How to Prepare Your Boat for a Storm

Courtesy of NOAA

Hurricane Sandy

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Hurricane experts are predicting that the next 20 years will be more active than the last. As sailors, there’s nothing we can do to change the outcome of these predictions. But we can be prepared. Planning for the safety of your boat and where it will survive best is a lot like the real estate business: location, location, location. And determining what steps you need to take should begin before a hurricane threatens. The first major decision, one that affects all subsequent action, is: Where will you keep your boat?

A secure marina may not be the most hospitable location during a hurricane. There are several important considerations. Does the dockmaster have an established hurricane plan in place? If not, will you be required to evacuate? The physical characteristics of the marina, its surroundings as well as the layout, construction and design of piers and slips all play an important role in the safety of your boat. And despite your best planning efforts, your neighbor may not have been so diligent in his. Loose boats in a marina wreak havoc.

If you plan to keep your boat in a marina, you’ll need to consider your boat and slip design as well as the harbormaster’s configuration. Many marinas designate that alternate slips be vacated when a storm approaches. Others require complete evacuation.

Assess the condition of the marina docks. Are cleats firmly attached? Are the pilings solid? Can the physical condition of the docks, piers, pilings and cleats withstand the tremendous forces involved in hurricane conditions? Several years ago, a vicious low-pressure system carrying storm force winds swept through Sausalito, California, completely severing several finger piers from the main dock. The entire assembly, complete with boats, was swept intact into San Francisco Bay.

If your boat is to remain at a dock, you’ll need to devise a docking plan radically different from your normal arrangement. For most boats, consider pointing the bow toward open water if possible. If not, try to point the bow toward the least protected direction. Unlike boats at anchor or on a mooring, a boat lashed down in a marina cannot turn to face oncoming wind and waves, which may come from totally opposite directions during the course of the storm, radically redirecting the forces on a vessel.

The key to your docking plan should be long lines -- the longer the better -- to accommodate the predicted storm surge. A good rule of thumb: Storm lines should be at least as long as the boat itself. The BOAT/U.S. Catastrophe Team estimated that as many as 50 percent of the thousands of boats damaged during Hurricane Andrew could have been saved by using better dock lines and docking arrangements.

Using longer lines will require using other boat owners’ pilings and cleats, and vice versa. Lines may have to be run across marina waterways to facing pilings or to anchors placed in channels. That requires extra planning with other boat owners and marina management. By the time you’ve completed docking your boat, it should resemble a spider in the center of a web.

Your efforts should prevent your boat from moving laterally and at the same time allow it to rise and fall during storm surge. Storm surge may raise your boat completely above adjacent pilings. If your boat isn’t held securely in place, it may be impaled when the surge recedes. Make sure the dock lines cannot slip off the tops of the pilings.

Severe storm surge may completely submerge docks, pilings and cleats. Floating docks present a different set of problems. Storm surge may lift them high enough to slip off their pilings and float away. Many marinas are protected by breakwaters or jetties. They may be totally submerged by storm surge, exposing your normally secure marina to increased fetch, open ocean surge and high waves.