Maritime Museum Emergency and Disaster Preparedness and Recovery Manual

Weigh the pros and cons carefully

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If you have to scuttle a vessel intentionally:
l Weigh the pros and cons carefully. In the right circumstancesa hurricane, for examplescuttling can be a viable means of saving a vessel from catastrophic damage. But the individual responsible for making the decision should be certain that the risks merit the consequences. A vessel without engine or electrical systems, in a good berth, could be more secure from storm damage while on the bottom than while afloat. However, each vessel is a special case, and it is worthwhile to outline in advance the circumstances under which such action might be taken.
l Consider the surrounding conditions. A large vessel that sinks in shallow water may lose stability and roll on its side, putting additional strain on the hull. A heavy accumulation of ice and/or snow, coupled with high winds, can cause a vessel to heel over and let water in through normally above‑water openings and poorly caulked planks. Swamping smaller vessels should get them out of the wind and seems a good plan for boats moored to anchors. However, swamping vessels moored to a dock requires careful planning for storm surges and wave action.
n Wind
It depends where you live, but most museum ships are likely to experience winds of fifty knots or more at least annually. Squalls, frontal passages, and winter storms routinely carry winds of this velocity, and your ship and moorings should be able to withstand them without extra measures. Strong moorings and a deck and rig kept shipshape are adequate preparation. Trouble may come from things like awnings, trash receptacles, gangways, or temporary rigging for maintenance. It is worth coming up with a plan to remove gangways and to rig temporary access from shore to ship, as large gangways can do tremendous damage to themselves, your ship, and the pier.
To avoid damage from wind:
l Have chafing gear in place. It is nearly impossible to rig chafing gear in a gale. Gusty winds, or gales of long duration, will get your vessel surging on her moorings as your shock absorbers (catenary in chain or synthetic line stretch) come into play. This is when chafe can have a serious impact, and any weaknesses in your mooring system will come to light as the vessel heaves against her lines. In a pinch, you might try some lard or vegetable shortening at chafe points; do not use petroleum products on fiber lines. If chafe is occurring, rig extra lines as backups. Ideally, your mooring system should have built‑in redundancy.

l Secure vessels for all directions. During a storm, winds can reverse themselves suddenly.
l Remove masts and rigging on smaller vessels. Get trailerable boats out of the water.
n Hurricanes
We habitually underestimate the damage potential of hurricanes. Because the strongest part of the storm is so localized, most of us will never experience the full force of a hurricane. However, there is a great danger in making inadequate preparations on the basis of this assumption. Here are some rules to live by:
l Hurricanes are unpredictable. They can change course and strength rapidly enough to leave you little time to revise your preparations. Act early, and prepare for the worst.
l Hurricanes are more powerful than most of us can imagine. A Category 1 storm has twice the wind force of a 50‑knot gale; a Category 3 storm has four times the wind force. Preparations should concentrate first on your vessel's survival, then on minimizing damage.
l Make your preparations and evacuate. Do not imagine that by staying with your ship you will help anything.
l Make your vessel as watertight as possible. Seal all openings with air conditioning duct tape. Tape windows from the inside. Use porthole covers if present. Remove all movable equipment such as canvas, dinghies, radios, tillers, booms, etc. Secure hatches tightly.
l Shut off fuel lines at tank, and close all through‑hull fittings.
Mariners tell of surviving hurricanes by moving their boats up tidal creeks as far as they could go and tying off to trees. If the water level rose, they would go still further. As the water receded, they would bring their boats back down in stages. These were desperate men trying to save their livelihoods. Such heroic actions are not expected today.
n Seas
Storm‑driven waves carry tremendous amounts of energy and are best avoided. If your berth is vulnerable, make plans either to evacuate the vessel or to minimize damage from waves. Pampanito, in San Francisco, has a very exposed berth, necessitating extensive mooring installations. Pampanito has been forced to make at least one dramatic escape.
If your berth is washed by relatively small waves, there are some effective energy‑absorbing breakwaters made of floating tires, often used by marinas.
n Tide/Storm Surge

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