Shower water into the fosse or not?

Hello all,

Moving a bathroom and would like advice on whether the shower waste can/should go into the fosse? We have a grey water system but haven't got sufficient fall to reach it and still stand up in the shower! The soil pipe is not far....... Any experiences?

From what I understand, we are supposed to put all of our waste water into the general drains which run down the street, were laid down in the 50's and which have subsequently collapsed with the passage of heavier vehicles as time has progressed...maybe that's why the town hall isn't pushing for anything to be done...or maybe its also because they erected a substandard pavement with a spring collector (which comes from my spring overflow) which then flows into the street drain uphill and consequently pools outside my gate...oh, the joys of having leverage !

We have only just had a new fosse installed (whole process subject to SPANC inspections and approval) and all household water has to go straight into the fosse; toilet, shower, sinks, bath.

Rgds, Mike L

Back at the beginning was assuming it is an old one, which is what we have. It does not make life easy BUT the cost of replacing it, hmmmmm.

Is it a modern fosse septique or an old one?. Modern ones are "toute eaux", and have sort of prefilter/fat trap built in, which has to be changed regularly. Old ones, like ours, often are split in two - a WC fosse and a "grey water" fosse. Personally, I think the latter system is better as the washing detergents, bleach, etc do not interfere with the WC bacteria, unless, of course, you put bleach in the WC.

A fosse toutes eaux with a bac between it & the kitchen does it for us. I installed the system with a single stack drain serving 3 bathrooms & a downstairs toilet & scullery about 7 years ago & no problems so far. It passed the last control without problems. Probably due for it's first empty out now but still producing clear water at the drains despite us chucking god knows what down it. The bac gets cleaned of grease about every 6-8 weeks. Never bothered with fancy stuff to "keep it working". It just does:-)

If you find such a device let me know Sara.

Insomnia is a wonderful thing, I used the time to plough through the SPANC website (and yes, I dropped off a treat then). When the time comes we will be required to install a fosse toutes eaux to take all household water.

I also did a lot of research on septic tanks and, so long as we do not overload the system with water and use bio detergents the fosse should be fine. So, given that we or our successors will eventually have to do this we may as well put the appropriate pipes in now as digging up a concrete kitchen floor is not a thing to be repeated. Do it once, do it right!

My next insomnia session will be taken up with researching a gizmo to prevent smelly blow back into the shower!

Ideally you'd want to recover the grey water from the shower but if that can't be done there is no problem with it going into the fosse. There really is a lot of nonsense talked about what you can and can't put into a fosse system. True, bleach kills all known germs dead ...but only if a lethal concentration is achieved. You'd have to using many litres on a daily basis to achieve that! The odd squirt of supermarket bleach or toilet cleaner will have little or no effect. Nor will modern washing detergents they solved that problem years ago. I think the French are trying in their own way to sort out the problem of of excess BOD in the water course by strengthening fosse regulation and forcing communes to put more houses on town drainage systems. Albeit in little steps and with much protest from those that have to pay. The problem of the fosse close to a river that was mentioned will of course be a much more sensitive problem that would require a bio-digester.

The principal function of a bac a graisses is to intercept large quantities of fat that would otherwise end up in your fosse septique and potentially block it up. Hence one has a grease trap between the kitchen outlet and the fosse. Periodically if you are so minded you can remove the now partly solidified fat from the trap though as both inlet and outlet sit beneath the grease layer there is little risk of a real blockage. Our WC waste from upstairs goes direct to the fosse toutes eaux together with the waste from hand basins and shower. We have a bac a graisse between kitchen and fosse toutes eaux. Waste from the WC on the ground floor goes direct to the fosse toutes eaux but waste from ground floor shower, hand basin and washing machine goes via the bac a graisse. This last was only fitted because it was too far from the fosse toute eaux to the principal source of grease ie the kitchen for the kitchen sink's effluent to go straight into the fosse. Hitherto the effluent from the fosse toute eaux went direct into a small plateau d'infiltration; We have now retrofitted a Biorock Filter to improve the quality of the final effluent. All in order according to SPANC except that they want us to install an additional air vent to the fosse toutes eaux. From time to time we have some smell in our downstairs bathroom; Largely caused by some drains siphoning out water from shower traps. Unfortunately the French seem incapable of adopting a single stack waste system. If only they would concentrate on the BOD of what goes into the ground/watercourse but they are obsessed with a theoretical system not how effective or how non polluting one's arrangements are. I dare say that when we had no waste disposal at our house save me digging a big hole to dump the contents of the Elsan we were far more polluting than now.

I have marsh marigolds too, mollyblobs as they are called in the east of England. First year the irises and them have been so good. As for the water, well SPANC where Andrew is, where I am and you are might as well be on different planets to begin with probably ;-)

Thanks Brian, you've confirmed what we thought, ie that the detergents going down would probably trash all the little enzymes in the fosse. We have a multi chamber then filtration bed for the grey water and my flag irises are spectacular this year! I shall just have to wait to be SPANCed and then install a fosse toutes d'eau, probably.......until then , a saniflo pump.

spanc still telling me here that everything must go to the fosse, passing through a bac between the house and the fosse...?!

Andrew, hmm. Things are changing too fast perhaps. My OH has SPANC following a sale she has going through where the vendor has to have the bathroom and kitchen water to the fosse, which were exactly to regulation when they had the fosse installed, changed to take the bathroom and kitchen away for which I am not sure what they have to have installed but something for sure. She has nowhere permissible because she is on a riverbank. The outflow is not allowed to pollute the little river. The vendor is fuming because they paid out after buying, now she wants the sale through quickly (her husband died in the place a few months ago, so understandable) but now she has to pay out again before she can sell. My OH checked thoroughly and that is they way it is now. No change from us but still as vague but fosse is out.

Sara, we had a British plumber who has been here longer than he ever worked in the UK and knows his stuff better for here than there. He not only advised but showed me some stuff showing French regulations online. I installed a bac degraisseur as a result, so that all bathroom, kitchen and washing machine in the cellar water goes there and only the fosse water overflow feeds in. The bathroom had previously been fed into the fosse.

As much as anything else, it is what we use in the shower, be that hair shampoo, body lotion or whatever and the cleaning products that should never go into the fosse which would damage or kill the enzymes that break its contents down, otherwise it would be a nasty noxious, smelly mass that would be impossible to pump out and then use for (?). Hence never use bleach or abrasives to clean the loo. The products like Eparcyl are for that.

OK, the bac. Well all the bathroom, dishwasher, washing machine and other things end up flowing into that then through and on into the ground. I never really saw the point because it all seems to go to the same place and a soil pipe would seem to be adequate. However, since I added filtration myself I now have a nice wetland area with irises, bullrushes and other things growing in it. Mind you, even then I was told the SPANC people will not like seeing the wetland if we ever sell.

So, shower water down the fosse. No. What to do with it? Apart from the regulations that seem pointless I have never actually had a straight answer!

It should go into the fosse septique...