Underbuoy Single Point Mooring risks

Risks to Single Point Moorings

Hazards and risks to Single Point Mooring Terminals
such as Catenary Anchor Leg Mooring (CALM) buoys


A Single Point Mooring Terminal is exposed to the variables of the marine environment and the changing circumstances of operational procedures.

Typical hazards and risks to Single Point Mooring (SPM) terminals

  • Tanker or random vessel collision with the SPM
  • Tsunami or other exceptional surface wave event
  • Hurricane or other exceptional wind behaviour
  • Soliton or other submarine wave event

Below are two instances of vessel collision with SPMs

SPM CALM Buoy damage

SPM vessel collision damage

Reducing risk to Single Point Moorings

Potential consequences of an event to an unprotected SPM

  • Major offshore oil spill
  • Environmental pollution
  • Expensive oil spill clean-up
  • Injury to personnel
  • Damage to assets and cost of repair
  • Terminal downtime and demurrage cost
  • Negative media attention
  • Higher insurance premiums
  • Compromised terminal integrity
  • Damaged reputation

Consequences of vessel collision with Single Point Moorings

A vessel collision could drag the Single Buoy Mooring beyond its working envelop; resulting in the rupture of the underbuoy hoses and uncontrolled spillage.
Single Point Mooring Vessel Collision hose rupture
The PLEM (Pipeline End Manifold) is fractured by the Single Buoy Mooring being dragged beyond its working envelop. Leakage at the seabed is difficult to control. The cost of downtime, repair and clean-up could be considerable.
Single Point Mooring Vessel Collision PLEM fracture
Reducing risk to Single Point Moorings

Damage to the submarine pipeline at the seabed could be in more than one location. Downtime, leakage and the cost of repair could be extensive.
CALM Buoy Vessel Collision pipeline damage