There are several components that make up the anatomy of a mooring. Maintaining them is critical to reducing the risk of mooring failure, especially during a Hurricane.

Denis Owen, partner in Atlantic Mooring Maintenance, and a self-styled mooring specialist explains here how a successful mooring works. He says that placing a mooring is "not an exact science" and that he tends to "overbuild" to be sure his moorings are equal to the task.

Mooring components that need to be properly installed are:

1. The Heavy Weight - Sits on the ocean floor and hold the network of chains, buoys and ropes in place. When diagnosing a mooring Mr. Owen's company excavates around the weight but do not lift it up.

"The weight will settle into the sea bed and create suction which helps keep it in place. Lifting it will break that suction, it is also pretty hard to get that weight back in that exact same spot."

The weight must be heavy enough for the boat attached to it. It must also be a shape that does not allow for wrapping. "Any protruding parts will catch the ground chain and could cause mooring failure."

2. The Ground Chain - Usually a piece of 'ship's chain' that lies on the sea bed and acts as a shock absorber.

"Lighter weight would be pulled taught and subject to a jerking action from the waves. It is this jerking action that will cause the mooring to fail, not steady pressure, and the heavy ground chain cushions that action."

3. The Swivel - Allows the boat to rotate around the mooring over time without the chains twisting.

"During the year the wind will blow in every direction. If the chain twists it will pull the boat right over the top of the mooring and in extreme cases pull the bow of the boat into the water."

4. The Up Chain - A lighter weight chain (usually half to one inch depending in the size of the boat) that links the swivel to the buoy on the water surface.

5. The Buoy - Holds the weight of the Up Chain so that it doesn't have to hauled up to the boat, and marks the spot of the mooring. All moorings must be registered with the Department of Marine and Ports and should bear a sticker indicating registration.

6. The Bridle - Attaches to the boat to the Up Chain. It can be made of rope or chain and this depends on the size of the boat and the owner's preference.

Maintenance

Atlantic Mooring Maintenance provide a full diagnostic service which includes an examination of the above parts.

Some of the specific areas of concern are:

1. The connection to the Heavy Weight.

"We tend to use big shackles that can easily be examined even after the weight has settled into the sea bed."

The weight, barring an unusual event, is an almost permanent fixture.

2. Growth on the Ground Chain.

"If there is too much growth the chain won't be able to flex and provide proper shock absorption. With proper maintenance the ground chain should last 15 years or longer."

3. The condition of the Swivel. "Because the swivel can rotate it means it is a weak point for the mooring and should be replaced every two to three years."

4. The state of the Up Chain.

"In addition to electrolysis the Up Chain can get "thrash" which is an abrasion caused by wave action and movement in the water." Mr. Denis says that when a chain loses 20 percent of its girth it loses 70 percent of its strength. The Up Chain should be changed every two to three years as well.

5. The condition of the Bridles. "Bridles can wear down over time, the rope can become stiff in the sun." Chain bridles are subject to the same deterioration as the Up Chain.

6. The shackles that hold the mooring together.

"All shackles should also be examined, cleaned and rewired as necessary."

Mr. Owen explains that even with the life expectancies explained above every mooring should be examined annually by a mooring professional.

"The initial diagnosis is pretty involved and can cost some money but then after that we try to keep the costs down by staying on top of the maintenance."

He also says that DIY mooring maintainers can cause a lot of damage, particularly to other boats if theirs breaks free.

"Just like you pay someone else to invest your money, you pay someone else to look after your investment.

"Some people know what they are doing but a lot don't. For example a lot of people will hit the end of a shackle pin with a hammer to seal it. But this can also knock off the protective coating and cause it to rust."

That said Mr. Owen explains there are steps boat owners can take to protect their boat from an oncoming storm. His advice includes:

1. Putting chain to the boat if possible.

"It is stronger than rope and while you might have been diligent, the guy next to you might not have been. If his boat breaks free and lays on yours the extra strength of the chain may save your boat."

2. Make sure your bilge pump is working and your batteries are charged.

"Hurricanes can bring a lot of rain and we often see boats sink rather than break free of the mooring."

3. Make sure your bilge is clean so the water is easily pumped out.

4. Add extra safety lines from the mooring to other cleats on the boat in case your main bridles fail.

5. If possible touch base with the owners of the boats near yours to make sure everyone has properly prepared their moorings.

As with any Hurricane or storm preparation if you are unsure you should seek the advice of one of the Island's mooring professionals.