Vessel collision: Risks perceived as tolerable are not always what they seem

What happened?

A vessel was mooring in a river port, in a smaller basin area than originally planned.
A barge was moored alongside a terminal within the turning radius of the vessel.
The vessel’s port quarter grazed the starboard bow of the barge at 0.1 knots.
The vessel was not extensively damaged, but the estimated cost for repairing the barge was around USD350,000.
Why did it happen?
When the original plan changed, the pilot perceived the risk as tolerable.
Original plan was to turn in a larger basin further up the river. Vessel was required to turn in a smaller turning basin to save time and avoid traffic.
- Estimated turning area was 290m (950ft) across.
- Barge was 17m (55ft) wide and the vessel was 244m (800ft) long.
- This left a small margin of 29 metres.
Risk was not assessed or challenged by the bridge team.
- Complacency – the team performed this manoeuvre before successfully, so perceived it as safe to perform.
- Inadequate supervision – misjudgement of vessel movement, external forces (wind, current) and of the clearance to the barge.
What did they learn?

Avoid turning where there is only marginally enough room.
Ensure good communication between pilot and mooring teams, particularly on turning ranges to the shore/bank and other moored vessels.
Bridge team should be fully aware of vessel manoeuvring characteristics and inform the pilot accordingly.
Ask yourself or your crew

Have you ever been involved in an incident like this?
What is considered a ‘tolerable’ risk in mooring operations?
How does our vessel pilot communicate with the bridge teams? What can we do to improve communication?
How can you challenge workers that perform activities in an unsafe manner?

Published on 25/11/20 2148 Views

A vessel was turning in a river port. There was a barge moored alongside a terminal within the turning radius of the vessel and the vessel’s grazed the starboard bow of the barge.

Original material courtesy of IMCA