English Maritime Terminology on Ship and Cargo Handling

Securing a Merchant Vessel: Anchoring, Mooring, and Berthing

When a merchant vessel is not underway, it needs a safe and secure place to rest. There are several methods for achieving this, each suited to different situations and purposes.

This chapter looks at the various ways merchant vessels can be stationed: anchoring, mooring, and berthing.

At Anchor:

• A vessel is considered anchored when it uses a heavy weight, called an anchor, attached to a long chain or cable, to secure its position on the seabed.
• Anchoring is typically a temporary measure, used for waiting, short stays, or in emergencies.
• Anchoring locations are designated as anchorages and are chosen for their depth, seabed composition (to ensure the anchor holds), and protection from wind, waves, and currents. Anchorages are also situated away from busy shipping lanes. 

Moored:

• Mooring involves securing a vessel to a fixed object on the water's surface, often a permanent mooring buoy.
• Mooring buoys are anchored themselves and have lines or chains with attachments for the vessel to connect to.
• Mooring is used for both temporary and extended stays, depending on the situation.
• Common locations for mooring include designated mooring areas within ports or harbors, or alongside offshore facilities.

Berthed/Docked:

• Berthing, also sometimes referred to as docking, describes a merchant vessel secured alongside a pier, quay, wharf, or jetty within a port or harbor.
• These structures provide a solid, stable surface for the vessel to tie up to using mooring lines.
• Berthing is primarily used for loading and unloading cargo or passengers, and for extended stays while in port.
• The specific terms "berthing" and "docking" can have slightly different meanings depending on region or context, but for merchant vessels, they generally refer to the same action.

Additional Mooring and Berthing Maneuvering:

Within a commercial port, maneuvering a merchant vessel into position for mooring or berthing requires precise planning and skilled seamanship.

Common additional terms used in this process include :

• Alongside: Describes the position of a berthed vessel, which is lying parallel to the pier, quay, wharf, or jetty.
• Aground: This is a dangerous situation where the vessel runs onto the seabed or shore, potentially causing damage.
• Spring lines: These are mooring lines positioned diagonally from the vessel's fore and aft sections, helping to hold it in position against wind and current forces.
• Breast lines: These are mooring lines running perpendicular to the vessel's side, securing it against movement away from the dock.
• Headlines and Sternlines: These are mooring lines attached to the bow (head) and stern of the vessel, respectively, to prevent fore and aft movement.
• Line handlers: These are crew members specifically responsible for handling and securing mooring lines during berthing and unberthing operations.
• Tugboats: Powerful harbor vessels often used to assist merchant ships with maneuvering into tight spaces or during challenging weather conditions, especially when berthing or unberthing.