If Your Boat Boat Must Stay in the Water
Make a dry run if you plan to move your boat prior to a hurricane. Take note of how long it takes and what problems you may encounter under emergency conditions. Are there bridges? Many communities require drawbridges to be locked down when a hurricane watch is issued.
Berth at a Dock
Choose a dock that has sturdy pilings and offers reasonable shelter from open water and storm surge.
Double up all mooring lines but provide enough slack so your boat can rise with the higher tides. Cover lines with chafe protectors at points where they're likely to wear. Put out extra fenders and fender boards - the more the better.
Anchor in a Hurricane Hole
Hurricane holes are deep, narrow coves or inlets surrounded by sturdy trees which block the wind and provide a tie-off for anchor lines.
The best location is far enough inland to avoid the most severe winds and tides, yet close enough to reach under short notice.
Anchor in a Protected Harbor
Historically, boats sustain less damage when they are at anchor. They can respond easily to wind and water changes without striking docks or other boats.
Heavy and extra anchors are needed to get a good hold, and enough line should be on hand to allow a scope of at least 10:1 for each anchor.
Mooring in Protected Harbors
Another alternative is sturdy mooring in a protected harbor. Boats can swing freely to face the wind and can't be slammed into a dock unless the anchor or mooring drags.
Consider what constitutes a sturdy mooring:
- Will it hold in a hurricane?
- How deep is the water?
- What type of bottom is it?
- What is the proximity of other boats?
During your practice run make a diagram of how your mooring / docking lines will be arranged. Note additional equipment that you'll need to secure to your boat.
Depth & Bottom Type
Normal depths may be altered radically during the approach or departure of a storm. Allow enough scope for surge.
Conversely, if depths are minimal, your boat may go aground if the wind blows the water out of the harbor. Are there rocks? Your boat may survive the storm only to be torn apart by rocks as the storm recedes.
Test the holding ground. Burying-type anchors in an ideal bottom may be impossible to retrieve after a storm. The best holding grounds are (roughly) in the following order:
- Hard Sand
- Soft Sand
- Soft Mud
Considerable testing in 1996 determined that fluke anchors had the most holding power in all types of bottoms. Fluke-type anchors such as Bruce, CQR, and Danforth bury themselves under load. Mushroom and dead-weight anchors drag with relatively little effort.
An effective arrangement is to use three burying-type storm anchors with chain rodes, deployed 120 degrees apart, and connected together using a heavy swivel. This mooring arrangement was one of the few that held during Hurricane Bob's onslaught.
Remember to increase scope 10:1 to allow for storm surge. Additional scope requires additional swinging room.