What if the valve broke while I was under way?
Would I be able to identify the flooding if it was submerged?
Would my pumps be able to handle the flooding?
Would I have the right tools and equipment to repair the damage?

I was surprised to learn that a 1-1/2 inch diameter hole 18 inches below the waterline admits 15 gallons per minute, allowing about an hour before the water floods the engine. A 6 inch diameter hole allows less than 10 minutes before the engine is flooded. That's not enough time to do much! What this told me was I better have a plan. Stopping a major leak or reducing it to a volume that the pumps could handle requires ingenuity, creativity, proper tools, and equipment. Just thinking of ways of fixing major leaks will give you a headstart when a leak occurs.

Explore your boat and Identify items such as the locations of all seacock valves, thru-hull fittings, propeller shaft, stuffing box, engine water pump, muffler, engine cooling system, transducer, etc. When the boat is heeling sinks, heads and rudder shaft, may also ship in large amounts of water. Examine the boat and identify items such as cushions, cabinetry, boat-hook, towels, life jackets that could be pressed into service as patches for the damaged hull and shoring to keep it in place. Learn how to reach areas of the hull obstructed by cabinetry and other accommodations. Have tools ready to cut or remove them. Know your boat from bow to stern.

Equipment needed for controlling a major leak includes soft wood plugs to close a broken seacock valve or hose, water activated epoxy and glass fabric or other type supplies that can be used to patch a ruptured hull or hose. Tools that should be accessible in an emergency are screwdrivers, hammer, hacksaw and blades, pliers, vice-grip, hand drill and bits, sharp knife, electrical and duct tape, long self-taping screws, nails, assorted hose clamps. Other items of use could be spare hoses, packing for stuffing box, caulking gun and 3M 5200 cartridges, inner tube rubber, face mask, fins and snorkel.

What follows are ideas that will give you a head start in preparing yourself for keeping your boat afloat.

Use marine grade seacocks that can be opened and closed with one 90 degree turn. Inspect and lubricate annually.

Keep a tapered softwood plug available at every below the waterline thru-hull. A good idea would be to use a lanyard and fasten the plug to the valve itself.

All hoses connected to thru-hull fittings below-the-waterline should be double clamped to the tailpiece. One clamp should go on the barbed portion of the tailpiece with the other hose clamp just below it on the pipe section.

All discharged lines such as toilet and engine exhaust should be fitted with a vent loop to prevent water from siphoning back into the boat.

Every boat should carry at least one electrical bilge pump and a couple of large-capacity manual pumps that can be operated from the cockpit.

In extreme emergencies you can use your engines raw water pump as a bilge pump. Close the raw water intake seacock, remove the hose, and place it in the bilge. Screening can be tied around the end to prevent it from clogging the engines water pump. A washdown pump can also be put into service in the same way.

For damage to the hull have an assortment of 1/8 inch pre-drilled plywood panels ranging in size from 3 to 12 inches square for use as temporary hull patches.

An area of the hull that is vulnerable to damage is the bow. In the case of severe hull damage a collision mat can be secured on the outside of the hull, using a small jib or tarp. The tarp should be at least four feet square and have grommets and lines attached ready for use. The lines should be long enough to encircle the boat (figure 1).

Major damage to the hull can also be controlled from the inside of the boat. If necessary remove any cabinetry to expose the damaged area, then plug the hole with a cushion, life jacket, towels or anything that will conform to the damaged area. Use a boot hook, oars or anything that can be used as a brace (Figure 2).

 Flooding usually results from failure of a thru-hull fitting, hose or valve, which will be difficult to identify if it is submerged. Take immediate action. Start pumping the bilge right away. Look for the source of the leak. Inspect all the below-waterline fittings. Examine hoses and clamps, and close any unused seacock valve. If your boat has been holed by rocks or collision concentrate on controlling flooding first. Once under control, construct a permanent patch. Radio for assistance.

 Hopefully this article has got you thinking of ways that you can keep your boat afloat. In most cases, flooding can be controlled if you are prepared and take immediate action.