Upright and Watertight!

TABLE OF FLOODING RATES (Gallons Per Minute)

According to the National Institute for Occupational Safety and Health, between 2015 and 2019, there were 124 commercial fishing fatalities in the U.S.

Of these fatalities, 57% were due to the loss of the vessel itself, and the vast majority of those losses were due to the fact that the vessel lost its watertight integrity.

A well-designed and maintained vessel provides an excellent platform to protect you from a hostile environment, get you from here to there and to provide a means for making a living. Yet a vessel is only as good as its watertight envelope.    

Maintenance tip: conduct regular out-of-water critical inspections of the hull, through hull fittings, packing glands, cutless bearing, prop, shaft, zincs and paint. Inside the hull, inspect to see that through hull valves/seacocks open and close freely and fully.

Also: ensure that rubber hoses have two quality marine stainless steel hose clamps at each end. Replace older underwater rubber hoses with new hoses periodically. It’s cheap insurance and much easier to do when you are not knee deep in bilge water. Hang correct size wooden plugs from through hull fittings. The plugs will be easier to find if you have a problem. No closure valve on your through hull? That needs your attention.

If your vessel was built with watertight bulkheads, they’re probably not watertight anymore. Running wiring, pipes and other work that has never been properly sealed has negated the benefits of the original bulkheads and allow water to freely move from one compartment to another. Put bilge pumps and alarms in every watertight space. If the bilge alarm keeps going off and becomes a nuisance, don’t cut the wires to it to silence it—fix the problem.

While in the bilge, inspect for any PVC pipes or plastic fittings below the waterline. Plastic pipes are not made to withstand the pressure of someone’s foot which may be accidentally or on purpose used as a foot hold. Your bilge pump or pumps are not dewatering pumps. Bilge pumps are rated at gallons they can pump in an hour, while a dewatering pump is rated at gallons pumped per minute.

Refer to the associated chart and note that a two-inch hole located two feet below the waterline can let in 111 gallons per minute. A Coast Guard helicopter delivering you a dewatering pump will pump 120 gallons per minute—not quite enough. Don’t wait for a helicopter to deliver a pump to you; consider buying your own dewatering pump or electric sump pump if you have the room. And practice using or starting it during your monthly drills.

If you have an aluminum vessel, look for any dissimilar metals in the bilge. One fishermen almost lost his well-maintained aluminum vessel due to a mysteriously shaped hole in his bilge. When the vessel was hauled out and he inspected the shape of the hole, he remembered he had lost his stainless steel knife a few years ago on the boat. He didn’t recover the knife, but he found the hole the knife made through electrolysis.

With enough pumping capacity your patch or plug doesn’t have to be immediately perfect. Check the flooding chart again and you can see that a three-inch hole one foot below the waterline lets in 177 gallons/minute. If the hole is reduced to one inch, you could keep up with the flooding with a five-gallon bucket—and a lot of effort.

And make a flooding control kit with that five-gallon bucket while you’re at it. Fill it with soft wood wedges and cones that will swell in a hole. Include a headlamp for visibility and a portable VHF radio to talk to the wheelhouse. A 5/16″ nut driver works fast on hose clamps. A hatchet can enable you to split wedges so they fit in a split seam or pipe. Cotton rags around the wedges and seams will swell and make it more watertight.

Also, a hacksaw can cut wedges flush so they can be taped around a pipe. You’ll want a wooden mallet for driving plugs. Bicycle inner tubes stretched over a leaking rubber hose will make a quick temporary fix of a leak. Also include grease tape, twine, oakum, duct tape, wire ties, pipe wrenches, backing material like rubber, old survival suit neoprene, a knife and waterproof epoxy.

Keep shoring material like two-by-fours handy to use to keep plugs or patches in place. A large tarp can be used in some cases and “foddered” under the vessel. The water pressure can keep the tarp snug over the hole. Don’t let the hole continue leaking while you’re looking for the perfect fit. Stuff it with something to slow the leak.

More tips: call the Coast Guard early and keep in contact. Be sure to de-energize electrical sources in a flooded space. Maintain situational awareness in a flooding emergency and give yourself an exit and time to escape in case of sinking or capsizing. Train your crew on what to do in a flooding emergency.

Prepare and drill your crew and you’ll live to fish another day.