned beam-to the current;
• Recognize the risks involved in operating under high current conditions and weigh those risks before attempting to cross in front of stationery objects or attempting an operation that requires the vessel to be positioned beam-to the current.

The full U.S. Coast Guard alert 03-19 can be found here.

Members may wish to refer to:

• Vessel made contact with rig legs [effects of wind and current were not properly risk assessed]
• Vessel hit moored barge whilst turning
• Near-miss incidents: Crew transfer vehicles approaching wind turbines