Septic Tank Soakaway

purple_reign

We're purchasing a house that has a septic tank. We've had a septic survey conducted which has found that it needs a new drainfield/soakaway. We've never owned a property with a septic tank and I'm quite concerned about this. I imagine a new soakaway is quite invasive and will completely ruin the garden as it is. The house isn't on a big plot and is relatively close to a main road surrounded by other houses, so I'm surprised it's not connected to a main sewer like others. The septic tank is apparently ok but the soakaway isn't draining properly. I suppose my question is, is this something that we should negotiate price over? Is it big work?  Is there anything I should consider being the purchaser? The current vendor has advised the estate agent that the drainage company told him that all was well and that it was just draining a little slower than usual, but that's not what they relayed to me. I'm awaiting the actual hard copy of the report but I don't know who to trust in situations like this. Any advice from personal experience would be highly appreciated. I will also attempt to get some quotes for the work when I have the actual report.
Thanks in advance!

foxy-stoat

Septic tank required emptying, treatment plant requires a soakaway and maintenance, which is it, dont rely on the estate agent telling you any information.

See what the report says first.

The price your paying was probably based on a functioning septic tank so you should adjust your offer to cover any works required to get it functioning.

AdrianC

Let me guess - this "septic survey" was done by a company who, among other services, install tanks and soakaways?

Did they give any more detail?

Yes, soakaways can collapse, which will require redigging.

They can also get blocked - especially when people get competitive over long they can leave a tank unemptied... But, much of the time, they can then be jetwashed out - a relatively simple process.

If you are near to a mains sewer, then the simplest solution will be to get the house connected to that.

If not, you may find that the cost difference between upgrading to a treatment plant and reinstating the soakaway is relatively small - the extra cost of the plant itself will be offset by less invasive groundwork, together with better compliance with environmental legislation and simply nicer output...

purple_reign

foxy-stoat said:

Septic tank required emptying, treatment plant requires a soakaway and maintenance, which is it, dont rely on the estate agent telling you any information.

It was the company that conducted the survey that relayed this info over the phone...but I haven't seen the actual report yet. This will hopefully be sent over later today. It was the vendor that advised the estate agent that nothing was wrong with it. I will obviously go with what the report says when I get it.

AdrianC said:

Let me guess - this "septic survey" was done by a company who, among other services, install tanks and soakaways?

Did they give any more detail?

I'll look into this...they could well offer other services that benefit them to advise of expensive repairs, but I've paid for an impartial survey so I would sincerely hope not.
I only spoke to them on the phone but they said the following:
Soakaway wasn't doing it's job properly
Man hole was blocked and full on arrival and discharge pipe sat full throughout the survey
There was foul water going into a rainwater pipe...connected up wrongly but can be easily fixed apparently
Everything he said kind of goes straight over my head, I wish I understood better about these things.
Connecting to mains drain would take the hassle away for us but we have no idea how much this costs and if it's even possible.
More research on our part is needed I think.
Thanks for the replies.

AdrianC

purple_reign said:
It was the vendor that advised the estate agent that nothing was wrong with it.

Uh-huh. And lemme guess, he's not had to call anybody out to it for years and years...? (including emptying)

AdrianC said:

Let me guess - this "septic survey" was done by a company who, among other services, install tanks and soakaways?

Did they give any more detail?

I'll look into this...they could well offer other services that benefit them to advise of expensive repairs, but I've paid for an impartial survey so I would sincerely hope not.

See also: Damp surveyors...

I only spoke to them on the phone but they said the following:
Soakaway wasn't doing it's job properly
Man hole was blocked and full on arrival and discharge pipe sat full throughout the survey

I was right... Not emptied for years.

Everything he said kind of goes straight over my head, I wish I understood better about these things.

Septic tanks are very simple things really.

Everything that goes down the bog goes into the tank.
Poo-munching bugs then do their thing on it, while it all settles and naturally separates.
The cleanish water in the middle then gets filtered out to the ground via the soakaway.
(Cesspits are different - everything, including all liquids, simply stays there waiting to be emptied every few months)

What the bugs don't eat needs emptying periodically... And that's the bit people like to forget - because all they see is an expensive man with a truck come and hoover it out.
If the hoovering doesn't happen, the level of the "sludge" will rise and go out of the outflow into the soakaway.

Septic tanks work best when ONLY human waste and looroll go into them.
If you flush things down that the munchies don't like, the hoovering will need to be done more often.
If you flush things down that the munchies REALLY don't like, they'll die and the outflow won't be cleaned. Bleach is one of the worst things - eco bogcleaner is fine.

Treatment plants simply do a better job, and the liquid that flows out doesn't need to be filtered through the soil - it can run straight into a waterway, even. The manufacturers allege the outflow is drinkable...

Connecting to mains drain would take the hassle away for us but we have no idea how much this costs and if it's even possible.

Talk to the neighbours. If they're on mains, it'll be doable. It might not be cheap, and there is an ongoing cost on your water bill, of course, but...

purple_reign

Cheers AdrianC...appreciate your time!
I did laugh out loud at your response regards it not being emptied...the vendor categorically stated that he has it emptied yearly, but he also said he wasn't in a chain...and guess what, he is. 
Can't trust folk when it comes to selling their home. Have to do your own due diligence and make informed decisions it seems.

greatcrested

Septic tanks need emptying every year or 3 depending on size of tank and size of population. If not emptied, the 'solids' will gradually build up so that instead of just liquids running out to the soak away, solids also run out, blocking the soak away.

Soakaways can also fail over time for other reasons.

And nowadays the requirements for soakaways are more stringent than, say 10 or 30 years ago. The liquids must dissipate into the soil at the correct speed. A percolation test will check that.

The new 2020 rules mean that on sale, a sewage system must comply with the new rules (though until a sale, a system that was compliant when installed eg 30 years ago, is acceptable).

Your options are

* test the soakaway and clean/flush/repair it so itworks properly

* dig a new soakaway - yes, very disruptive if you have a 'nice' garden, though a decent contractor will do his best to protect and make good eg covering land where a digger is used, replacing turf on a lawn, etc

* connect tomains sewer if not too far. Contact the water company for feasibility/cost. If the distance is oo far, and there are two+ properties (neighbour?) needing a new mains sewer, the water company must supply this under S98 of the Watr Industry Act 1991

* install a Small Sewage Treatment Plant. These cost around £2-3K plus installation, and the outflow is (near) drinking water quality, so can be released into a watercourse, road drain etc, doing away with the need for a potentially expensive new soakaway.

AdrianC

purple_reign said:

I did laugh out loud at your response regards it not being emptied...the vendor categorically stated that he has it emptied yearly, but he also said he wasn't in a chain...and guess what, he is. 
Can't trust folk when it comes to selling their home. Have to do your own due diligence and make informed decisions it seems.

A cynic might think the tank was not alone in being full of...

purple_reign

Thanks greatcrested for all the info! I'll look into the options suggested 

purple_reign

AdrianC said:

A cynic might think the tank was not alone in being full of...

Haha spot on!

greatcrested

purple_reign said:

Cheers AdrianC...appreciate your time!
I did laugh out loud at your response regards it not being emptied...the vendor categorically stated that he has it emptied yearly, but he also said he wasn't in a chain...and guess what, he is. 
Can't trust folk when it comes to selling their home. Have to do your own due diligence and make informed decisions it seems.

Easy. You ask to see a copy of the contractor's invoice for emptying. If he's lost it' you ask for name of the contractor.