Flooding

Water in the Boat – Prevention

Administrator — Tue, 20 Jun 2017 19:09:57 +0000

Water in the Boat – Prevention

Dick York

Administrator Tue, 06/20/2017 - 19:09

You have been reaching along fast and you step below after a great watch on deck, and splash, your foot goes up to the ankle in water in your boat. Oops, no one wants this scenario. Like many other emergencies, water in the boat can be minimized by proper preparation and good habits.

Other articles in our web pages deal with flooding and its consequences. This one focuses on Prevention … minimizing the chance that water comes in the boat in the first place,

Some preparation you can apply to minimize water in the boat.

Check all those holes in the hull of your boat. Through-hulls and attached hoses are holes through your hull. You also may have several holes at the waterline, without seacocks on them. You also have stuffing boxes for shafts and rudder posts.
Protect against pumping water into your boat and don’t leak dynamically.
Avoid deck leaks, anchor well and locker leaks.
Don’t hit anything hard: stand a good watch and keep adequate sea-room.

All Those Holes in the Bottom of Your Boat

You have many holes in the bottom of your boat (look when hauled out some time).

Under-water through-hulls for inlets for your engine(s), inlets and outlets for your heads, inlets for refrigeration and air conditioning, sink drains, inlets for wash-down pumps, etc., all of which should have seacocks.

Outlets at the waterline for exhausts, deck drains, bilge pumps, outlets for refrigeration and A/C, and your propane locker drain. Many of these live just above the waterline … when you are not underway and not heeled over. These may not have seacocks.

Cockpit drains will not have seacocks, and may be underwater or at the static waterline.

Stuffing boxes or shaft seals for your propeller shaft and rudder.

The point is, of course, each of these is a potential opening through which the ocean can flood your boat. One source(*) reports that a two-inch hole one foot below the water allows 78 gallons per minute, increasing to 136 gallons per minute if that hole is three feet below the water. Your standard pump rated on paper at 1100 or 2000 gallon per hour will not be up to the task.

So avoid the sea coming in at all. Here are some ways to minimize that risk.

So avoid the sea coming in at all. Here are some ways to minimize that risk.

Close unused through-hulls. On passage you may want to close through-hulls that you will not use underway. When we are away from the boat for a week, all our through-hulls are shut (except for the main engine intake).

Make sure the head is left with the pump not able to leak. I once was at a dinner party on a boat when suddenly water was flowing out of the head compartment. A novice had left the pump handle up and the lever on “flush”, and there was just enough wear in the system that water started to leak into the bowl. Soon it was over the rim of the bowl (below the waterline!), and into the head area. Know how to isolate the head intake (normally lever to “dry” and pump handle all the way down). Instruct everyone to leave it that way when you train people on the use of your heads.

Check lee side sinks and heads when heeled over. The fixtures may have been above the waterline at rest, but now they may be underwater and flooding. Do this regularly: a check valve in one of my head sink drains acts up, so when heeled over on starboard tack that sink can be under the waterline and leaking into the boat. On some boats when underway you will want or need to close some drains unless you are actually using them.

Make sure your hoses do not leak, and they stay on the end of the through-hull or seacock. Feel the hoses from each through-hull; they should feel like a new hose, not mushy, crackly or with sharp points coming out. Look at each hose, as much as possible, for cracks or dried up sections; you may see these, especially at bends and at each end. Check the hose clamps on the ends. There should be two at each end, and they should not appear corroded at all. Try to screw them a bit, and see if they break. Replace any you do not trust.

Remember there are two ends to every hose. Any hose that could be below the waterline at either end, while heeled or at speed, needs to have two clamps. (Or, you can just put two on every hose end aboard, and be simple and safe.)

Check your through-hulls that they are not about to break or pull off the hull. If they are “plastic”, wiggle them and work the seacock. Yes, you can lubricate plastic seacocks, and it is worthwhile. If your seacocks are metal, you not only have to lubricate them, but make sure the bonding system is working. There are many approaches to bonding underwater metal (see e.g. Nigel Calder’s Boatowner’s Mechanical and Electrical Manual, or other similar manuals), but whatever method you use, please follow it exactly. Make sure all bonding wires are in place and not corroded away. One of the boats with whom we were going to buddy-boat across the Atlantic noticed they had a leaky through-hull two days before departure. After a wiggle, it almost fell out of the hull, eaten away from galvanic action. If they had not found it until after departing for sea…???

Check how you stow goods and spares near through-hulls. Are you putting a container of heavy spares near a through-hull that will break off if it is hit by the box? Is that box tied down properly? What about your anchor and chain while racing? Will it take out a head sink drain hose? Remember, on a boat, everything can and will shift.

While you are there (and this is more preparation than prevention), make sure you have a soft wooden plug of the right size tied near every hole in your hull. I also keep a few extra plugs in a high spot that I could reach in flooding.

Again, in preparation, make sure everyone in your crew knows the location of every hole in your boat. A simple boat plan that all crew have reviewed is an effective way to execute this training. Some skippers actually label any locker doors, floorboards, etc. which have a through-hull behind them.

On your launch date, check for water in the boat immediately. Look around for weeping and leaks. Check whatever kind of shaft seal or stuffing box you have for your engine and rudder then too. Make sure you have maintained the proper lubrication for these devices, if any is called for.

Check again when you are underway at a good speed. The rudder is now farther underwater, and the seal may leak at speed but not at rest. I have three outlets in my transom (engine exhaust, genset exhaust, and one cockpit drain) which are above the water at rest, but which are several inches underwater when sailing or powering fast. Check for leaks at both speeds.

If your shaft seal goes, how will you stop the water? (Sometimes a towel works, backed up by some hose clamps, if the engine is not running.)

On some boats, the angles are right such that a loose bolt on the propeller shaft will let said shaft slip right out of the bottom of the boat, without stopping. Three things to do for this: first, have your mechanic check the bolts that hold the shaft, and have them aircraft wired to not back out; second, think about stopping the shaft from falling out – in some cases people can couple a spare zinc or a hose clamp on the shaft inside the hull to stop a total loss; and third, carry the right size soft wooden plug nearby, as the size of this hole can be big and the water will flow in fast.

Check your rudder and shaft on the hard each year to assess whether or not you have a risk of dropping the rudder at sea. It happens!

Protect Against Pumping Water into Your Boat, and Don’t Leak Dynamically

Most boat have pumps, engine cooling, refrigeration, which can force water into your boat if the output is compromised. Also, seemingly innocent plumbing can become a leak when the boat is underway, especially when sailing fast or heeled.

Make sure all hoses on your engine and generator (if any) are fresh and well connected. Old hoses provide a way for your engine to pump sea water into the boat if there is any breech, and you are likely not to notice this at rest or under sail. Closely check the exhaust area, as many problems develop there.

Make sure all siphon breakers on outlet hoses are working, so you do not back-siphon your engine exhaust or head outlets. The breather is at the top of the big, inverted “U” that is above the waterline on these devices. On the engine breather, it is said one can suck on the siphon-breaker to see if it is operational. Sucking is not recommended for siphon-breakers on head outlet loops.

Make sure the electrical breaker for a salt-water wash-down pump is turned off after the washdown. If not, any breach in the hose beyond the pump, toward the spigot, will mean the wash down pump will pump water into the boat at about 40 psi! Check other systems that may “automatically” turn on and pump salt water, as they have the same issue. I have one friend who has pressure salt water to the galley for washing up during long passages. One item of crew training on that boat is: the pump breaker must be off after galley cleanup.

Many “waterline” through-hulls are underwater at some point of sail. Another friend had a bilge pump that exited above the waterline on the port side, about amidships. Hard on the wind on starboard tack, the outlet was under the water, and the hose had insufficient loop in it. The water would siphon back in the hose, move to the bilge where it had to be pumped out all over again. If someone accidentally had turned off the automatic bilge pump switch, the sea would just fill the bilge and then the boat. Of course, there was no seacock on a “waterline” level outlet.

Consider putting seacocks on all outlets at the waterline (but not on cockpit drains). I did this before going around the world, as any hose leak could quickly be shut off by anyone in the crew, and we could find and deal with the bad hose later. Of course you must not close a bilge pump outlet unless you know that is the source of a leak and you have turned the pump off.

Deck Leaks, Anchor Well and Locker Leaks

Gaps in your deck structure above the waterline may only allow water in when you are in heavier seas or beating. But the danger is high as these openings tend to be so large (measured in square feet) they can fill the boat quickly.

Does your anchor well drain into your bilge, or are there other openings from your anchor well to the interior of your boat? If so, make sure the door on the anchor well is in good shape, especially the hinges and latch, and any weather-stripping around the opening. If you are in heavy seas, the door could rip off, fill with water and then drain into the boat. Or a moderate leak could get significant water into the boat before you are aware.

Similarly, check all cockpit locker doors and lazarette hatches and make sure the hardware and seals are secure. This is a bit different than the anchor locker, as a slow leak or a loose door will drain directly into the boat. You are more likely to know about this kind of leak, but the consequences can be more severe, as they provide a larger opening.

You should think through how to plug a hole from a lost hatch (e.g. the foredeck hatch rips off the hinges), lost companionway boards, or blown-out cabin ports. For offshore work you need to pre-fashion plywood covers and strongbacks or other replacements. For coastal cruising, make sure you have thought through all the answers ahead of time and you have the right tools aboard (e.g. using bunk bottoms to cover large gaps).

Remember that you may be able to mitigate deck opening leaks by changing course, e.g. bear off to minimize the water coming over the deck and level the boat, or tack to make the other side of the boat the higher side.

Don’t Hit Anything Hard

Don’t Hit Anything Hard

While it sounds like a funny line, it is not entirely untrue.

Standing a good watch means you will avoid rocks and, more likely, other vessels. Yes, you may not see every submerged container at sea, or other flotsam at night. But, you have a lot better chance of keeping your hull intact if you keep your eyes peeled. Know where you are relative to rocks and reefs, and where other vessels are. A recent tragedy was the case of a boat that drove onto a steep cliff under power in good visibility. Was the boat on autopilot with inadequate watch-standing? We do not know, as all souls were lost.

Keeping good sea room has come up several times in recent boat losses. Racers tend to cut corners as closely as possible, but it is more seamanlike to give good room to rocks and lee shores, both of which can hole, flood and sink a boat quicker than most of us imagine.

Like many other emergencies, the chance of “Water In The Boat” can be minimized by prevention. We urge you to read other articles on our pages to learn how to deal with water once in the boat. But better to avoid the issue from occurring due to preventable causes!

Sail Safe.

FLOODING: PLANNING FOR AND DEALING WITH A SINKING SHIP

Administrator — Thu, 15 Jun 2017 18:13:56 +0000

FLOODING: PLANNING FOR AND DEALING WITH A SINKING SHIP

Dick Stevenson

Administrator Thu, 06/15/2017 - 18:13

Flooding

Sinking

By Dick Stevenson, s/v Alchemy, NYS, CCA; January 2014

This article outlines a strategy for managing a flooding situation on board your vessel. By flooding I mean any ingress of water which is unable to be stemmed by pumps: i.e. you are sinking. A planned and practiced strategy is crucial as flooding calls for specific directed actions, quickly executed.

I am primarily addressing the typical cruising boat, a husband/wife team on any size boat, although much of the planning can easily be considered for fully crewed vessels. Even if you often have guests, they are unlikely to be helpful in a situation where quick, practised action is necessary.

The Synopsis of this Strategy

The bottom line in a flooding situation is the need to find the flooding and find it fast. As water rises it covers the leak making what was, at first, an easy visual inspection, turn quickly into one done by Braille: by feeling around. Clearly, visual inspection is far quicker and surer. Most of what I suggest is to allow the leak to be found fast.

As a general rule, most of us get less competent in emergencies. Obvious alternatives are not thought of in the anxiety of the moment. Planning ahead, making diagrams and, most important, practicing will mitigate this tendency.

Set up your boat to allow you to quickly find and respond to leaks.

Anticipate vulnerabilities: First, know your boat and try to anticipate all possible areas of vulnerability to flooding. Make a diagram with salient points highlighted.

Make sure all seacocks are accessible and able to be worked by your least strong crew. If there is a seacock which is largely inaccessible, say only by taking apart woodwork or by emptying a locker, consider access cutouts or re-thinking your storage. Relocating that seacock is not an unreasonable choice.

Labelling seacock locations on cabinet/hatch/floorboards can help, especially those vessels with many thru hulls.

Include rudder, drive shaft, and transducers as areas for flooding potential as well.

Track all your hoses, especially those from seacocks. You will find chafe points you can protect, and you can anticipate vulnerable areas such as distribution manifolds.

You cannot do much about your vessel’s sump, but one should keep in mind that the less sump you have, the less warning you will receive and the more quickly water will cover and obscure wide areas.

The same goes for structural “pans” which obscure hull inspection and direct water in difficult to predict pathways.

Early notice: high water alarms* are absolutely essential as they can give immediate warning of any unusual water accumulation. They must be able to be heard in the cockpit of a closed up boat with the engine running. Many a crew has first found flooding by discovering their floorboards afloat. If we have heard the story told, the crew was very lucky. I suspect many who found their floorboards afloat never found it possible to tell anyone their story.

One option is an alarm which sounds every time the electric bilge pump operates from its float switch. We have a dry boat so pump activation is always motivation for bilge inspection.

Another option (and there is no reason not to do both) is a dedicated high water alarm ready to go off when water gets just a scooch higher than the level where your bilge pump activates.

If you have two (or more) bilges it helps when the alarm sounds are distinct for each bilge so as to have an early indication for a search area.

Floorboards: the crucial floorboards for inspection must be able to be removed quickly by the weakest member of the crew.

After a period of high humidity, make sure your floorboards are not too swollen to remove. Shave them if necessary.

Review all floorboards that need to be lifted for a complete flooding inspection. If screwed down, refit to a floorboard lock that is quickly released (a distant second best, store a charged electric screwdriver ready at hand).

Speed: the quicker that the leak can be isolated, the narrower the search area.

Some boats have the engine area bilges separated from the living area bilges. A quick look determines which area is flooding and narrows the search area.

Make separate diagrams as to which seacocks, transducers etc. drain into which bilge area. This is not always obvious, especially with structural pans. One way to clarify is to pour a glass of water near a seacock and track where the water goes.

If you have a “one bilge” boat, consider a dam at a strategic point. It does not have to be high or strong: just a water stopper. Water can and should spill over, but make it high enough to allow alarming it to narrow the search area. **

Pumps: the more water that can be removed from the boat automatically, the more time to find the leak when it is most easily found.

This means electric bilge pumps for most of us.

Pumps benefit from clean bilges, flushed regularly.

They also benefit from good voltage and unrestricted amperage. Review, check and/or upgrade your wiring.

It also means that manual bilge pumps have no place in this strategy:***

They are a dangerous distraction from the main goal of finding the leak and finding it fast.

Most cockpit mounted pumps (with their short 12 inch handle) move only a moderate amount of water and are hard to sustain energetically.

A big pump like an Edson with a 3 foot handle is a wonderful piece of kit, but is still not a wise use of manpower. You do not want 50% of your search capacity (2 person crew) pumping when that pumping is quite unlikely to keep up with sustained flooding and the goal is to find the flooding fast. Two people should be searching for the leak.

2. Refine the strategy for your boat:

a. The alarm indicates flooding. This is one alarm that should get immediate action and the action should be previously thought through and practiced: this is not a time to be spontaneous. One or two floorboard lifts should indicate whether there is a worry and where to initially concentrate your search.

b. From here each vessel’s detailed flooding procedure plan will start to be unique to its own particular design. I am including Alchemy’s flooding plan (shown below) as a way to address the details, the compromises, and some ancillary considerations for this serious event. The following will show how we have taken the above strategy and made an operating procedure for our vessel. Each vessel will differ in the details, but generally the principles will pertain.

Practice!!

There is no way to emphasis this enough. You cannot just write a plan. You must practice using it to make sure your plan works and you can work the plan.

*Easily obtained high water alarms can be had very inexpensively by any vendor who sells household products. These self contained units are often powered by 9v batteries so they are independent of ship’s power grid. They should be tested at regular intervals.

**Often, a natural area for a small dam is where the engine room bilge meets the living area bilge. As said, the dam does not have to be high, but an added benefit is that small inevitable spills of oil, diesel, coolant, etc. stay contained and are easier to clean and less likely to be pumped overboard. They also give quick notice of engine drips/leaks.

***Often articles in magazines reflexively mention manual bilge pumps. I have worried that many boat owners believe going to their manual bilge pumps is a first response to flooding. A casual survey of boat owners seems to confirm this.

Flooding plan for Alchemy:

Procedures to be thought through and practiced in advance.

IS THE BOAT ACTUALLY FLOODING?

Flooding should be first brought to attention by a high water alarm or bilge pump alarm.

Which high water alarm is sounding should differentiate whether the forward or aft section of the bilge is flooding [the bilges are separated and water must reach the floorboards to fall/flow to the other bilge]. If unsure, raise floorboards where engine bilge meets forward bilge (next to galley sink) and see which side is full and/or which way the flow is going. This determines search area.

Test water for salinity; if fresh water, breathe easier (unless sailing in fresh water). Make sure it is not diesel.

IF IT IS FLOODING, then Ginger and Dick work previously determined areas of inspection.

IN GENERAL:

Locating the leak takes precedence over most everything because as the water level rises finding the leak becomes more difficult.

If extra crew, set them up in cockpit with manual pump-handle in bottom step.

THINK! Ask ourselves what has just been done/happened (heard a bump, tacked, started genset, filled water tanks etc.)

Watch footing for holes left exposed by floorboard removal. Not a time for injury.

e.      At some point, earlier rather than later, consider donning life jackets/vests or ensuring they are ready at hand.

f.        At some point, again earlier rather than later, reach out to make contact. This could include:

                                                                       i.      Calling out a Pan Pan Pan and making a report of location and nature of distress.

                                                                       ii.      Hitting the VHF distress call button (DSC button) and hold for 5 seconds--we can always cancel later.

g.       Consider same with EPIRB.

Consider heading the boat toward a grounding place, a beach preferably, and put on speed. (It is likely we will be on autopilot and this will entail only a quick turn of a dial.)

Consider starting the engine as electric bilge pumps will pump more water with increased voltage.

Consider setting up high capacity electric bilge pump (one automatic medium capacity pump is always available). Attach hose (stored in forepeak starboard side under) with quick attachment and put out portlight or cockpit. Tie in place. [Note: a plan is in the works for this to be made automatic as this interferes with the primary task of finding the leak.]

IF FLOODING IS IN AFT BILGE AREA:

Check aft of engine (if clear, then rudder assembly, genset and thru-hulls aft are ok; go to #3), if water is flowing, then:

Turn genset off if it is on, then turn off water for GS at manifold.

If flow stopped, the genset was the problem, if still flowing, then:

Check rudder shaft area.

Remove starboard lazarette.

Rudder shaft, 4 cockpit drains, genset exhaust & propane locker drain should be visible. [On ALCHEMY, there are a number of thru-hulls at or just above the waterline that have no valves (such as the cockpit drains). I consider this a design compromise I am not happy with, but have decided to live with.]

Two areas to check midships aft (that go into aft bilge area).

Three seacocks are under head sink. Turn all off after inspection.

In wet locker and head are 3 thru-hulls just above waterline (electric bilge, scupper, shower sump).

Port side locker has scupper discharge and a no longer used, now plugged, refrigeration outlet

Check engine area for leaks, especially shaft area.

Check engine exhaust and manual bilge pump discharge thru-hulls outboard in engine room.

IF FLOODING IS IN FORWARD BILGE AREA

Check bilge at most forward floorboard for water flow

If Yes, then:

Check and turn off deck wash seacock.

Check depth and speed transducers.

Next is hull integrity.

If No:

Check main seacocks (two, near mast step).

Check distribution manifold (close genset seacock if not in use).

If all ok consider starting engine for mobility and for good voltage for pumps.

Check likely hose lengths for breaks.

Check galley seacock and turn off.

Hanging lockers either side may drain either side of bilge barrier.

Port side also has old refrigeration thru-hull, plugged.

IF NO SUCCESS, CONSIDER:

Checking keel bolts (just one in aft bilge area).

Checking for siphon action: bilge pumps, engines, toilet, galley sink, PSS Shaft Seal bleeding hose, etc.

Checking hull integrity around best guess for ingress.

Tack over to get opposite side out of water.

Checking to see if water level is decreasing with seacocks closed; if so breathe easier as leak is in a hose (and with seacocks closed should stop) and we now have time to find. If not….

Bailing is an option!

Do not stop looking for leak and bailing until water drives you out. The best chance of survival is to keep the boat afloat.

At some point, prepare life raft, grab bags, etc. for abandoning ship, then return to searching.

Hull holing equipment and LOCATIONS

Bungs of various sizes in red bag in bottom step of companionway ladder. (I differ from many by not liking bungs attached to each seacock, although they do have to be very accessible. First, in a flood they may be difficult to untie, see and/or work with if tied to the seacock. They also collect dirt, grime & mold and are continually damp which undermines the swelling expected once banged in place.)

Collision mat in forepeak forward

Emergency Hull Repair Kit with waterproof epoxy near water heater.

1\4” plywood 14”x 3’ under starboard settee cushion with many other various options.

5200 (2 fresh caulking gun size tubes) and sheet rock screws near water heater.

A quite creative suggestion (I suspect from the “old salts” manual) is a lead sheet, pre-perforated, with sheet rock screws.

C. Seacock and thru-hull locations (The bag of bungs is in the bottom companionway step). (In our safety manual, in addition to the above text, there are 2 pages of diagrams, port and starboard side, giving visual indications of where the thru-hulls exist.)

1. Hull openings below waterline: 7 seacocks (listed below) plus propeller shaft and two sending units for instruments (under floorboards forward of table).

Two seacocks under floorboards in front of mast.

One in the port side forepeak bilge locker under cushion in middle.

One under floorboards near galley sink.

Three under head sink.

Numerous hull openings just above the waterline, again see diagrams.

Diagrams of (manufactured) openings in Alchemy below.