Septic Tank Infiltration / Soakaway Field

[Ukjay]

Hi,

We have recently looked at a house which has the obligatory Septic Tank and Infiltration Field system, whereby as I was looking around it - I noticed it has got recent evidence that it overflows onto the ground, so I suspect the infiltration system / soakaway system is either backed up - or not effective enough due to the amount of rain and the type of soil (reddish clay / claggy surface).
We have advised the owner that this will be checked and there may be a cost he will incur to cover the remedial works for this system replacement to either come off the selling price or hi carries out the work prior to exchange of contracts.

Now, there is a dry ditch litterally 3 mtr from the septic tank location which cannot be used if the system is ripped out and a waste treatment plant installed, and the next ditch with running water is around 120 meters away, which would need the pipework to go around a barn and stables and across a small area of paddock, so what would you feel is a likely cost to get someone in to do the works (we would arrange to get the treatment system on site etc), so that I have a good estimate on costs likely to be incured from people who have had to get this done?

 

[milkloss]

Are you allowed to reinstall an new soakaway system or does it have to comply with the latest regs? I'm not sure these new things are that great compared to a proper brick built tank and decent infiltration.

 

[br jones]

If you have the ground put a new bigger soakaway,far better than a treatment plant ,far cheaper ,soakaways last around 25 to 30 years ,then block up with fats etc ,just a new one ,30 to 40 metres in length,16 ton of 40 mm clean stone ,500 in materials, 2 days digger ,job done

 

[rob1]

Hi,

We have recently looked at a house which has the obligatory Septic Tank and Infiltration Field system, whereby as I was looking around it - I noticed it has got recent evidence that it overflows onto the ground, so I suspect the infiltration system / soakaway system is either backed up - or not effective enough due to the amount of rain and the type of soil (reddish clay / claggy surface).
We have advised the owner that this will be checked and there may be a cost he will incur to cover the remedial works for this system replacement to either come off the selling price or hi carries out the work prior to exchange of contracts.

Now, there is a dry ditch litterally 3 mtr from the septic tank location which cannot be used if the system is ripped out and a waste treatment plant installed, and the next ditch with running water is around 120 meters away, which would need the pipework to go around a barn and stables and across a small area of paddock, so what would you feel is a likely cost to get someone in to do the works (we would arrange to get the treatment system on site etc), so that I have a good estimate on costs likely to be incured from people who have had to get this done?

Why cant the dry ditch be used ? I thought that was the whole point of treatment plants

 

[Bbritton]

br Jones is right. We would cost replacing or enlarging a soak away much cheaper than installing a new system.

You would be looking at the cost of installing a new treatment plant and running that length of pipe to be around 50% more expensive than enlarging or renewing the current soak away

 

[Sharpy]

Hi,

We have recently looked at a house which has the obligatory Septic Tank and Infiltration Field system, whereby as I was looking around it - I noticed it has got recent evidence that it overflows onto the ground, so I suspect the infiltration system / soakaway system is either backed up - or not effective enough due to the amount of rain and the type of soil (reddish clay / claggy surface).
We have advised the owner that this will be checked and there may be a cost he will incur to cover the remedial works for this system replacement to either come off the selling price or hi carries out the work prior to exchange of contracts.

Now, there is a dry ditch litterally 3 mtr from the septic tank location which cannot be used if the system is ripped out and a waste treatment plant installed, and the next ditch with running water is around 120 meters away, which would need the pipework to go around a barn and stables and across a small area of paddock, so what would you feel is a likely cost to get someone in to do the works (we would arrange to get the treatment system on site etc), so that I have a good estimate on costs likely to be incured from people who have had to get this done?

@Nick. Would be the man.

 

[Pond digger]

Why cant the dry ditch be used ? I thought that was the whole point of treatment plants

Just not allowed I believe. I suppose what comes out of the treatment plant needs diluting.

 

[Ukjay]

Are you allowed to reinstall an new soakaway system or does it have to comply with the latest regs? I'm not sure these new things are that great compared to a proper brick built tank and decent infiltration.

Im not sure to be honest as it is the predominantly clay soil, and not sure what the EA would think to that. I will have to at some point have to raise this with them I think, which will probably invoke a site visit.

 

[Ukjay]

If you have the ground put a new bigger soakaway,far better than a treatment plant ,far cheaper ,soakaways last around 25 to 30 years ,then block up with fats etc ,just a new one ,30 to 40 metres in length,16 ton of 40 mm clean stone ,500 in materials, 2 days digger ,job done

As above - will have to check this out as I am not fully up to speed with the current requirements for septic tanks.

 

[suffolksmallholder]

Last one I had done on contract was £8k. Note this was twelve years ago. We went down using a Dando rig. Klargester air bubble system. Hope this helps with a very rough guide. 5 ton machine minimum required on site.
This unit or its earlier incarnation;https://www.kingspan.com/gb/en-gb/p...gester-biotec-domestic-sewage-treatment-plant
SS

 

[Ukjay]

Why cant the dry ditch be used ? I thought that was the whole point of treatment plants

I was led to believe it had to have flowing water in the ditch, but will investigate further, but to be honest - I would rather it not go into the dry ditch, as it has no water whatsoever.

 

[Ukjay]

br Jones is right. We would cost replacing or enlarging a soak away much cheaper than installing a new system.

You would be looking at the cost of installing a new treatment plant and running that length of pipe to be around 50% more expensive than enlarging or renewing the current soak away

I understand the treatment plant costs, that is not where I am keen to understand the costs - it is more the groundworks, stone, pipework etc to get a rough idea.

 

[Ukjay]

Last one I had done on contract was £8k. Note this was twelve years ago. We went down using a Dando rig. Klargester air bubble system. Hope this helps with a very rough guide. 5 ton machine minimum required on site.
SS

Thanks SS,

By Dando rig, are you referring to a drilling line?

 

[suffolksmallholder]

This;

Makes a hole and in my case down as far as and into bed chalk then the water can soak away nicely.
SS

 

[Ukjay]

This;

Makes a hole and in my case down as far as and into bed chalk then the water can soak away nicely.
SS

Interesting - wasn't aware you could do that with a treatment system. Food for thought as they say

 

[Sharpy]

This;

Makes a hole and in my case down as far as and into bed chalk then the water can soak away nicely.
SS

So are you basically discharging waste water into an aquifer?

 

[milkloss]

So are you basically discharging waste water into an aquifer?

I did wonder that myself. Wouldn't want a borehole too nearby!

 

[suffolksmallholder]

Interesting - wasn't aware you could do that with a treatment system. Food for thought as they say

It all depends on the ability of the stratums ability to soak up the water. This was local authority approved in dwelllings unable to connect to a mains sewage system or with gardens too small or too hilly to make good soak-away systems.
SS

 

[suffolksmallholder]

I did wonder that myself. Wouldn't want a borehole too nearby!

In the case where this was, the aquifer was considerably deeper and much further away, but absolutely you do not want a bore-hole in the next door paddock!
SS

 

[Sharpy]

In the case where this was, the aquifer was considerably deeper and much further away, but absolutely you do not want a bore-hole in the next door paddock!
SS

No saying you did anything wrong, but I would say your local authority is very short sighted.