A guide to septic tanks or fosses septiques in France
The chances are that when you lived in the UK you will have had a mains sewage system that took all your household waste water away. You probably never had to think much about what happened after you let the water out of the bath, unplugged the sink after the washing up, or flushed the loo. It's not really something that many of us want to dwell on anyway! Your move to France, however, or your ownership of a French holiday home may introduce you to the delights of the fosse septique, or septic tank, which is very common in France, particularly in the rural areas where so many of we Brits choose to live.
These are two realistic and approved alternatives to mains drainage, and these are both commonly found in rural France. The first option is a cesspit. This is becoming less and less popular, and unless there is no possibility of installing a septic tank instead (lack of space being a problem in some small villages where houses do not have gardens), the use of these is now being discouraged. A cesspit is, in essence, simply a storage tank for waste. It does not treat the waste in any way, and therefore it needs to be emptied on a regular basis. Cesspits are also prone to producing some quite unpleasant aromas!
The second, and more widely used choice in France is a fosse septique (septic tank), or a fosse toutes eaux (tank for all waters). These are actually treatment plants for waste water and solids from kitchens and bathrooms. Unless you live in a town or village in France where mains drainage is viable and has been installed, it is highly likely that your French property will be equipped with this type of drainage system.
You have to live with it, so you may as well learn to love it. It may not sound appealing, but a properly installed and maintained septic tank is actually a very efficient domestic drainage system. If you are buying a property, make sure that you check all the details of the septic tank, from the type of plant that it is, through to its installation date and ask to see all the certificates of maintenance works, such as drainings, emptyings or inspections. Septic tanks or fosse septiques are now covered under a set of legal requirements (new laws were passed in 1992) which are overseen by the Mairie, whose responsibility it is to make sure that you carry out all the necessary work. This includes having a four yearly inspection (the Mairie will contact you when this is due) and running a series of regular checks yourself in the meantime to make sure that everything is functioning as it should.
A septic tank is a fairly basic treatment plant. It separates the water from the solid waste, and allows bacteria to consume a portion of the solids. Before the instigation of the new regulations, it was quite common for the water (from baths, washing up etc.) to be allowed to drain straight into the soil, bypassing the tank, but this is no longer permissible. All waste water now must be treated in an approved manner before being allowed to pass into the environment. Once the waste has been collected into the tank (it may, in some cases, have to pass through a grease trap first) it separates into three layers, these being the scum layer on the top, the liquid layer in the centre and finally the sludge layer on the bottom of the tank. A proportion of the solids (around 30%) will be dealt with by the bacteria in the tank, in an anaerobic (without oxygen) action. The top scum layer is dealt with by bacteria also, but this is an aerobic action, as there is oxygen present at this level. The next action tales place as the waste is passed through a filter bed. This removes more of the toxic particles, and eventually the treated liquid can drain away into the land without causing pollution.
A septic tank takes only a little care to keep it functioning correctly, but it is important to follow some basic guidelines. Firstly, take care not to use too many detergents, as these can upset the balance of the bacteria in the tank, and prevent it from functioning as well as it should. Overuse of bleach is a common cause of problems. Antibiotics can also cause difficulties, as by their nature they eradicate bacteria. Be careful not to flush too much toilet paper or sanitary products down the loo too, as a septic tank simply cannot cope with too many of these solids.
When cleaning the toilet, bath or sink, it is best to use septic tank friendly products, which are clearly marked as such, and are readily available from supermarkets in France. You can also buy one off treatments (activators) to restore good bacteria levels, and it is advisable to use these once or twice a year even if you do not detect any problems.
Your fosse will be inspected by the Mairie every four years, but during this time you should check it regularly and take any necessary action. For example, you need to check the sludge level, and if the tank becomes over 60% full with sludge, it must be emptied and re-started, or partially emptied. It is probably better to partially empty the tank if action is required, as if the tank is completely emptied of solids it will begin to cause a smell unless it is correctly re-started. The water levels and scum layers should also be checked. If a pump out is required, use a registered and approved company (your Mairie will advise) and don't forget you need to retain your receipt to show to the inspector at the four yearly check.
All septic tanks in France are required to be no less than three cubic metres in size (plus one cubic metre for each bedroom over three), but the best advice is to have the largest tank that you can, as this will have more chance of functioning efficiently. Of course, the size and layout of your land is of significance here, and it is important to know that you cannot site a septic tank within three metres of a neighbouring property. It is also forbidden to place a septic tank less than three metres away from trees and shrubs, although smaller garden plants may be exempt from this rule. Despite its name of fosse toutes eaux, rain water must in no circumstances get into the septic tank, so make sure that there is an adequate alternative drainage system for this. Other rules state that you must leave thirty five metres distance between the filter bed of the septic tank and a water source, such as a stream or well. Obviously ventilation is important, and easy access by safely covered manholes is also a must have. It is only necessary to install a fat trap or grease trap if the septic tank is more than ten metres away from the kitchen. If this is called for, try to place it as close to the property as you can.
Whether you are installing a new septic tank or simply wanting to be sure that your existing one is working correctly and in line with the regulations, you can obtain help and advice from your local Mairie. They would prefer that you approach them before you have a problem rather than leave it until the inspection only to find that things have gone badly wrong!
Many people loathe the thought of having to have septic tank in the garden, but if your fosse is working correctly there should be no unpleasant odours and you should not experience any problems. Follow the rules and the guidelines and there is really nothing to worry about.
Additional articles which may be of interest:
Connecting utilities (water, gas, electricity, telephone and sewage) in France
Surveyors in France
Property grants available in France
Life in France
House Renovations in France
Joanna Simm moved to the Languedoc area of south-west France in October 2004 having found her property through French Property Links.
I have a 300m sq garden in France with a well in the middle. I must install a new septic tank but there is not 35m distance from it to do so. Is there any way around this. I have four years to complete the installation. Hope you can help!
Thanks for contacting us about septic tanks. I have been in contact with my colleague in France who says that your Mairie would be the only place to go for help and advice on how you overcome your septic tank issues, so I can only suggest you contact them.
Hi, I was wondering if you could clear somethig up for me. The matter of whether rain water from your guttering can be run off into your fosse septique. Some say yes some say no, can you help as I have no mains drains to take rain water away.
Thanks for contacting us. I would say your Mairie is usually the place to go to get a definitive answer on anything to do with septic tanks.
Lots of sites state that products for septic tanks are clearly marked, but how? With a holiday home in France and limited French I've spent hours looking at labels but not yet seen any form of words or symbol I can recognise. There must be many other people with this problem. Help!
Thanks for contacting us. If you are talking about cleaning products that are septic tank-friendly, I have been in touch with my colleague Joanna who lives in France and who says:
"In my experience, cleaning products which are septic tank-friendly are marked quite clearly, as suitable for use in fosse septiques. In any supermarket of a good size, such as Geant, Intermarche etc, where the loo cleaning products are, you should be able to distinguish them... they usually have FOSSE SEPTIQUES on them very clearly. (As a rule, bleach is bad for fosse septiques.) If you are looking on the internet maybe you could contact the site and say what you want and ask for recommendations? Even in bad French they should be able to make sense of what you want. If you said something as basic as "Je cherche les produits qui sont bon pour utliser avec un fosse septique..." - that is pretty rough but should be effective enough! Or you could ask someone in your supermarket this.
The same goes for the activators. I have picked these up off the shelf with no problems, they really are obvious when you see them! I would suggest you buy them in France when you are there."
I hope this information has been of use.
We have just sold our house in Normandy. We had a fosse inspection by SPANC in 2006 and were given a 3 which we were informed was quite good and needed no immediate action. Having dug up the fosse, filterbed, fat-trap and manhole for emptying, cleaning and jet washing, for the new owners by a recognised French artisan, I am now told by the Notaire I have to dig them all up again for SPANC inspections, and this is the norm now for all house sales. Could you please confirm is this is indeed the case and perhaps make a note on your site to this effect for future readers?
Thanks for contacting us. With regard to your SPANC inspections, I understand that a fosse septique must be inspected every four years, so that would mean an inspection would be due this year sometime, depending on when in 2006 you had it done. But I was not aware that this must be done when selling a house.
However as sellers are required to provide asbestos/termite checks and a survey covering such issues as electrical and gas connections and even ecological efficiency (sort of like the HIPs in the UK), I would not be surprised if this was the case.
And as the rules seem to change from year to year and from region to region, I would suggest the best place to get a definitive answer would be your Mairie.
I am sorry I cannot be of more help.
I have recently renovated a house in France and had a new fosse septique installed. It has been certified by SPANC as conforming with reservation because it is close to neighbouring trees and less than 3m from our boundary. Do you think this will cause a problem when we come to sell the house?
Thanks for contacting us. If this fosse septique is new, then whoever put it in must have conformed to rules and regulations. And if you have the correct paperwork and certifications too, then in theory this shouldn't be a problem when you come to sell. But buyers will be buyers so I'm not sure anyone can definitively say there will be no problem. Anything that does not conform exactly to what is a legal requirement may present issues, but hopefully in your case this will not happen.
We have just been looking at your helpful site regarding the fosse septique in France. Our problem is, we have a fosse septique but cannot find it. We purchased the house three years ago and were told where the tank was, unfortunately it is not where the vendors said it was. How can we find it?
Thanks for contacting us. I think your best option, if you can't get any further information from the vendors (I appreciate you've had the property for a few years), is to contact your Mairie as they should have been inspecting your fosse septique every four years and someone who has inspected it may remember where it is. If not, they should at least be able to give you some idea of where to look for it, as they decide the rules and regulations of where septic tanks should be placed. Then you might have to start digging!
Otherwise you could try asking your neighbours who are often a great source of information. Unfortunately with older properties (though I'm not sure how old your property is), sometimes they are very hard to find, buried deep down with no visible manhole covers, as seems to be the case here.
I wish you all the best in finding it.
This property mentioned below was sold in Dec 2009, are we liable for the cost? In the UK it's up to the purchaser to complete a survey to establish the property's state before purchase. Thus once sold, if say a wall falls down, the seller/vendor is not responsible.
Email from Notaire: I received the papers and I sent them to the Impôts in Fontenay le Comte with the taxes of "droits de succession". I received a call from the buyers of the house in Saint Juire, they are very disappointed because they have many works to do with the septic tank (about 10.000 Euros).
The diagnostic was wrong, SPANC (who did the diagnostic) explained to them that they are not responsible because they cannot get any information from the vendor, or the information from her was wrong. They could not do the control correctly, only if they destroy all the garden.
So the vendors are thinking about an action in Justice. I ask you if you agree to do something, for example, to pay approximately half of the fees, with the guarantee they don't do any action again the vendor (or the inheritance).
Thanks for contacting us. I think you are correct in what you say, in that the vendor of the mentioned property would not be responsible for the costs of the septic tank, as long as correct information was given to SPANC when they came to do their survey. If SPANC was mislead however, then perhaps the vendor would be obliged to help with costs.
Assuming correct information was passed on, then if the survey was incomplete or not very forthcoming with detail, it would have been up to the purchaser to delve more deeply and find out more about the septic tank issues. (And I would think they would have to pursue re-imbursement from SPANC if the report was incorrect.)
However, as I am no expert in these matters, you may like to contact a legal advisor, perhaps using the following page on our site:
We have a property in a small domaine in the South of France which had a septic tank that was leaking sewage into the road. At great expense to all the owners we have had a new drain system put in. The sewage leak has stopped. The septic tank is still there and I was wondering what is the law about disused tanks. Can it be left where it is with no further action or does it have to be removed ?
Thanks for contacting us. I am not aware that disused septic tanks have to be removed, and have heard of people using these as extra water tanks once no longer in use as septic tanks. However, it is the Mairie and Maire who decide what has to be done if anything or what is possible, so I would suggest contacting them.
Hello Jo - we bought a terraced village house in the south of France eight years ago and have just discovered that we have a septic tank in our small couryard garden, which services one toilet at the back of the house (which we never use). We are connected to the mains for our bathrooms, kitchen and other toilet. This information was never disclosed to us during our purchase - do we have any redress as we will now have the unfortunate and expensive task of trying to get someone to take the unused septic tank away.
Thanks for contacting us. In the first instance I would see the Mairie, as they are the ones who deal with all issues with septic tanks, and they may be able to suggest a course of action for you to take.
Otherwise, you could always try to contact the person you bought your house from and the notaire involved in the sale, to see if they will help with the costs involved in removing the tank. If this was not disclosed at the time of sale, then there may be costs you could pursue here, though after eight years this may not be easy.
But does the tank have to be removed? Could it not just be emptied and left in situ?
Hello - I am wondering if you can help me locate septic tank specialists in the Alpes-Maritime area who are qualified/certified to replace an existing septic tank which although working (and is not polluting), does not conform to the new standards. Also, do you know if in fact it is a requirement to replace an established septic tank that is too small for the property but working effectively? Thank you.
Thanks for contacting us. I would suggest you get in touch with your Mairie who should be able to advise you on finding septic tank specialists. Pages Jaunes, forums such as "Total France" and local papers may also provide you with names of companies. Or perhaps ask your neighbours who they use?
The Mairie will also be able to advise what is legal and what is not with regard to the size of the septic tank, as they deal with all inspections and issues to do with septic tanks.
Hi - I read with interest your page on fosses septiques and would like to know just how much of the filter bed we should dig up for an inspection. We have located one corner of it with a concrete inspection trap - do we have to locate all four corners?
Thanks for contacting us. I would suggest you contact your Mairie for accurate information on septic tank inspections in your area and what exactly is needed. The Mairie is in charge of the legal requirements regarding septic tanks, and they carry out the inspections.
Do you know where I can find information, written in English, on how to obtain a grant for installing a septic tank? Our house was built in the 17th century and has no sanitation other than a cesspit. Is there a list of installers in the Creuse or Haute- Vienne available? How much should a 2000 litre tank cost to have installed? Any help and advice would be greatly appreciated.
Thanks for contacting us. I would suggest you contact your Mairie, as it governs all things to do with septic tanks in France. You should be able to receive advice from your Mairie on recommended installers, costs and grants available.
A visitor to the site has kindly reminded us that the minimum size that a septic tank can now be in France is 3000 litres, plus 1000 litres for each bedroom over three.
Our septic tank has been condemned by Spanc. We were told there were grants of 60% towards renewing. How do we find out about this? Our house is in the Pas de Calais.
Thanks for contacting us. Our article "Property grants available in France" (http://www.frenchpropertylinks.com/essential/property-grants-france.html) should answer your question, but the first port of call I would think should be your Mairie.
Where are the filter bags bought from for fosse chamber? Thanks.
Thanks for contacting us. I would suggest you ask your Mairie about this, as they deal with all things to do with septic tanks and should know where to go for these. Though should any visitor to this site know more about this, please do get in touch.
We have been told by SPANC that our septic tank filter is undersized. A local builder installed the tank when he built the chalet in 2000 but confirmed that nobody from the municipality inspected the installation and he has no documents to show it was a formally approved installation. He does though "state" that our installation along with other properties and systems in the area, he constructed, conformed to regulations at the time. It would appear that our Mairie did not inspect and approve any installations as they did not have anyone available or suitably qualified to do it. Additionally the Mairie has made no checks on our installation from 2000 - SPANC is the first inspection we have had in eleven years. Who is liable for any work/cost to upgrade the filter?
Thanks for contacting us. I have not come across this situation before, so can only suggest you sort this out with your Mairie. I would have thought that as they are supposed to sort out inspections of septic tanks and didn't, they may be held partly responsible. Otherwise I think it would be down to the owners of the property. I am sorry not to be of much help.
Does a toilet serving a fosse septique need a flue as well as a sink pipe and if so what size can this be?
Thanks for contacting us. I would suggest you contact a plumber for help on this, or you could check with one of the builders listed on our site, as to their thoughts (sorry, we don't currently have plumbers listed). You can find a list of builders in our Business Directory.
We bought our property approx five years ago, totally in the dark about septic tanks or fosses. We do not know where it is, if we have Fosse or septic tank, no signs of access covers etc. Nothing was said at time of purchase regarding location, certificates for proof of cleaning, no contact at any point from Mairie and nothing from our Notaire!! We are going to contact the old owner to locate the access (which presumably there must be somewhere). My main concern is if there any problems with it, is it our problem as we didn't ask the relevant questions, or is the onus on the seller, Mairie, Notaire for not carrying out the relevant enquries at the time of purchase?
Thanks for contacting us. I would think it should have been an issue for all parties concerned, when you purchased your property. The seller of your property should have given details of your septic tank, with documentation of past inspections. Your Notaire should have made sure all was in order, and you the buyer should have made sure you were happy with the information provided. As the Mairie certainly is the place to go for any issue that comes up with septic tanks, it may be worth having words with them, but as this is only coming to light now, it may, I'm afraid, be up to you to sort it out and absorb any costs.
However, as I am no expert in these matters, you may wish to contact a legal advisor, perhaps using the following page on our site:
We want to build a small wooden house (one bed) now, and a larger stone house (three bed) in a year or so. Under the new regulations, what size Fosse do you think the builders should specify? I know that prices of tanks seem to increase exponentially, so if I need a 5000lt tank, could I use 2 x 3000lt and should I remove the baffle in the first tank?
Thanks for contacting us, though I would check with your Mairie on these issues, as they should know all about septic tanks.
My commune is installing a collective sewage treatment system, and is encouraging me to connect to it. I am a pensioner and owner of my property. Can I get any assistance with the cost of connecting to the new sewage disposal system?
Thanks for contacting us, though I'm afraid I don't know the answer to your question. I would suggest you contact your Mairie who should be able to help you with this.
Bonjour - our new neighbour has bought a derelict house adjacent to our property and is the process of installing a fosse septique. The tank is about 3m50 - 4m from our boundary and a further 3m50 from our pool. It is a very rural area with only four houses and he has 1ha of land. However, he has chosen to put in the tank close to us. I understand that the "drainage" is by at least three parallel perforated pipes leading from the tank. This might mean that some of these are even closer to our property. In the summer months we have dry periods of several months. Last year being a classic example of three months. What are the legal requirements for positioning of these tanks and drains? The new neighbour is a pal of M. le Maire!
Thanks for contacting us. Though I'm afraid the person you need to speak to about this is le Maire, or at least people at your Mairie. They know all about the rules and regulations for septic tanks. However, I was under the impression, as it says in our article, that 3 metres is minimum distance from a septic tank to a neighbouring property and shrubs and trees. So your new neighbour may well be within his rights to install his septic tank where you say. If the location is really not to your liking, perhaps it might be worth having an informal chat with him if you haven't already, to express your concerns and see if he could move it elsewhere?
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