help! Fosse not working properly

[Jhc]

Does anyone have any idea what might be wrong here - I thought Fosses were a great idea and v efficient.  We had to have a sand filter bed installed along with a new grease trap - but the chap from the Mairie  Assainissement dept that came to advise on what was needed said we did not need a new septic tank, just to have the old one emptied, which we did in May 2005.  He then re-visited after sand filter and grease trap was installed and gave us a Cert of Conformity.

However, all last summer we noticed a build up of liquid in the Inspection chamber situated at the far end of the sand filter pipes - we know that this was really supposed to remain empty as the water /waste is supposed to drain away through the sand filter before reaching there.

To our horror we now find that the chamber is repeatedly filling with water and what look like brown sludgy lumps (like partially treated sewage!). ( Fortunatley it does not smell particularly unpleasant so it must have undergone some decomposition.) However, how can this be so, as the liquid that leaves the septic tank should be a completely clear fluid - shouldn't it????  There are only the 2 of us using that septic tank so it's not overloaded.

If anyone has any ideas then please pass them on.  Thanks in advance. 

[Alcazar]

You HAVE put "Eparcyl" down the loo, haven't you?

From what you've said. it sounds as if the tank you have isn't big enough. Is the fosse now tous eaux? (All water into it?) If so, it needs a tank of at least 3000 litres, IIRC.

I'd be inclined to get a specialist to have a look before the sand filter needs replaced too[:(] Ask at the Mairie who to contact.

Alcazar

[maude]

It sounds like a very similar problem to ours.
Maybe the water table is too high to allow the sand filter bed to drain.I  dug a 50mm diam hole in my garden yesterday,and hit water about 500mm down.I then filled the hole with water,which then sat there for 4 hours before draining down to the first water level .Obviously we have a general drainage problem on our land.There is also an underground spring in one part which makes the grass grow over this area troup vite!My dowsing rods also go berserk over this part!Havent decided what to do yet,as I dont want to raise a hornets nest by enquiring at the mairies! Maude.

[Jhc]

Thanks - it's had regular Eparcyl and some extra.  It's not tous eaux - the Marie Assainisement chap is supposed to be knowledgeable about Septic tanks as in our area it's his full time job to advise all households what needs doing to bring their systems in line with current regs and then provide a Cert of Conformity.  He said ours was not big enough for tous eaux but we could keep it as long as we has a grease trap put in for the remaining grey water.  It's a mystery!

[Clair]

The far chamber is there as a final check that the filter is doing its

job.

In ideal conditions, it stays dry and should only get wet if the

soil gets soaked through with massive amounts of rainwater and is therefore

unable to cope with the filter + the rainwater.

If the last chamber is wet, it means the filter is not working. It points to the filter pipes being blocked.

If it also contains solids, it means the fosse is not working. Solids should not get into the pipes so it might be that the septic tank itself is blocked and overflowing. The tanks could overflow if it is cracked and allowing rain water to seep in for instance...

Whatever it is, you will need to dig and check urgently.

[Dave&Olive]

[quote user="Clair"]The far chamber is there as a final check that the filter is doing its job.
In ideal conditions, it stays dry and should only get wet if the soil gets soaked through with massive amounts of rainwater and is therefore unable to cope with the filter + the rainwater.
If the last chamber is wet, it means the filter is not working. It points to the filter pipes being blocked.
If it also contains solids, it means the fosse is not working. Solids should not get into the pipes so it might be that the septic tank itself is blocked and overflowing. The tanks could overflow if it is cracked and allowing rain water to seep in for instance...

Whatever it is, you will need to dig and check urgently.[/quote]

    hi

        this last post is a load of cr@p .

      quote    The far chamber is there as a final check that the filter is doing its job.

this is correct......
In ideal conditions, it stays dry and should only get wet if the soil gets soaked through with massive amounts of rainwater and is therefore unable to cope with the filter + the rainwater.

wrong

      the far chamber or reguard should always be wet ... ie  a the water into the tank should flow out clean through this outlet via the filter...    and wrong    no rain water should be going into the fosse or the sand filter..

so ok  a question  ..      is the land ie soil level dropping down over the filter bed , and does the outlet from the filter bed ever become covered in water????

                        dave

[Jhc]

Dave - thanks - I am not sure I entirely understand your question but will explain best I can.  There is a 3 foot drop down from the road to the sand filter bed, then a horizontal terrace on which the filter bed sits, then the land drops away v steeply with about a 9 foot almost vertical drop down to some more gently sloping land.   The outlet from the filter bed has not become covered in water - but  I keep emptying the end chamber. I am beginning to think it is a filter bed problem and not a septic tank problem.  Fortunately the septic tank is v accessible as it sits in a concrete terrace and I can remove a cover and see it.  I know it's big enough for 6 people and there are only 2 of us.  I can see its not cracked or anything untoward.  Since my first post I have had some fine wire netting placed in the manhole where the septic tank effluent joins up with the grey water from the grease trap, prior to them both flowing into the sand filter.  I am sure the netting would have caught any untoward solids - and it's entirely clear.  Could colour/particles/chemicals be leaching out of the sand filter because of all the rain we've had and therefore waterlogging of the filter?  Perhaps it's not septic tank semi -solids that I am seeing but a sludgy sandy mixture that is coagulating together!  Thanks for any suggestions

[Clair]

Hi Dave

I feel have to reply specifically, as you have taken my post to task...

The last  chamber in MY set-up is meant to work as a final check: it is situated after the sand filter and before an overflow pipe and acts exactly as I have described. This is the one I have described above.

The chamber situated between the fosse and the filter works as you described (clear liquid into the filter) but it is not the last chamber.

I agree with you that no water should be going into the fosse or the filter.

I'm basing my reply on the work done at my house as recommended and certified by our local SATESE. It is a fact that different types of soil require different set-ups... It may be we're posting at cross purposes here...

[Robbos]

Please can I ask another related question.

 

What is Eparcyl and where can I get it and how do we use it?  We are moving into our new home in 4 weeks and it has a fosse.  Previously it was used only as an occasional holiday home.  We had the fosse checked when we bought and it is in good working order, although we will probably have to replace next year as we plan an extension.

 

However this summer people plan to visit and we will use it daily so quite an increase in activity for the poor thing.  I want to be sure we use the right stuff to keep it digesting properly so all advice gratefully received.

 

Also which detergent should I use if our washing machine water goes into it, not sure but I think it might do.

 

xx K

[Jhc]

Eparcyl is a powder available in sachets in a biggish box - available in most supermarkets (near the loo cleaners etc,) and in most hardware stores.  You put a sachet into the loo about once a week - instructions as per number of people are on the packet. Any loo cleaner /disinfectant you use should have 'sans danger pour la fosse septique' written on it.  I think washing detergent is OK as long as it is without bleach.

[Dave&Olive]

hi

  clair first

      ok first the quote " cr@p " was meant to be be a bit of a pun so no offence meant or taken. If you have an overflow on your system , I  do not think  you have a sand filter system but a piped system ,this is for well drained soil, but would have to inspect to be sure.

now back to the problem    best first ,,  the out let pipe from the sand filter is blocked or is now sloping up hill , this could be caused by a bit of subsidence with the wet weather we have had.

        second you have clay soil and the filter has not been fitted in a bag , this again the wet weather causing clay to seap into the filter..

       third and worst case the geo-tex  or geo - grille layer between the sand and bottom layer of gravel has split and the filter bed ( the sand ) is running through the outlet.

              dave

oh and ps

       your grease trap should run into the fosse not the filter bed

[Jhc]

Dave - thanks very much for those ideas - it has given me a lot to think about / explore but I will wait until the whole area is a bit dryer.  The grease trap water definitely does not go into the fosse - it was deemed too small to take that water - we were told it would be fine to have the grease trap water joining up with the effluent from the fosse and both going into the sand filter.  We got our Cert of Conformity on that basis. We had a local artisan fit the whole thing - he seems to do all the fosse/grease trap/sand filter installation around here.

[Clair]

I remembered this morning about 2 very good publications about septic tanks...

I got them from the Centre for Alternative Technology (CAT)

They are:

• Country Plumbing - Living with a septic system by Gerry Hartigan (designing a system and having it built - Understanding maintenance requirements - dealing with emergencies) - ISBN 0-911469-02-8 £8.95 in 2003
• Septic Tanks: an overview (2nd edition), by Nick Grant & Mark Moodie - ISBN 0-9526957-1-5 £5 in 2003

And if you've never looked at CAT's website, you really need to as it's full of tips, ideas and suggestions, all very useful when living in rural France...

[Jhc]

Thanks Clair - that's a really good idea - I will order one right away.