Mooring

A mooring is any permanent structure to which a seaborne vessel (such as a boat, ship, or amphibious aircraft) may be secured.

[1] The term likely stems from the Dutch verb meren (to moor), used in English since the end of the 15th century.

A swing mooring consists of a single anchor at the bottom of a waterway with a rode (a rope, cable, or chain) running to a float on the surface.

Ropes (particularly for marker buoys and messenger lines) should be "non floating" to reduce likelihood of a boat's propeller being fouled by one.

There are four basic types of permanent anchors used in moorings:[3] A vessel can be made fast to any variety of shore fixtures from trees and rocks to specially constructed areas such as piers and quays.

The main advantage is that during an event, such as a high wind or the close passing of another ship, stress can be spread across several lines.

However, should a highly stressed nylon line break, it may part catastrophically, causing snapback, which can fatally injure bystanders.

The effect of snapback is analogous to stretching a rubber band to its breaking point between your hands and then suffering a stinging blow from its suddenly flexing broken ends.

Quick release mooring hooks provide an alternative method of securing the rope to the quay: such a system "greatly reduces the need for port staff to handle heavy mooring ropes … means staff have to spend less time on exposed areas of the dock, and [reduces] the risk of back injuries from heavy lifting".

[9] The basic rode system is a line, cable, or chain several times longer than the depth of the water running from the anchor to the mooring buoy, the longer the rode is the shallower the angle of force on the anchor (it has more scope).

By adding weight to the bottom of the rode, such as the use of a length of heavy chain, the angle of force can be dropped further.

A buoy can be added along the lower portion of rode to hold it off the bottom and avoid this issue.

Non-line mooring ("hands-free") is used where pier time is highly valuable, and includes suction cups[10][11][12] or magnets.

Alternatively, simple moorings may be placed off the pier and vessels may tie to these instead of setting a temporary anchor.

The disadvantages of Mediterranean mooring are that it is more likely to result in collisions and that it is not practical in deep water or in regions with large tides.

A mooring used to secure a small boat (capable of being beached) at sea so that it is accessible at all tides.