Etiquette/Laws on Holding tanks

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ylop

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I've never been the lucky person to deal with holding tanks before (I've had joys like cassette toilets, or no toilet so not that lucky!). What are the rules / etiquette / good practice* on when holding tanks are opened/drained? How long with say 4 adults on board can you normally last before needing to empty the tank? How often (if at all) are yachts actually pumping out (a quick look suggest not that many UK marinas have facilities) rather than just discharging at sea (e.g. are most boats on the clyde far enough off shore?). Finally - if ever there was a task that was likely to make you feel sea sick, it is surely crouching upside down with your head in a dark damp locker whilst underway trying to reach the stupidly positioned seacock - is it common to fit some sort of electronic remote activated gate valve?

*I'm particularly interested in the UK, but feel free to highlight areas with differences
 
Depends on size of tank obvs, but we could manage about a week with 2 adults two kids. Big difference if you ONLY use the tank for poos. Wees go straight over. Try to use shore facilities when possible.

I happily flush the tank a mile offshore. Many jurisdictions say three. In my understanding the ecosystem can process it as it's tiny quantities, colossally diluted. Compare to the volume of seagull and fish poo/carcasses.

Also bear in mind the tide acts as a flush. The Solent for example gets near as dammit flushed twice a day. And no, I don't flush poos in the Solent, I take them outside....but if I was desperate on passage with a full holding tank, I would do it and not worry too much.

There are people living aboard at anchor / on moorings all over the world. Most of them might admit they drop it in the bay in the small hours. We just returned from the Caribbean, where (although again I don't recommend it) we knew it was happening in places like St Anne's and Prickly Bay, it wasn't the conspicuous problem you might imagine.
 
The amount of sewage that small boats do/could discharge in UK waters is miniscule compared with the vast quantities of untreated sewage that water companies are allowed to discharge into our rivers and seas by our useless government. Rather than worry about boat output, email your MP to demand action to stop the water companies from polluting our waters. Once that's been dealt with, then will come the time to worry about the impact that small boats have.
 
Not aware or any national regulations otherwise seatoilets would be an issue. However, be aware of local regulations & Ts & C's.

As to etiquette. I would say empty at the point that you are furthest from land and ideally when the tide will take it away. Avoid flushing the tank when moored on a river with the tide flooding!
 
ylop said:
I've never been the lucky person to deal with holding tanks before (I've had joys like cassette toilets, or no toilet so not that lucky!). What are the rules / etiquette / good practice* on when holding tanks are opened/drained? How long with say 4 adults on board can you normally last before needing to empty the tank? How often (if at all) are yachts actually pumping out (a quick look suggest not that many UK marinas have facilities) rather than just discharging at sea (e.g. are most boats on the clyde far enough off shore?). Finally - if ever there was a task that was likely to make you feel sea sick, it is surely crouching upside down with your head in a dark damp locker whilst underway trying to reach the stupidly positioned seacock - is it common to fit some sort of electronic remote activated gate valve?

*I'm particularly interested in the UK, but feel free to highlight areas with differences
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The most common size tank in say 35' production boats is 60l. Single use of a Jabsco to flush the pipe to the tank is around 2l (obviously length of pipe varies) so maximum is 30 uses, so 4 people once a day = 7 days. In reality it is less than that. In UK coastal cruising with periodic stops at shoreside facilities holding tanks get very little use. Try to do poos on shore, but if doing them into holding tank say at an overnight anchorage then empty as soon as you sail away in the morning. No reason to hold just urine in the tank except in a marine - but then you can use shoreside. Simple gravity tanks are the easiest to live with, although it helps to have a diverter valve so you can go direct with the tank closed. Always flush through with fresh water and leave the tank empty and seacock open when you leave the boat.
 
coveman said:
What is the reasoning behind leaving the seacock open?
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Just habit. Never bothered to close the seacocks as it is illogical. If the hose and attachment are sound what difference does it make? Failures of seacocks are extremely rare and usually it is the through hull that fails through dezincification and then being subject to force so it does not make any difference if it is open or closed.

I know many people express horror at leaving them open but are quite happy leaving cockpit drain seacocks open (otherwise the boat might sink because the cockpit can't drain) but I have never found evidence that boats sink because loo seacocks re left open. Much more important to exercise them regularly so they do not stick.

Larger modern boats have between 10 and 15 seacocks and there are tens of thousands of them in use. When did you last hear of a boat sinking through a seacock being left open?

There are all sorts of rituals in boating that are not based on facts or evidence or derive from boats and practices that are not relevant to modern boats, fittings and materials.
 
This question of holding tanks reminds me of a tale that I was told by a yacht maintenance guy. In the marina, which is in a locked in basin, was a 50+ft motorboat. They found the toilets onboard had stopped working, so called the maintenance guy to come and have a look. He realised they had been using the holding tank for some months and it was full, hence the toilets would not work. As it was late in the day he told them to use the marina facilities and he would come back in the morning to take the boat out so the holding tank could be emptied. When he returned in the morning, the owner said everything was fine as he had emptied the holding tank overnight into the marina basin. This was contrary to the marina rules and might be why the boat was shortly moved elsewhere.

With regard to discharges into rivers, the amount of sewage discharged by leisure yachts and motorboats is far less than the number of houseboats that are permanently discharging straight into the river. On the River Medway there must be about 1000 houseboats along the tidal section. At Hoo there are about 120 and just downstream is Hoo Marina. As the area dries, it can stink terribly besides what floats by. I met one man with a small boat in Hoo Marina who dropped a tool into the mud when the tide was out. So he just reached over and pulled it out and cleaned his hand up with a cloth before continuing to complete the job he was doing. Within a couple of days he was admitted to hospital with sepsis and he stayed in for over a year. When I met him some 6 months after leaving hospital he still was not back to full health.

On Concerto I have a holding tank that was probably fitted in the 1980's. It has diverter levers to direct any discharge to the tank or sea and a separate bilge pump to empty the tank. I rarely use it. If I am in a locked in basin, I always use the shore facilities. As a supermarket says, every little helps.

The health of our rivers is still far better than they were 50 years ago and they are closely monitored constantly. How the water companies can still discharge untreated sewage into a river is beyond me. This is still the greatest problem that should be rapidly improved, but I am a realist I believe they can never achieve a 0% discharge. Then houseboats should be connected to the main drainage system. The amount of effluent from leisure yachts is such a small percentage of the the total discharged into rivers.
 
The medina is certainly much changed from 30 years ago. Then, I recall a friend having a close encounter of the turd kind whilst clearing a rope from his prop before the start of the RTI race. His mooring was a few hundred metres from ours now.
 
In the early 90s me and friends used to jet ski off Clacton, the stand up type not the sit on top and inevitably we'd swallow water when we fall off. We'd usually feel rough afterwards. I later learned of the Bovril Boats which surprisingly have a wikipedia entry and were still dropping till 1998 Bovril boats - Wikipedia They might have dropped on the ebb but didn't they realise the tide comes back again? Was that why we'd feel ill?

A quick search finds people are still getting ill at Clacton so maybe it wasn't the boats? this from 2018 Why you should never swim at this area of Clacton beach - Essex Live this from 2019 Essex beaches LIVE: Updates as public warned not to swim at Clacton, Frinton and Walton - Essex Live

All the thousands of leisure boats in Holland had sea toilets regardless that they were used inland often in meres with very minimal water movement where people were swimming and presumably it wasn't a noticeable health problem.

I'm not sure what to think about it. Now with holding tanks I guess we have made it more difficult. Instead of a single turd being discharged we've created thousands of mini bovril boats dropping 60l of sewage in one spot. Progress!! The etiquette should be wait until you are going at speed so it is at least dispersed a bit.
 
jac said:
Not aware or any national regulations otherwise seatoilets would be an issue. However, be aware of local regulations & Ts & C's.

As to etiquette. I would say empty at the point that you are furthest from land and ideally when the tide will take it away. Avoid flushing the tank when moored on a river with the tide flooding!
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I believe there are rules which vary slightly from country to country. Below is a link to the RYA site showing some European countries and no doubt somewhere on their site are the UK rules, I believe it used to be beyond 3 nautical miles for the UK and has been for many years but rarely gets mentioned or discussed .

Prevention of Pollution by Sewage from Ships
 
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Interesting responses. I'm both pleased that I haven't missed some essential bit of knowledge that everyone else has and at the same time a bit disappointed that the answer (people will publically admit to) seems to be - don't worry about it, compared to the water companies you are nothing. I'm guessing that means lots of people actually privately say, "nobody will know, and I'm not that big a problem" so just leave the sea cock open at anchor, mooring or maybe even in a marina? Its a bit like my mother pouring used cooking fat down her sink and saying so long as I flush it through with a kettle of water and a squirt of fairy it doesn't block the pipes. I guess similarly old habits die hard so even if people know they shouldn't they likely will for a generation.

Now with holding tanks I guess we have made it more difficult. Instead of a single turd being discharged we've created thousands of mini bovril boats dropping 60l of sewage in one spot. Progress!! The etiquette should be wait until you are going at speed so it is at least dispersed a bit.
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OK that seems logical, along with the further from shore the better stuff. It would also seem that a nice choppy day is better than a flat calm one to mix up the discharge quickly... but that brings me back to my supplementary question in the OP. Does everyone just open the sea cock manually or are some people making that a simpler task when the boat is rocking/rolling etc?
 
Bilgediver said:
I believe there are rules which vary slightly from country to country. Below is a link to the RYA site showing some European countries and no doubt somewhere on their site are the UK rules, I believe it used to be beyond 3 nautical miles for the UK and has been for many years but rarely gets mentioned or discussed .
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Ahha - a bit of effort to find but uncovered this: waste-management
Suitably ambiguous with a "no rules for pleasure vessels" then "holding tanks should only be emptied three miles from land". I'm guessing most boats in the Clyde have an issue there - as they'll need to get to south of Ardrossan/Brodick before they should open the sea cock! Most boats sailing out of the Argyll/Lochaber marinas etc must have similar issues... as you'd need to be south of Mull or round Ardnamurchin point before you were that far off - basically the areas people typically avoid in poorer weather. I'm quite sure that the majority of those people sailing the Kyles of Bute or Sound of Mull on a weekend are neither holding on to go ashore, nor going to the very limited pump out options. I understand why the RYA would follow an official line that's the same as commercial vessels, but I wonder if it actually means lots of people just leave the tank flushing to sea even in anchorages?
 
ylop said:
Ahha - a bit of effort to find but uncovered this: waste-management
Suitably ambiguous with a "no rules for pleasure vessels" then "holding tanks should only be emptied three miles from land". I'm guessing most boats in the Clyde have an issue there - as they'll need to get to south of Ardrossan/Brodick before they should open the sea cock! Most boats sailing out of the Argyll/Lochaber marinas etc must have similar issues... as you'd need to be south of Mull or round Ardnamurchin point before you were that far off - basically the areas people typically avoid in poorer weather. I'm quite sure that the majority of those people sailing the Kyles of Bute or Sound of Mull on a weekend are neither holding on to go ashore, nor going to the very limited pump out options. I understand why the RYA would follow an official line that's the same as commercial vessels, but I wonder if it actually means lots of people just leave the tank flushing to sea even in anchorages?
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Yes it can be a long journey to the waste disposal grounds. However there are no restrictions other than modesty to peeing over the side and you could always fir a Thunder Box on the stern for the number two's. Whales do it... Porpoises do it. so why can't sailors do it ?

I am just the messenger. Actually rules came into place all over Europe possibly as far back as 1997 and I remember discussing this topic at the time with the Headmistress when I made exactly your points and also the fact that in general no one here seemed to be aware of the rules which were not being publicised or enforced. :) At that point the USA rules were becoming strict and being followed and I believe one or two UK sanitation companies discussed the matter with her in anticipation of what was happening here . I suspect for many years most of them mainly dealt with inland waterways vessels. However companies such as Lee Sanitation are now probably seeing a lot more business from seagoing leisure craft many of which are delivered with holding tanks while more and more older vessels are having them installed. Some marinas are even fitting pump out stations.
 
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Bilgediver said:
Yes it can be a long journey to the waste disposal grounds. However there are no restrictions other than modesty to peeing over the side and you could always fir a Thunder Box on the stern for the number two's.
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Whilst you may persuade half the crew, the other half are less likely to agree! I guess if we were looking for basic amenities we wouldn't buy boats with nice heads etc.
Whales do it... Porpoises do it. so why can't sailors do it ?
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I genuinely have no idea if Whale or porpoise poo is likely to be infectious to humans (or other animals). I do know that they don't use toilet paper though - it would get soggy when they were swimming around!

Actually rules came into place all over Europe possibly as far back as 1997 and I remember discussing this topic at the time with the Headmistress when I made exactly your points and also the fact that in general no one here seemed to be aware of the rules which were not being publicised or enforced.
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Because they are not rules applicable to pleasure craft?

Some marinas are even fitting pump out stations.
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Yes I found a map (don't be tricked into thinking every marina on the map has pump out - you have to click to see if its chemical toilet / pump out / etc facility they have.
UK Pump Out Locations – The Green Blue

Only 2 marina's on the Clyde have pump out! None in the Oban area! [Scottish Canals do have pump out]

However perhaps most usefully it does clarify that in the UK for pleasure boats it is a matter for individual judgement, outside specific areas.

SO I think clear that very few people are pumping out routinely. Hopefully they are all closing the seacock in Marinas. So back to my original two questions: how far from land do most of you get before dumping the tank AND do any of you find that is vomit inducing and it would be easier if you could do it at the flick of a switch?
 
All new boats are fitted with holding tanks (since, from memory the 2011 RCD revisions) but of course there are thousands of boats where it is difficult or impossible to fit one.

However this is a classic case of making something "everybody's problem" when it is specific to localities. Discharge from yachts in tidal water is not a problem, but it is in enclosed waters or crowded moorings. As several have said once you understand this it is not difficult to minimise the impact of your own body waste when sailing in our coastal waters. of course there are many parts of the world where there is a problem and not unreasonable to have legislation to deal with it.
 
ylop said:
SO I think clear that very few people are pumping out routinely. Hopefully they are all closing the seacock in Marinas. So back to my original two questions: how far from land do most of you get before dumping the tank AND do any of you find that is vomit inducing and it would be easier if you could do it at the flick of a switch?
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I usually open the seacock just before entering the harbour (Poole) or at other locations while still in tidal streams. Never had any problem with just turning the handle, or pressing the macerator button with a pimped system.

People seem to forget that you are not discharging solids but 90% liquid with well ground up mater in suspension.
 
It does contrast somewhat with Türkiye where you buy a Blue Card which is programmed with number on board, tank size etc. and is used to authorise pump outs.

Auto fines if you don't pump out as often as they think you should.
 
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