What to Do When Your Boat Is Taking On Water: Emergency Steps and Prevention

As soon as you notice water rising, have everyone put on a life jacket and fasten it. Put children and non-swimmers in theirs first. Bring the handheld VHF, phone, flares and a flashlight up on deck.

If the water is gaining or you're not sure you can stop it, call before it gets worse. The USCG's MAYDAY format on VHF channel 16:

1. "MAYDAY, MAYDAY, MAYDAY"
2. "This is [boat name, three times], [registration or call sign]"
3. "MAYDAY [boat name]"
4. Your position (GPS latitude/longitude, or bearing and distance from a landmark)
5. The problem ("taking on water, sinking")
6. Number of people aboard, life jackets on, boat length, type and hull color Then release the mic and listen. Repeat if no answer. A DSC radio connected to GPS can send an automatic distress alert with your position by holding the red distress button; follow it with the voice call on 16. If the situation is serious but not yet life-threatening, call "PAN-PAN" instead, or call your tow service (Sea Tow or TowBoatUS). Near shore, 911 on a phone also works. If no one answers, activate your EPIRB or PLB.

If you're underway, slow down and stop unless you need to run for shallow water (step 9). Speed can force water in through a damaged hull, and the bow wave often hides where it's coming from. Lift hatches and floorboards and look with a flashlight.

Follow the water uphill to where it's coming from. In salt water, a fingertip taste helps: salty means the sea is coming in; fresh water may be the boat's water tank or a burst freshwater line (shut off the freshwater pump). Check in this order, fastest first:

• Drain plug (trailer boats): is it in and tight?
• Raw-water strainer lid, engine cooling hoses and the raw-water pump
• Through-hulls and hoses: head, sinks, livewell, washdown, cockpit drains, transducers
• Shaft stuffing box or dripless seal, rudder post
• Sterndrive bellows or outboard transom fittings
• Exhaust hose and muffler (a melted exhaust hose after overheating can let water in)
• Hull damage after hitting something

If the leak is from a hose or fitting with a seacock, close that seacock. If you can't tell which one, close every seacock you can reach except the engine intake if you need the engine to get to safety (and the cockpit drains). On engines that run with cooling water, an overheated engine is better than a sunk boat.

Make sure the electric bilge pumps are on (switch them to manual), and that their intakes aren't clogged with debris. Start the manual pump and put someone on buckets. Keep the batteries charged by running the engine if it's safe to do so.

• Broken through-hull or hose with no seacock: push a tapered softwood plug firmly into the opening and tap it in. Wood swells as it gets wet and seals better over time. Tie it in place if you can.
• Split hose: wrap rescue tape tightly, or cut off the bad end and re-clamp if there's slack.
• Loose hose: push it back on and tighten or add a spare clamp.
• Crack or hole in the hull: stuff rags, cushions or a life jacket into it from inside and brace them with a boathook, floorboard or anything solid. A sheet of plastic or a sail pulled over the outside of the hole with lines lets water pressure hold it against the hull. Underwater epoxy putty can seal small leaks once the flow is slowed.
• Stuffing box gushing: stop the shaft (shut down the engine) and tighten the packing nut a little if you know how.

Shift weight to raise the leaking side or end, if that brings the damage above the waterline. Keep monitoring the water level: mark it on something and watch whether it's rising, steady or falling. Update the Coast Guard or your tow service if things change.

If the water keeps gaining and help is far away, head for the nearest safe shallow water, sandbar or beach while the engine still runs. A boat sitting on the bottom in shallow water is far easier to save, and people can stand up. Avoid rocks and surf if there's a choice. Tell the Coast Guard where you're going.

Stay together, life jackets on, and stay with the boat as long as it floats: most boats float awash, and rescuers look for the boat. Take the handheld VHF, phone, EPIRB or PLB and signals. Only leave if the boat is on fire or about to drag you under.

Once you're safe and towed or beached, have the boat hauled and the cause found and fixed before it goes back in. If it sank or the engine got wet, call your insurance company first, and get the engine "pickled" by a pro quickly. BoatUS notes that a hit you hardly noticed can cause a sinking hours or days later, so after any hard grounding or strike, do a short haul and check below the waterline.

Most sinkings in the BoatUS files were preventable. Check:

• Every below-waterline hose, clamp, through-hull and seacock (see the seacocks guide). BoatUS suggests replacing hoses that are 10 years old or more.
• Stuffing box or dripless seal drip rate; repack rather than just tightening.
• Sterndrive bellows: inspect yearly and replace at least every five years (BoatUS).
• Raw-water impeller: an impeller failure leads to overheating, which can melt the exhaust hose and let water in.
• Cockpit drains, scuppers and their hoses: run a garden hose into them and watch where the water goes.
• Transducers and sensors with no seacock: look for dampness around them.
• Drain plug: keep it on your key ring or tie it to the transom strap so it can't be forgotten.
• Bilge pumps, float switches and a high-water alarm; a pump cycle counter shows a slow leak early.
• A softwood plug tied near each through-hull, and a crew briefing on where they are.