It is currently Wed Jul 26, 2017 1:38 pm

All times are UTC + 1 hour





Post new topic Reply to topic  [ 34 posts ] 
  Print view Previous topic | Next topic 
Author Message
 Post subject: House drainage, Fosse septiques and mains drainage
PostPosted: Wed Dec 01, 2010 8:34 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
Most problems with waste water plumbing are caused by not obeying a few simple rules. To help you understand the rules, I will describe a few common problems their cause and how to cure them.

But first a few technical names and what they mean , without being too technical

Fall - this is the slope of the pipe work, allowing gravity to assist in the drainage of the property, be it rain water, foul water, or grey water (water from a bath, wash hand basin, shower)

Back Fall - This is where the fall in the drainage system is going the wrong way, the outlet is higher than the inlet

Drain - Any drainage pipe laid horizontally in the ground: Foul Drain, the pipe which carries human waste; Rain Water Drain, as the word says a pipe carrying rain water

Soil and Vent Pipe - (for shortness SVP) the vertical portion of the foul drain, it becomes a vent pipe after the highest appliance connected to the SVP, and serves to ventilate the drainage system

Vent Pipe, or Vent Shaft, Vent Stack - A pipe with no appliances connected to it, normally serves to ventilate either the main sewer, drainage system, or the septic tank / drainage field

Waste Pipe - Any pipe connected to a domestic appliance other than the W/C, which serves to allow the used water to drain away, normally this is connected to the SVP, but can be found connected to the rain water pipe (not to be recommended)

Plug of water or Solid plug of water - This phenomena is caused by the waste pipe running full bore before the water flattens out owing to the surface tension on the pipe walls etc. This effect is normally only for a few centimetres length of pipe directly after the trap, but can influence traps on the same waste, a w/c flush when it is a short branch before the SVP forms a solid plug of water in the first metre or so of vertical pipe, before the friction of the pipe wall retards the water close to the pipe wall and the centre of the plug of water falling faster than the water closest to the pipe wall opens and the plug of water is more like a sleeve of water running down the pipe wall, this plug of water can blow out the trap seals unless the pipe is ventilated

Loss of Trap Seal - (this can be caused by induced siphoning, self siphoning, or in very rare circumstances the water in the trap can be blown out)

Automatic Air Admittance Valves - (commonly known either has a 'Durgo valve' or AAVs)

Spill over level - This is the level at which water overflows the appliance; A A V's should be fitted 15 cm above the highest appliance on that part of the drainage system spillover level

Head of Drain Vent / SVP - This is the furthest part of the drain away from the sewer connection or the septic tank connection, this helps to ventilate the drainage system

Sweep Tees or Swept Tee - A 'Tee' with the branch sweeping in the direction of flow, normally called a swept tee on sizes below 75mm pipe work, above 75mm pipe normally called a branch

Cross or double branch /Tee - This is similar to a 'Tee' but has another branch opposite

Corner Branch - This is a branch with another branch at right angles to the other branch, and can be either on the left or right hand side

Reducing Fittings - These allow a smaller pipe to be connected to a larger pipe or fitting, and can be in the form of a cap / plug, or an eccentric tapered fitting

Stub Stack - A short length of unventilated pipe coming off a ventilated drain, normally serving an isolated ground floor w/c with a wash hand basin

Opposed or Opposite connections - Connections facing each other on a SVP

Ventilating pipe or Ventilating loop - A pipe running off the waste pipe in an upward direction and connecting to either a ventilating pipe connecting sanitary appliances on various floors to the ventilating portion of the SVP, or if on one floor only, back to the SVP above the highest appliance; this pipe is to equal the pressure in the waste pipe both before the water and after the water being discharged
(The diameter of a vent pipe can be one pipe diameter less than the waste pipe, normally 32mm is the smallest size used, with a 50mm vent from a w/c (this should not concern a normal domestic plumbing situation) and a 50mm main ventilating pipe which connects back to the main SVP above the highest appliance

Strap on, or Saddle boss Connections - these are used to make a connection to an existing SVP, and they are an abomination to my mind, because they are prone to leak unless fitted with the utmost care, it is far better in my mind, unless there is a problem with the height of the connection, is to cut out a section of pipe work fit a branch with a repair socket (manchon a coulisse, in French) this is a male solvent joint (on the bottom) with a female double length rubber ring joint socket (on the top),the repair socket is slid up the SVP , after measuring the required distance to be cut out of the SVP , the branch is fitted into the SVP , then the bottom spigot of the repair coupling is coated with solvent cement then slid down the into the socket of the branch, already fitted to the pipe work
Another even more disgusting abomination are the 'new on the market' flexible 'tees' and straight connectors, because the cheap versions are corrugated there is a tendency for filth to be caught in the corrugations and eventually causing blockage, these should be avoided at all costs

Bends and branches start at 22.5 degrees, then 45 degrees, 67.5 degrees, 87.5 degrees, a sector is a small socket / spigot 15 degree bend, corner branches can also be found these are a branch with the same size branch at 90° to the other branch and are handy for connecting two soil runs from two bathrooms etc at 90° to each other, also crosses can be obtained these are suitable for connecting two bathrooms to the same SVP, but the branches should be ventilated to avoid trap seal loss


Different types of Mains Drainage; Under local Authority Control

This does not include Drainage to a Septic Tank (See notes at the bottom)

Separate System - Two sets of drains, one for the foul water, this drain runs to the authorities sewer and then to a sewerage disposal plant; the other one is for rain water this runs to a water course

Combined System - both foul water and rain water runs to a sewerage disposal plant, and in times of heavy rain fall can overload both the sewers and the disposal plant

Partially combined system -; part of the rain water can be connected to the sewers the idea of this is that in time of heavy rain fall, an overloaded rain water drain can discharge a 'flush' of rain water down the foul sewer to flush out any debris left on the sewer invert in dry flow conditions



Part 1

The ideal system of drainage

If the fall on a pipe is too great there is a risk of solids being left behind by the flush of water, conversely if the fall is too shallow the solids will drop out of suspension, both situations can lead to blockages

The Ideal fall is between 1cm and 2cm a metre run, in other words if the length of the drain / waste pipe, is 5 metres between the start of the pipe and the finish of the pipe, there should be a difference of between 5cm and 10cm measured vertically between the start and finish of the pipe

Soil pipe is normally 100mm in diameter, but can be larger depending on how many appliances are connected to it, sometimes it can be found in either 80mm or 75mm in old properties

Waste pipe sizes normally 32mm diameter for wash hand basins or bidets
40mm diameter for sinks, baths and showers
But there are exceptions to the rules depending on how many appliances are connected together, a 'trunk waste' can be 50mm, 63mm in diameter, if a wash hand basin waste has a vertical drop from the basin trap, to the horizontal waste pipe, to avoid self siphoning the waste size should be increased by one size


Loss of Trap Seal
Induced Siphoning, this is caused by a solid 'plug' of water falling down the SVP and has it passes the waste pipe connection causes a partial vacuum which draws the water out of the trap, the most likely cause of this partial vacuum is that the SVP is only a soil pipe and there is no opening to free air
Self siphoning, the waste pipe fills with water and creates a partial vacuum behind the water pulling the water out of the trap behind it (this is not too much of a problem with a bath or even a sink because there is always a tail of water to refill the trap, but because a wash hand basin is more funnel shaped there is not so much water to drain and refill the trap)
Blown Trap, a plug of water falling compresses the air in front of it, this compressed air can force the water in the trap to be blown out of the trap

AAVs, these can form part of the system, but they do not replace the need to ventilate the system, by means of a proper sized SVP, the AAV should terminate 15cm above the spill over level of the highest appliance, and be fitted internally, to avoid condensation freezing on the membrane thus stopping the membrane from allowing air to pass into the pipe work
Spill over level, used in conjunction with AAV, this is the height of the highest appliance connected to the waste pipe / soil pipe, at which the water contained in the appliance spills over the appliance


Part 2

How to check for problems with an existing drainage system

Have a look at the pipe work if its outside the building, is the SVP 100mm? Does it run all the way up the building and above the top most open window by at least 1 metre or 3 metres away in a horizontal direction? Any changes of direction, in the decent of the SVP, on the same wall, are they almost 90 degrees (actually 87.5 degrees) right angle bends, if so good, 45 degrees bends not so good, no vent pipe or a short piece of pipe of what ever diameter, bad point

Fill each wash hand basin in turn then let the water go, bubbling sound from any other appliance, bad point, gurgling sound from wash hand basin after water has left the basin or from any other appliance, bad point, do the same with the bath/s, and any other appliance, the same notation applies as above

Flush the WCs. Any gurgling/bubbling sound from other appliances or if the water in the w/c pan rises in the pan before running away, same if the water seal in the w/c pan trap is lower than 50mm, after flushing bad point

Fill all appliances to the overflow point then let them all go at once any slowness to run away, 'backing up' strange sounds loss of trap seal (put a wire down the waste to the bottom of the trap and measure the water on the wire it should be about 50mm to 45mm, if so a good point if not a bad point

General observations; any marks of leaking pipe work, drips of water from joints, does the pipe reduce in diameter going towards the sewer or septic tank, any AAV’s fitted on the outside pipe work, bad point

When the pipe changes direction from the vertical and becomes the drain this bend should be a large radius bend to ease the flow of water, if the bend is too 'tight' the water can form wave and curl back on its self causing turbulence and over pressure in the pipe work leading to trap seal loss


Faulty trap seals
Or traps where the water seal has evaporated. (I have even seen the trap seal in a w/c reduced to 10mm water seal under the influence of wind blowing over the top of the SVP ). Can lead to drain smells and even if not noticeable to the nose can cause a general feeling of being unwell, which can be hard to trace



Part 3

How to design a simple house drainage system

The best idea is 'K I S S H L' - Keep It Simple Saves Hassle Later

If you can, have one SVP for every thing up to two bathrooms adjacent to each other, with the kitchen below the bathroom

If there has to be bathrooms at the opposite ends of the property make the one the furthermost away from the drain the main SVP, the other soil pipe can either have a reduced ventilation pipe or an AAVs fitted 15 cm above the highest appliance spill over level, to save on pipe work

Wash hand basins are the most difficult to fit, to avoid problems of siphoning, because of their shape, being 'funnel' shaped this encourages the water to run out in one solid piece of water, without leaving a 'tail' of water behind like in a bath to refill the trap, the maximum recommended length of a wash hand basin, waste pipe 32mm diameter with a fall of 10mm / metre is only 1.5 metres, the length can be increased to 3 metres if the waste pipe is increased to 40mm , and you will only get another meter length if the waste pipe is increased to 50mm diameter

It would be far better in my opinion, if either an AAVs is fitted or a "loop vent" is fitted, this can be in 32 mm pipe work, connected within a maximum distance from the trap on the appliance of 750mm connecting to a 50mm ventilating pipe connected at the bottom of the SVP where it connects to the drain and connecting back to the main SVP above the spill over level of any fitting on the highest floor, this form of loop venting could be connected to all the appliances on each floor with the proviso, that the ventilating loop on each floor must be above the spill over level of the highest appliance on that floor

The maximum length for a w/c branch connection is 15 metres, between the centre line of the w/c and the SVP , the recommended fall is 20mm / metre

The bend connecting the SVP to the drain should have a minimum radius of 200mm, and the correct angle of the bend is 87.5 degrees to allow for the fall in the drain

A distance of 450mm between the invert (the inside bottom of the drain, (the soffit is the inside top of the drain)) and the lowermost connection to the SVP , must be respected if siphoning problems are to be avoided

A 'Stub Stack'
Consists of a short length of 100mm pipe connected to a ventilated drain, can be used to connect a w/c, or other appliances, to a ventilated drain, without the need for a ventilating pipe, providing the following conditions are meet; the maximum depth to the invert of the bend connecting the stub stack to a ventilated drain is no more than 1.5 metres from floor level, and the highest appliance connecting to the stub stack is less than 2 metres above the invert of the bend connecting the stub stack to a ventilated drain

Opposite connections on a SVP ,
These are branch connections on the same plane but 180° apart, there is a risk that water from one branch will 'jump' the gap and run up the other branch, especially a w/c on one side and a bath waste on the other side, to avoid this a "Zone of Prohibition" is drawn around the w/c connection to the SVP this extends from an angle of 90° to 270° drawn from the centre line of the connection extending downwards for 200mm, in this "Zone of Protection" no other connection should be allowed, in this area

Offsets

There should not be any changes of direction from the vertical, in the wet part of the SVP other than where it turns into the drain, if change of direction is unavoidable no appliances should be connected within 75cms of the offset / bends forming the offset

The lowest connection to a should be NOT LESS THAN 45cm above the invert of the drain

Access points should be allowed for cleaning, normally these can take the form of a sweep tee in place of a bend, with a cap on the end of the upper end of the tee



Part 4

Drainage, Below Ground

Changes of direction and connections to a drain
In drains a change of direction should be has large as possible, connections to a drain these should be by way of a 45° branch and a 45° bend if the connection is at right angels or is parallel to the main drain, at all times it is advisable for the branch drain to connect to the main drain by way of a 45 degree branch instead of a 87.5 degree branch, so as to sweep the water in the direction of the flow

Manholes
If the drain has a change of direction a manhole should be built on the change of direction, a manhole should be built where a branch drain connects to the main drain, and also on very long runs of drain in excess of 30 metres in length manholes should be built every 30 metres with a manhole within a metre of the SVP connecting to the drain

Because in France there are no forms of access to rod a blockage, like the access doors and branches and bends with access doors available for soil pipe in the UK, I would advise, where a 100mm branch is coming off the main drainage run, to serve a sink etc on the ground floor, instead of using just a 100mm bend with a reducer, fit a 100mm branch with a reducer in the branch a 100mm M x F 87.5 degrees bend into the run (or top) on the branch fitting with an access cap at finished floor level, so that the branch could be roded in case of blockage, also instead of a 87.5 degrees bend at the foot of the SVP an 87.5 degrees branch could be fitted instead with either the pipe extending through the external wall terminating with a cap or a bend with an access cap finishing at floor level so that the main drain could be roded through, a 'stub stack' serving an isolated w/c, ground floor bathroom, could also have an access cap instead of a cap to serve as a roding point


Septic Tank Drainage
There should be a properly sized system of drainage, for all waste water from the property
The actual design of a septic tank system of drainage is dependant on the local ground conditions, a study should be carried out by the local authorities or an independent body who have knowledge of the area and the local regulations (a grease trap if fitted should be within 2 metres of the property, and only be on the kitchen drainage, the idea of this is to stop any fats etc from coagulating on the inside of the drain before it can be trapped in the grease trap, it should be inspected every month and cleaned if needed, if not it should be cleaned every six months)

Septic tank ventilation
The ventilation of the septic tank and drainage field is by means of another 100mm Vent pipe, running to about the same height as the SVP (this vent pipe can be run parallel with the SVP or in another place on another building), this vent pipe is to ensure a free flow of air through the filter bed (an air inlet is fitted at low level to the far end of the filter bed, extending down to, and connecting to the pipe work in the filter bed), and also to vent off the gases formed by the break down of the sewerage in the septic tank, (by means of a branch connection from the septic tank, to the vent, this connection is fitted at higher level than the inlet to the septic tank, on the septic tank and above the level of the contents in the tank) the direction of flow on the branch should be to the high end of the vent, to allow the gas from the septic tank to flow from the tank to the high end of the vent, and not back to the drain age field, this horizontal section of the vent should have a continuous rise from the drainage field to the foot of the vertical vent pipe


Notes on Fittings, English to French, and other French specialities
PVC 100mm soil pipe = Tubes d'evacuation
Reducing fittings = Tampon de reduction M x F (a concentric reducer), Reduction excentree M x F
Collar or Socket F x F with a stop in the centre = Manchon a butee
Bend F x F or F x M = Coude F x F or F x M a small angle bend is known as a sector
Expansion coupling = Joint de Dilatation
Branch = Tes or Embranchements (these can be F x F x F, or F x F (on the branch) x M), and can be equal sized on all ends or have the branch reduced, a parallel arm branch (cross) and a corner branch (2 branches at right angles) are normally known as embranchements, you would have to specify what angle of branch and if the branch is reduced
Cleaning Eye or Roding Eye = Tampon de Visite
Fixing Clip or Pipe Clip = Collier de Fixation
Termination on the end of the vent pipe = Chapeau de Ventilation
Main drain trap = Siphon Disconnecteur 87°
Non Return Valve = Clapet Anti Retour
Repair coupling = Manchette de Reparation M x F (the male end fits inside the pipe) or Manchon a Coulisse (this is a female end, double socket with a rubber ring joint, the other end is a male solvent weld joint (to go into a coupling)
Saddle Boss = Selle de Branchment
Manholes = Regards, either in concrete (Beton) or PVC, can be obtained in 200mm x 200mm, x 160mm high, 300mm x 300mm, x 290mm high or 400mm x 400mm, x 300mm high usually with a knockout for the pipe to be fitted into the hole
Extensions to the manholes = Rehausse
Covers to the manhole = Couvercle
Septic tank filter bed fittings
grease Trap = Bac Separateur de Graisse
Porous pipe, Perforated pipe = Tube d'Epandage
Manhole at the start of the filter bed = Regard de Repartition
Manhole at the end of the filter bed = Regard de Bouclage d'epandage


Personal experience: An architect specified an AAV to be fitted to a soil pipe on a range of 2 w/c's fitted on the first floor of a school, there was a vertical drop of 4 metres to the drain which was 20 metres in length to the main drain; when the w/c's were flushed the water just 'backed up' in the pans until the AAV was removed, the reason for this was that the air in the drain was cold and wet, and was of sufficient density to hold back the water in the w/c pans, we fitted a 4" vent pipe through the roof (a 2" vent would have been sufficient) to over come the problem

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Feb 24, 2011 12:53 am 
Offline
User avatar

Joined: Tue Apr 07, 2009 12:27 am
Posts: 100
Location: fribourg, suisse
Image :D


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Sep 24, 2015 12:08 pm 
Offline

Joined: Thu Sep 24, 2015 9:35 am
Posts: 1
hello,
we are having problems with our connection to the mains drainage and need impartial professional advice.Who should we contact?
Thanks


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Sep 24, 2015 1:25 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
Could you elaborate a bit more on what the problem is please

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Sep 24, 2015 2:06 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
My god Peake just like going back to tech. college, can't you ever leave it alone and retire? yes I know there's always some who need advise, in my mind first are the French as their way of doing septic tanks in the past was a disaster.
When I build the first here back in 1989 the maire just couldn't believe it and wanted me to take on doing it for the whole of the commune as they were having so much trouble. Well if you build a cesspool instead of a proper septic tank what can you expect and I bet that a lot of people don't know the difference.
I still do double chamber ones and have built triple in the past for a big house with plenty of bathrooms/wcs. doing it like that the drain water is clear so never any sediment in the soakaway drains.
Keep up the good work your a much better man than I, at my age now its only just for me.

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Sep 24, 2015 5:42 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
Well Papi, you know the French, and if it works (just about) why bother in trying to make a better one, especially if it was invented in France :lol:

The invention of the septic tank is credited to Frenchman John Louis Mouras, who, during the 1860s constructed a masonry tank into which was directed various household detritus from a small dwelling in Vesoul, France, subsequently overflowing to an ordinary cesspool. After a dozen years, the tank was opened and found, contrary to all expectations, to be almost free from solids. Subsequent to collaborations with one Abbé Moigno, a priest-c­um-scientist of the period, Mouras was able to patent his invention on 2 September, 1881. It is believed that the septic tank was first introduced to the USA in 1883, to England in 1895 and to South Africa (by the British military) in 1898.

Have a look at the date I posted the first posting, the posting was intended for the general public, as an aide to help them when having sanitation installed in France, not those well versed in the "Black arts" of rural sewage disposal :YMDEVIL:

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Sep 24, 2015 7:14 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
As i said in the first line of my post Peake there's always someone needing advise, and there always will be, very good job that there's people like you to give a helping hand.
Call me selfish if you like but now I'm out of it.

ps must admit didn't see the date of your post on the subject.

Must be a bit spaced out from spending a couple of weeks up in your part of this beautiful country, our first and what a good surprise at how friendly they are, ready to have a joke and take the fool of themselves.
Only trouble was we kept thinking we had taken the wrong turning and landed up in Whales with the road-signs.

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Thu Sep 24, 2015 8:00 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
Papi, I'm beginning to be a bit like you, after all I am only a couple of years, if that behind you, but we have to keep on going, 'cos the youngsters dont know half of what we have forgotten, they dont teach it now at the tech, like in our day, even my eldest, who had a good grounding with me in the UK, picks my brains, now and again on plumbing, but I suppose he has a bit of an excuse, he turned "traitor" and now does electrical, together with heating

I suppose that I was lucky in a way, in the right place at the right time,, and worked for some of the "big boys" for industrial and commercial plumbing, plus a year or so in the drawing office, designing commercial plumbing systems, so had a good all round grounding in the art of plumbing

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Fri Sep 25, 2015 6:52 pm 
Offline
User avatar

Joined: Mon Feb 02, 2009 3:57 pm
Posts: 3373
Location: Sussex and Cantal
Here's one I disastered earlier

Attachment:
fosse.JPG


You do not have the required permissions to view the files attached to this post.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Fri Sep 25, 2015 7:08 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
Dont "knock it", it was my bread and butter once :lol:

I would say, seeing that manhole, it was time to get the rods out and give it a good rodding through, thats if you could stand the smell

Early on in my time in France, when I could not speak the language, I asked a mate of mine to phone for the "honey bee" wagon for me, when the driver arrived he asked where the septic tank was, 'cos he usually could smell them a mile away, we showed him where the tank was, and my mate asked if he could watch, because he had never seen a tank empted before, we both warned him about the smell when the suction pipe broke through the crust, but he said that it would be OK, I have never seen a person go from a normal flesh colour, to a colour green like the deeper green of the forum board, so quickly in my life, gagging and retching, both the driver and my self were falling about laughing looking at my mate and the state he was in =)) :YMDEVIL:

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 1:02 pm 
Offline

Joined: Thu Jan 26, 2012 9:43 pm
Posts: 101
I know this is quite dated but I hope someone can assist me, so I have installed the fosse " tous eau", incidentally I was under the impression that there was some sort of barrier between the two inspection lids, but having looked inside it is just one big chamber. So from the outlet I think I have to place a submersible pump in some sort of chamber so as the "clean" water can be pumped to the filter bed, any idea where I would obtain such a piece of equipment. I replaced a pump in one ages ago for a friend and the chamber for the pump looked like an old blue chemical vat with a screw on lid which had been adapted. Thanks in advance.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 3:36 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
A lot of legislation has been passed since I wrote the above posting, the Service Public d’Assainissement Non Collectif (SPANC), are the people, in your area to contact now, http://www.assainissement-non-collectif.developpement-durable.gouv.fr/mes-droits-et-obligations-en-tant-qu-usager-du-r34.html

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 4:31 pm 
Offline

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 9766
Location: Alpes-Maritimes
I've just had one of the aforementioned installed. Mine is all down to gravity. They put the tank in place created the soak field and all the pipes and stones and stuff. Then filled the tank with water to stabilise it and stop it floating in case of heavy rain. The solids go to the bottom and get digested and the water at the top goes to the soak field via the outlet at the top of the tank. It's 4 cubic meters, so not too much of a beast.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 4:54 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
DaveW wrote:
I've just had one of the aforementioned installed. Mine is all down to gravity. They put the tank in place created the soak field and all the pipes and stones and stuff. Then filled the tank with water to stabilise it and stop it floating in case of heavy rain. The solids go to the bottom and get digested and the water at the top goes to the soak field via the outlet at the top of the tank. It's 4 cubic meters, so not too much of a beast.


Nah it's not like that, the solids come to the top and in time or with a starter ( years ago we used a dead cat) get eaten by bacteria, hence the crust on top as in Peake's earlier post.
Fine particles sink down, a fosse should really be in two chambers with P pipes joining so that only water passes to the second thus out to the drains, most French Fosse's I've seen are just one chamber which is why they get so !much trouble with them.
But what does this aging old codger know, well I have built dozens and dozens of the things both here and back in the UK.

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 6:14 pm 
Offline

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 9766
Location: Alpes-Maritimes
I'm sure you're right I only seen the before and after, I haven't a clue what's inside the tank, other than water and shit. My point was, there was no need for a pump.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 6:35 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 9:02 pm
Posts: 11407
Location: 24, Jumilhac-le-Grand
There's a tongue in cheek publication called "101 things to do with a dead cat", and putting one in a septic tank as the bacteria instigator was not one of them! :lol:

_________________
"What is this life if, full of care,
We have no time to stand and stare."
W H Davies


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 6:43 pm 
Offline

Joined: Fri Sep 16, 2016 6:00 pm
Posts: 104
Bayleaf wrote:
There's a tongue in cheek publication called "101 things to do with a dead cat", and putting one in a septic tank as the bacteria instigator was not one of them! :lol:


I liked the pencil sharpener one.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Sun Jul 09, 2017 6:43 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
Bayleaf wrote:
There's a tongue in cheek publication called "101 things to do with a dead cat", and putting one in a septic tank as the bacteria instigator was not one of them! :lol:

Much cheaper than the chemical alternative.

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 10, 2017 11:28 am 
Offline

Joined: Thu Jan 26, 2012 9:43 pm
Posts: 101
I've always found this site very informative. in the past, really not interested in dead cats, just wanted to get an idea of what and where to buy a pump chamber!!


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 10, 2017 12:06 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
hughnique wrote:
I've always found this site very informative. in the past, really not interested in dead cats, just wanted to get an idea of what and where to buy a pump chamber!!


But why do you want a pump ??, most septic tanks and drainage fields work by gravity, also I would be guided by SPANC now, they are the masters of what you can and cannot do, and if what you have done, in their opinion does not conform, out it must come at your cost

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 10, 2017 12:34 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
hughnique wrote:
I've always found this site very informative. in the past, really not interested in dead cats, just wanted to get an idea of what and where to buy a pump chamber!!


My response was to Dave, as said before you don't need a pump.
Except if like a neighbour here your drains are above the foss?

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Tue Jul 11, 2017 7:15 am 
Offline

Joined: Thu Jan 26, 2012 9:43 pm
Posts: 101
It is becoming increasingly popular to see installations with a large mound in the garden, or normally what would have been deemed as gravity systems where the actual filter beds are so far distant from the actual fosse tank that a pump has been installed to facilitate the water delivery to them. Perhaps, in the first instance, it may be a matter of levels or indeed that the surrounding soil does not provide a good enough drainage so the filter bed is raised. As for the involvement of SPANC, I would like to keep their involvement to a minimum, obviously they are there to certificate and inspect the work, but as for giving advice to someone doing it themselves is questionable. I went to a pal's house yesterday who had his work carried out by a recommended contractor last year, the anomalies between his installation and mine are somewhat disturbing. I have two solid effluent pipes from two different buildings and where these two connect to the fosse I have to install a regard. He has the same but that was not imposed on him they just meet up in a tee somewhere under the ground, no rodding access, no audible alarm in the case of pump failure, and he tells me that after the SPANC mans initial visit, at the absolute commencement of the work, where it was obvious he and the contractor were good friends, he never showed up until a month later to inspect and certificate it all. That was when all the soil had been reinstated, so his inspection must have been quite limited, or am I being naïve??


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Tue Jul 11, 2017 12:19 pm 
Offline

Joined: Tue Feb 03, 2009 12:08 pm
Posts: 2067
Location: Zurich/Basel and Suffolk
Fascinating thread - would like to hear Peake's comments on what the new standards entail.

as for the bumps in the garden - aren't those Klargester type mini-sewage plants rather than plain tanks?

J


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Tue Jul 11, 2017 5:16 pm 
Offline

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 9766
Location: Alpes-Maritimes
Just received the official SPANC report for my new fosse, passed with flying colors. I should think so for what it cost. The guy from Suez took about 20 minutes, everything was left uncovered for his visit. It's now all buried again.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Tue Jul 11, 2017 9:32 pm 
Offline
Site Admin
User avatar

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 13943
Location: Was Plouasne 22830, now Ploeuc sur Lie 22150, France
I like the Sotralentz tanks, but (and a big but) I disagree with only one tank with a basket as a filter, there should be two tanks linked together via "dip pipes, so that the pipe discharges the liquid below the floating curd of grease, and not to low as to disturb the solids at the bottom of the tank, the first tank is the anaerobic tank, where the bugs don't need air to breath and digest the crap, the second tank is the aerobic tank, where the bugs need air to breath to help break down what's left of the solid matter, I have seen the outflows of a septic tank have a small catch pit to collect the "humus" or colloidal matter which can block the porous pipes in the drainage field, and I have seen a tipper which slowly fills up with the liquid and when full throws the contents alternatively left and right to pipes leading to the drainage field, so that there is a full discharge of the liquid to flood the pipes in the drainage field, instead of just a dribble of liquid from the tank when an appliance is used
The biggest problem with the basket is that it needs to be pressure washed to clean it, which means a Hazchem type of suit, unless you enjoy being sprayed with high pressure shit

niemeyjt wrote:
Fascinating thread - would like to hear Peake's comments on what the new standards entail.
as for the bumps in the garden - aren't those Klargester type mini-sewage plants rather than plain tanks?
J


The new standards should entail conforming to the law, the first thing is to establish the porosity of the ground and how far below the surface of the ground is the water level, the ground workers will be known to the inspectors after a time, those that need to watched, and those that can be trusted to do a good job
The round top of a Klargester tank more than likely is a cover for a set of fluted turning discs, slowly turning and dipping the discs into the liquid just below the centre line of the discs, the theory is that the discs will over time pick up enough surface film to break down the liquid matter, I love the crappy things, even more than the divel loves holy water, there made with fibreglass, and crack when the f,ing lazy sods of ground workers hold them down with a digger bucket, to stop them floating, instead of filling them with water, when concreting around the tank

A couple of links, http://habitat.sotralentz.com/index.php/en/brochures/films

http://habitat.sotralentz.com/files/ANC/A64-II-08-11.pdf, septic tanks and different types of drainage field

I must admit that I do like these,

_________________
Three meat and one veg

An old wild fowling motto : little powder, plenty lead, kill 'em dead

English born, Living in France, Therefore European

http://www.peakeenergies.fr/

Forum Admin


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Tue Jul 11, 2017 9:49 pm 
Offline

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 9766
Location: Alpes-Maritimes
To get planning permission for my, almost complete, extension and renovation I had to have a geologists report for the fosse and a water retention basin - which was a surprise as I have a valon next to my property - but they are the rules. He measured the soil absorption rate and lots of other amazing stuff and provided plans for the fosse and basin to the mairie.

All conforms, so when I come to sell it all should be OK. I'm lucky in that I have a fantastic builder who knows his stuff.

I admire people who do this on a DIY basis.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 17, 2017 7:13 am 
Offline

Joined: Thu Jan 26, 2012 9:43 pm
Posts: 101
Sotralenz is the fosse I purchased and installed, mainly price driven, as it was initially the cheapest, and therein lies the rub. The two inspection lids are manufactured to be sitting directly on top of the tank housing so in order to get a bit of whatever over the finished project, normally soil, it has to be sunk a couple of feet below finished ground level. Then in order that the inspection lids are above or flush with the ground the use of extension collars or Rehausse, is required, these consist of a bit of circular plastic, like a large ring, which screws on to the inspection hole and then the lid screws on the top of that, thereby extending the level of access to a convenient situation. I say they are made of plastic, but I am wondering if some element of precious metal is involved as we have a 400 mm open ring some 250 mm in height, probably made of recycled lemonade bottles, all for the princely sum of 60€, so 4 on each lid adds a whopping 480€ to the price, absolute daylight robbery.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 17, 2017 8:27 am 
Offline
User avatar

Joined: Thu Feb 05, 2009 1:17 pm
Posts: 883
Location: Minervois Nr Carcassonne 11
We have just had a SPANCing before our house sale. One of our friends, who not only speaks very good French, but is also a consultant for a world wide water purification company and knows his stuff on the things, was present for the inspection. The SPANC bloke was really helpful and gave full explanantions as to what he was doing and why. The result was that our fosee, built in 1982 along with the house, doesn't meet todays standards. We were told that we would have to get a devis for a replacement and that the normal thing would be to pass this over to the buyer who would have a year to do the change. The change is mandatory, but if the new owner didn't want to do it they didn't have to!

Don't ask! I couldn't work it out either? It's mandatory if you want to? This must be France :-? :-?

So we got a fosse installer in for a devis and he told us the same thing. He also said that if the buyer was a forigner they would change it and if they were French they would put the devis in a draw and forget it because nobody would ever be bothered to check it x_x x_x

_________________
John.
Never forget that you are unique, just like everyone else!
My woodturing
http://johnamandiers.wix.com/johns-w-o-w-1


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 17, 2017 2:29 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
Yes true this is France, twice here over the years i have been told that the Fosse doesn't conform but have ignored it as I well know that it works well. The last was six years ago on the purchase of this house here.One day when funds are available I'll get a new one installed with a coconut fibre filter, which a French builder friend thoroughly recommends.

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 17, 2017 4:35 pm 
Offline

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 9766
Location: Alpes-Maritimes
The bit that amused me was the need for ventilation higher that the house. The builder put it up a tree, the inspector noted it and then when he had given his blessing and gone, we took it down again and reduced it to a couple of meters on the understanding that if needed it could be changed. Seems it never gets checked again and if so, who cares. It will be interesting to see who checks that the water retention basin conforms to plan.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 17, 2017 7:08 pm 
Offline
User avatar

Joined: Sun Feb 01, 2009 6:50 pm
Posts: 4798
Location: somewhere in the "pays de dropt"
DaveW wrote:
The bit that amused me was the need for ventilation higher that the house. The builder put it up a tree, the inspector noted it and then when he had given his blessing and gone, we took it down again and reduced it to a couple of meters on the understanding that if needed it could be changed. Seems it never gets checked again and if so, who cares. It will be interesting to see who checks that the water retention basin conforms to plan.



??? Normally it's just higher than the nearest window.

_________________
Ex nihilo nihil fit.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Mon Jul 17, 2017 7:48 pm 
Offline

Joined: Sat Jan 31, 2009 2:29 pm
Posts: 9766
Location: Alpes-Maritimes
Papibryn wrote:
DaveW wrote:
The bit that amused me was the need for ventilation higher that the house. The builder put it up a tree, the inspector noted it and then when he had given his blessing and gone, we took it down again and reduced it to a couple of meters on the understanding that if needed it could be changed. Seems it never gets checked again and if so, who cares. It will be interesting to see who checks that the water retention basin conforms to plan.



??? Normally it's just higher than the nearest window.



Not here.


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Tue Jul 18, 2017 9:33 pm 
Offline

Joined: Sat Jan 31, 2009 11:04 pm
Posts: 912
Location: 46
We are on the market, got Aquaeso in (used to be SPANC but all regionalised now and not a question of choice) who were here for all of 5 minutes and a month later I'm still waiting for a report and what's required to bring our 70's FS up to scratch.

Nowt wrong with it though IMO, the ground here is that porous that the 1.5" outlet from the pool backwash is gone within half a meter and being on on a hillside we are probably several 10's of meters above any underground water resources.

Had it emptied for the 2nd time in 10 years a few weeks back, first time was just after we'd bought and only because I wanted to check it out and repair some damage to the pipework where it entered it at the side and start with a clean slate so to speak.

Firmly convinced that replacing is more a job creation/money making exercise than anything to do with the environment.

_________________
Anything found here will have been inserted by the site NOT me !


Top
 Profile  
 
 Post subject: Re: House drainage, Fosse septiques and mains drainage
PostPosted: Wed Jul 19, 2017 6:50 am 
Offline
User avatar

Joined: Thu Feb 05, 2009 1:17 pm
Posts: 883
Location: Minervois Nr Carcassonne 11
It would need to be a VERY low window here to conform :shock: Our vet pipe sticks all of about 18" out of the ground and it's a nice asbestos jobbie too !!

Still OK though until it's moved and the fosse changde. I put a carbon filter on it and the SPANC bloke said 'pas de problem'. It doesn't smell but if it did I'm not too worried because the prevailing wind is the Tramontain, NW, and it just blows straight towards the neighbour from hell next door :-bd :-bd :))

_________________
John.
Never forget that you are unique, just like everyone else!
My woodturing
http://johnamandiers.wix.com/johns-w-o-w-1


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 34 posts ] 

All times are UTC + 1 hour


Who is online

Users browsing this forum: Bing [Bot] and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  



Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
greenmiles v1.1 designed by CodeMiles Team -TemplatesDragon-.