Number of water systems on a sailboat

[davidpm]

I was trying to explain to a person new to sailing why a sailboat was different than a car or house. As an example I thought it would be fun to tick off the multiple water systems a cruising boat will typically have. I defined a system primarily by its purpose. For example I counted the fresh cold water one system even though there may be a run to multiple sinks. I counted the fresh hot water as a separate system because it is optional, some boats have only cold water, and it is a separate loop with the heating components. So here is my list. I think it is surprisingly long. For those who may be unfamiliar with the risks I’ve also mentioned why some systems need to be checked.
Of course my choice to call something a separate system is arbitrary but perhaps a useful checklist.

Cockpit Drains
Many cockpits have drain holes that connect to a hose that go to above water thru hulls with no seacock. If that hold fails rainwater can lower the boat enough so the thru hull meets the water line then the boat sinks.

Cold Fresh Water System, Power
Tanks, Tank connecting manifolds, piping to sinks constitutes dozens of connectors and fittings. A failure can empty a freshwater tank into the bilge.

Cold Fresh Water System, Manual
Many boats have a separate manual pump for fresh water for convenience to save the trouble of flipping on the water pressure switch to rinse one dish.

Sea Water galley sink pump.
Some boats have a separate manual pump for sea water to save water rinsing dishes.

Hot Fresh Water System
Some kind of hot water tank is common again with dozens of connectors and fittings.

Raw water intake for head

Black water discharge of head

Gray water discharge from sinks

Automatic Bilge dewatering system

Manual bilge dewatering system

Raw water intake and exhaust system for engine

Stern shower system.
I make this separate because it is optional and easily forgotten.

Water tank filling system
I make this separate because it is optional and easily forgotten.

Stuffing box drip
This is a stretch to call a water system but it is important and water does flow so I’m including it.

Engine coolant system

Ice box drain

Air Conditioning drain

So that’s it folks, seventeen water systems on a craft with the usable space of your kid’s bedroom. That doesn’t even count the propane, fuel, Freon and other systems. Few boats will have them all but a failure of any system with be annoying at best and catastrophic at worst.

My point wasn't that this was bad just that their is a lot more to a boat that might be evident at first look.

Did I miss any?

[sfchallenger]

I've explained the survey process to non-boat types like this. It's a little like a home inspection, except that an overlooked problem with your house isn't likely to kill you in a hurry.

[DWJensen]

Nice list, never really sat down and thought about how many different things there are.

If you have an A/C drain you'll also have an intake. Black water should also include holding tank, macerator, etc.

Also, if you're going to count optional systems, then don't forget to add:

• Watermaker system (including intake, lines, fittings, pump, membranes, and brine discharge)
• Washdown pump system

Daz

[Squidd]

Hot Tub...!!!

[tdw]

David,

Here is one to add to your list and this is a design element that I cannot understand.

Maybe Bob Perry could comment.

I've noticed on many boats, and boats of seemingly high repute - Valiant, Passport, Malo, Hallberg Rassey to name just a few that deck drains go through the deck into the interior of the boat and then by hose pipe to a through hull further aft, often linking up with other through decks as they go.

Not only do you end up with a hole in your deck for seemingly no good reason but this is compounded by a number of further hose connectors.

Why ? I certainly have no idea.

Cheers

A

ps - everyone should keep an eye on the behaviour of any non return valves and/or manual bilge pumps. Recently we have had one NRV fail allowing bucket loads of water to spurt up through the head sink outlet and a manual bilge that should have an NRV but doesn't and is back siphoning when we are heavily healed. To be honest the outlet for the pump is located in a really stupid position. If it was where it should be there would be no need for an NRV at all. I do stress however that the problem only occured when we were getting slammed about by a nasty cross seaway whilst already hard on the wind. There would be very few occasions when she would be that far over on her ear but even so aren't we supposed to be concerned about worst case scenarios ?

[davidpm]

Originally Posted by tdw

David,
Recently we have had one NRV fail allowing bucket loads of water to spurt up through the head sink outlet and a manual bilge that should have an NRV but doesn't and is back siphoning when we are heavily healed. To be honest the outlet for the pump is located in a really stupid position. If it was where it should be there would be no need for an NRV at all. I do stress however that the problem only occured when we were getting slammed about by a nasty cross seaway whilst already hard on the wind. There would be very few occasions when she would be that far over on her ear but even so aren't we supposed to be concerned about worst case scenarios ?

Those are interesting issues.
Just when you are the busiest and or sickest some crazy design flaw hits you.

[Bene505]

David,

Great list! Three comments:

1. I'd split the manual and automatic bilge dewatering system into

automatic electric
manual switch driving electric
manual (as in your arms get tired)

We have the second one, which is an electric pump that can get that last ounce of water out. The third one is arm-operated back at the helm.

2. Some refrigeration systems are water cooled.

3. Wash down pump like we have at the bow for hosing down a muddy anchor and washing down the deck.

(4. It's stretch, but a trash pump could be carried aboard.)

Regards,
Brad

[olson34]

When it (occasionally) seems like a good idea to try to explain to non-boaters explain why my boat takes a lot of time -- not to mention money -- to "maintain" it's systems, I tell folks to imagine living in their land home with THEM providing ALL of the utilities that on land a city or county or utility does for them.


At home our city sees that water is piped in reliably, sewage is piped away reliably, utility companies make sure that all phone and 'net access is maintained, and the electric utility makes darned sure that we have reliable surge-free power 24/7.

Often this makes "the light go on" in their imagination.

All that difference plus no economies of scale... like my boat's refrigeration installation that cost about a thou and my labor took a week. For all that $ and labor-$-equivalent at home I could have one of the finer fancy fridges on the market! Compare all that luxury to a boat fridge with under 4 cubic feet.

That thousand $ range on the boat with the little oven? For about the same $ the house gets a countertop range and a wall oven.

And, so it goes.

When we pull up in our driveway and open the garage door with a click and turn on lights with another click, MUCH is taken for granted compared to living on our Floating Vacation Home.

Love the boat. Love the "sailing life"... but there are compromises...

Cheers,
LB

[Bene505]

... more

Stuffing box drip
This is a stretch to call a water system but it is important and water does flow so I’m including it.

Dripless ones have their own through hull and hose, that is definitely a water system.

(I worried about this when on the hard in the winter, but the shaft being angled downward, I'm told all the water drains out.

Regards,
Brad

[Bene505]

more...

Shower sump dewatering system

Having a stand-up shower often means that your feet are below the water line. Hence the need for a sump and a system to dewater that sump.

Regards,
Brad