What is the maximum load a mooring bollard can take?

What is the maximum load a mooring bollard can take?

Report Text:

Whilst at Nassau I took this photo of another vessel where five of the ship’s aft mooring lines were secured to one bollard. I do not know the breaking strain of the mooring ropes or that of the bollard, but I suspect that the combined strength of the ropes may have exceeded that of the bollard. However, I do not recall reading of any incident in which a shore bollard has been pulled from the ground.

CHIRP recalls an incident on March 5, 2009, MSC Fantasia drifted away from the dock side in Palma de Mallorca Spain. High winds up to 110 km/hour created excessive loads, these caused the shore mooring bollards to be pulled out of the concrete deck and not the ship’s mooring lines parting. The bow then drifted away from the dockside causing a passenger gangway to collapse into the water. One passenger and three crew members had to be rescued from the sea. The passenger was taken to hospital with head injuries, three crew members were treated for hypothermia.
CHIRP also read the Nautical Institute MARS Report 200539 Failure of Shore Bollards. This incident occurred while on a seldom used berth, with strong gusting winds, the berth only really had one bollard for headlines, one for breast lines and one for springs. The breast line bollard failed and due to a lack of spread of lines the ship drifted off of the dock. The Port Authority had built a mooring dolphin especially for cruise ships and provided assurances that it was strong enough for all of the headlines – it wasn’t and the entire dolphin collapsed, taking all lines with it.

CHIRP Comment

It is the terminal operator that is contractually responsible for providing a safe berth. Mooring bollards should have a determined SWL rather than having to rely on assurances that they are strong enough. It is not possible for a Ship’s Master to verify the capability of each mooring bollard. The Master should also be aware; the ship’s own mooring layout capability will impact the loads on the bollard.
Ship owners should check with their agents to verify the moorings bollards on the assigned berth are adequate for the size of ship nominated to the port. Best practice can be found in the LNG shipping industry where computer programmes are used to verify mooring capabilities of a berth before a ship visit.