Holding tank

Cardo

Cardo

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In a plastic tub!
www.yacht-tinkerbell.co.uk
And another question!
From what I gather, some boats, such as the new Bavarias, have holding tanks into which dirty water from sinks/toilet/shower go into. This tank can then be either flushed into the sea, or pumped out at a marina. Is this correct?

If it is correct, is this something which most boats have? Or do some boats flush the dirty water direct to the water every time?
eg. does an older boat, such as a 1988 Moody 346 have such a holding tank that can either be flushed into the sea, or pumped out at a marina?

Cheers!
 
My understanding is that any new boat sold with a toilet has to have a holding tank for waste water. Clearer many older boats have already had holding tanks fitted. I don't think this stops people retro fitting 'standard' sea toilets.
 
Bavs holding tanks are utilised only for toilet waste i.e."black water" and not linked to the sinks "grey" water wastes. I think it unlikely that both would go to same tanks because of contamination issues.
Standard fitting of holding tanks is a relatively new development - some older boats have them retro fitted especially when used in countries such as Turkey and USA where heavy fines have been imposed for some years for discharging foul water in harbours.
 
As far as I've been able to learn, there is no requirement to hold gray water (galley, bath and shower water) in the new EU requirements, only black water (toilet waste and flush water). Gray water can continue to go directly overboard.

In waters where holding tanks are required, ALL boats will required to have 'em--local and transient....which means that owners of older boats and/or anyone with a boat of any age not already equipped with a tank will have to retrofit.

In most cases, this means that builders will be required to install them in all new boats immediately...there'll be a deadline for all existing boats to be in compliance.
 
So if a description of a boat says it has a "marine toilet", does this suggest the black water is flushed direct into the sea, or into a holding tank?

If older boats need to be retrofitted with holding tanks to comply with regulations, how easy is this to do? Has anyone done it to their boat?
 
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surely the holding tank,you refer to is for Black water.there are very few boats with grey water tanks (except propobally in Turkey).Grey water discharges are reportedly much more disastrous to the enviroment.

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Hmm, I'm sorry, but your post confuses me. You're saying that grey water (dirty water from shower, taps) is very bad for the environment?
 
Yes of course. "black water" which by the way is usually BROWN. is totally organic, when you flush there are a load of fish waiting in line to 'recyle' it into your next dish of 'fruits de la mare'

"Grey water" has all that horrid stuff that you used to clean the pans/oven/etc with.
 
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So if a description of a boat says it has a "marine toilet", does this suggest the black water is flushed direct into the sea, or into a holding tank?

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"Marine toilet" only refers to the type of toilet. Although the piping from it can go directly overboard OR into a tank (or be plumbed to do either at will), I suspect that if a boat is fitted with a tank, it will also be included in the description.

You also asked: "If older boats need to be retrofitted with holding tanks to comply with regulations, how easy is this to do?"

It's not that hard to do, though it can be highly labor intensive and has been known to add quite a few inventive new combinations to owners' vocabularies of profanities. We've had laws on our side of the pond requiring all boats to retrofit for more than 20 years (it was the need to learn how to do so in the mid '80s that accidentally started me down a new career path). For a good overview I suggest you go to the Tek-Tanks site and read the sanitation system guide: http://www.tek-tanks.com/sanitation/sanitation_index.html

As for the environmental impact of toilet waste vs. gray water...toilet waste is loaded with e-coli and other harmful bacteria and virii...none of which are in gray water. With the possible exception of any oven cleaners, there's nothing in gray water that you haven't either washed in, brushed your teeth in, or eaten everything except what's left on the plates or in the pans...how harmful can gray water be??? And even oven cleaner can't be any worse for the environment than many things used to wash boats, clean teak and most bilge water.
 
The tank should be within 6' of the toilet...it does not have to be lower than the toilet...in fact, almost none are on sailboats. So depending on where the head is located, the most common locations are in a settee, under a v-berth, in the bottom of a locker or in a cockpit locker. On powerboats, most are in the engine compartment...although if the head is forward, under the v-berth is the best location. Under the cabin sole is the WORST location for a waste tank...it's a fine location for water or fuel, but not for waste. The sanitation guide on the Tek-Tanks site explains why.

When installed and plumbed correctly using the right materials and properly maintained, odor from a tank located in the living space should not be an issue.
 
We've retro-fitted holding tanks to both toilets in our 1989 Moody 422, as we intended-and presently are-sailing in the med.
The tank for the aft heads has been made to measure out of stainless steel, and fitted inside the hanging locker in the aft cabin. The loss of storage space has not been a problem in our case, we use the sea-berths for storing our clothes etc, and I never understood why one would need to hang things up on a boat:do you know anyone who sails in a dinner-jacket/partyfrock?
Anyway, back to our holding tank: the main body of our aforementioned aft tank is above the waterline, and the outlet is just below the waterline, which makes it VERY easy to empty: just open the cupboard door and turn the seacock open, and WHOOSH! gravity does the rest. No pumping or sweating, just open the seacock, count to ten, close the seacock and you're done. If there's one thing we've learnt, it's that things have to be quick and hassle-free, otherwise they don't get done as often as they should, disciplin starts to slacken, and before you know it you've got a blockage or a leak...
The forepeak holding tank is a conventional pumped-out, "keep-fit" one, under the v-berth, with pump & seacock under the saloon seat next to the mast, if anyone's interested I'll happily tell you more!
 
I am really alarmed. Are you telling me that ALL boats with sea toilets MUST be retro fitted with black tanks? When did this regulation come in?

I have a 1 year old boat and I was never this when I bought it.

Not only that, but there is absolutely nowhere on the boat (22 foot) to put a holding tank, unless I removed the toilet or put it on the foredeck or wheelhouse roof.

Maybe I can get one of GC1's sea trailers and tow it behind!
 
It's possible to find room for a holding tank on a 22' boat, but it would mean giving up at least 1/3 of your available storage to the tank and related plumbing. So the only practical solution on a 22' boat--on ANY boat under about 26'--is to replace the sea toilet with a self-contained system...essentially a portapotty, but permanently installed (though some models allow you to have it both ways, pumped/dump OR portable), fitted for pumpout and dumping at sea.

That's actually a better solution than it may seem, 'cuz there's virtually no plumbing to maintain, no toilet pump to maintain...the 5-6 models hold about as many flushes as 15-18 gal tank connected to a manual sea toilet. And because they must be vented same as any other tank, it's much easier to prevent odor in them. The only real downside is, they can't be bypassed. But a y-valve and pump to the thru-hull solves that problem.
 
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I am really alarmed. Are you telling me that ALL boats with sea toilets MUST be retro fitted with black tanks? When did this regulation come in?



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Don't be. No. And it hasn't.
 
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Quote:
I am really alarmed. Are you telling me that ALL boats with sea toilets MUST be retro fitted with black tanks? When did this regulation come in?

Don't be. No. And it hasn't.

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Only just read this. Phew! And to think I was just about to go on the run as a fugitive.

Putting a holding tank in a small boat is daft, it is actually 21 feet, and a porta potti would be a huge problem as there is no disposal at my Marina and I don't fancy lugging it up from the boat every few weeks to take home.
 
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