Possible dodgy fosse - what to do next?

[Nearly Retired (I am now)]

On the penultimate day of our last stay in France the boss flushed the loo 6 times in quick succession and the final flush did not leave the pan properly - the water level took maybe half an hour to drop to normal. The basin trap did a lot of gurgling at the time too. Taking it carefully from then on and leaving long gaps between flushes the problem did not re-occur but it seemed that the water level in the pan was taking maybe just a moment longer to drop than normally.

At first I thought that we might have just overloaded the poor thing. We thought about a possible blockage, but a day or two before this we twice noted (after each flush) a smell from the high level internal air admittance valve.

We've had the house 4 years and an average of 2 people have occupied the building for maybe a total of 30 weeks. We are very careful about what goes down the loo and always give the fosse a bacteria bag or two at the start of each visit.

I guess it was installed in the mid-1980s and I have no idea when the fosse last received any TLC and I'm certain it's not a super up-to-date one - I can't see any grease trap or manhole. All that can be seen in the garden close to the house are two markers set maybe 3m or 4m apart in a direct stright line with the toilet location in the house. A couple of years ago I peeked under the downstream lid, removed a few weed roots and noted a clear liquid dribbling along. I presumed I had found the fosse! (or a pit?).

We had no time to investigate before we left this time and I guess we could manage to use it for a few days when we go back, but all is does not seem right and we may need someone to take a look.

Any ideas please from those in the know? 

[Pierre ZFP]

Sounds exactly like the trouble I had in June this year.  To confirm if the fosse is full (assuming you don't have direct access to it) put a dip stick down the vent pipe to determine the level.

I removed what I thought was the cover of the fosse to find it was the cover to the soakaway.  Thoroughly confused, I visited my brilliant plumber who sent out a chap that afternoon. To cut long (and messy) story short, after much digging we found the top of the fosse and after a struggle, got the cap off.  It was full, not another,  thing, could possibly get in it.  A couple of phonecalls later, the chap from the Plumber gave me the address  of the local 'effluent remover', well, farmer to tell the truth.  It was close by so I paid him a visit (good job he was in).  He came immediately to take  a look and yup, it needed emptying, no problem but no access for his machine either!  Off to the neighbour to see if it was OK to use his drive and sling the hose over my hedge, yes of course. A bit later the farmer returns with a tractor the size of my house (no kidding) towing a tank which had a plate on it saying the capacity was 50 000 litres!! A few minutes to fix up hoses, fire up the tractor and create a vaccum in the tank and we were ready.  He's just about to turn the lever when he warns that the removal of the waste could cause the fosse to collapse!  Well I have no choice so I say go for it!  Literally 15 seconds later, 4000 litres of finest waste is in his tank, after which I'm sure it will go into his slurry pit and at some date enrich a part of his fields.

After this, the fosse did not collapse but neither did anythig flow from the loo!  Farmer fetches his big plunger (much bigger than my little thing) and after several minutes of vigorous pumping and plunging, all was released!!

A sum of money changed hands (PM me if you want to know how much) and harmony was restored!

I should point out that while this was going on, half the village invited themselves round to inspect the fosse (nothing much happens in my village). Much hand-shaking and introductions and every one saying 'I wouldn't have put the fosse there, should've put it over there, why didn't you?' By the end of the afternoon I wanted to shout 'Look, I didn't put it there, that's where it was when I bought the house'

Still, apart from now having a working loo which is a great relief, I seemed to have 'arrived' in the village and have since been given such things milk, straight from the cow, a brace of rabbits and I have found that a near neighbour is an importer of wine from Bordeaux and sells it 'en vrac'. In return I give my excess geraniums and other plants so all in all, a very happy ending.

[Nearly Retired (I am now)]

Thanks for the info Pierre ZFP - anybody else had this issue?