Buying House with Septic Tank Drainage Problems

gail5863

We are buying a house that has a septic tank with private soakaway. The owners told us at the start that they 'rod out' the pipe near the septic tank about once every 3 months, but I phoned the waste company they use (which we have used before too) to check a comment on their invoice that said 'clear roots' and hence became suspicious. Their response was that they have emptied the septic tank at least twice each summer for the past 2-3 years, and have noted 'roots' at the manhole a few feet away from the septic tank, but also upon emptying - roots at the entry point into the septic tank and exit (to soakaway) ends. Have spoken to a drain repair company who said they would not repair due to roots in several places, but replace the tank with package treatment system and new soakaway. The current owners have now admitted the rodding out is much more often - maybe more than once a month. This seems to indicate that the septic tank system (old property maybe more than 50 years old) is failing. We can get a CCTV survey done for a few hundred pounds, but we feel sure the owners know it is a serious problem and yes, the survey will give us the facts, but I feel we already know it needs a new system. Drain guys said budget for about £15-£20K. Whose responsibility is this as it is pre-sale and not declared until after negotiations completed and all well done the line with the solicitors.  Any thoughts or comments on a plan of action?  

propertyrental

The drains and/or tank itself have been broken into by roots that are blocking the system - hence the frequent rodding. Is it the drain leading to the tank, or the outflow leading to the drainage field that needs rodding?

Whichever it is (or maybe both) will need replacing.

That does not explain "they have emptied the septic tank at least twice each summer", Though if the blockage is in the outflow that might explain why as the tank would fill up /overflow. Yuk! Any signs of that?

What condition is the drainage field? Any signs of pooling liquids? Any smell? Or is the drainage field functioning as intended (once the outflow reaches it)?

Are there any watercourses nearby? Stream, pond etc? 

If the drainage field is OK, then option to replace the drains/pipes to or from the tank, and the tank itself.

If the drainage field is passd its best, and you have a nearby watercourse or running rainwater ditch, then option to replace with a small treatment plant (and save money by not replacing/fixing the drainage field).

Whose responsibility is this as it is pre-sale 

Until contracts are exchanged there is...... no contract. It's all down to negotiation. You have discovered an unexpected cost so it's fair enough to reduce your offer, by the amount you estimate it will cost or some intermediate amount.

The seller might or might not agree. If he does not, you can either walk away, increase your (reduced) offer as a compromise and hope the seller then agrees, or swallow your pride, and budget for an extra expense once you've bought your dream house.

gail5863

We are struggling to get ANY info out of the sellers as they are Executors but have been living there for 4 years so they should know! They say the rodding is the pipe between the manhole and the tank, we don't know why the tank has been emptied twice in the summer, the seller just says they don't know, well they obviously do! Probably overflowing - or backing up for some reason -but probably we guess the outflow from the septic tank as that also apparently has roots present. It's all very old (more than 50 years at least). There's no watercourse near enough for this to run into so we believe it runs into a soakaway within the boundary, but no-one can confirm that either! So I think the only solution is new package treatment plant and new soakaway, but who pays for what? We hadn't budgeted for a very large extra expenditure on top of a good price for the property itself (which needs other money spending on it as in tired state). Wondering how to approach this - if it's fair to pay half each or should they be responsible for making sure it is a working system before the sale goes through.

propertyrental

You'd be surprised how many people don't know how their septic tanks work!

" the pipe between the manhole and the tank, " just to be clear as 'the manhole' could be anywhere - is this in the pipe leading from the property to the tank? In which case the pipe would back up (to the house) and /or overflow but the tank would not.

"probably we guess the outflow from the septic tank as that also apparently has roots present. " in which case the tank would overflow.

"the only solution is new package treatment plant and new soakaway, " but you've given no indication that the drainage field is not functioning/needs replacing. All your issues seem to be in the pipework, either from the property to the tank, or the tank to the field.

I suggest a proper survey eg
https://www.ukdpsolutions.co.uk/septic-tanks/surveys
(other companies exist!)

"but who pays for what? "

 It's all down to negotiation. You have discovered an unexpected cost so it's fair enough to reduce your offer, by the amount you estimate it will cost or some intermediate amount.

The seller might or might not agree. If he does not, you can either walk away, increase your (reduced) offer as a compromise and hope the seller then agrees, or swallow your pride, and budget for an extra expense once you've bought your dream house.

ps. For information, a 'soakaway' is used for clean water eg off the house roof. The correct term for your septic tank outflow is a 'drainage field'.

LHW99

If the system is 50 years old, the pipes may well be sectional terracotta. We had some of these on a spring water supply pipe, and its easy for the sections to become displaced and invaded by roots.

If there are larger trees around / ground movement, older drainage pipes can get also broken / blocked / invaded. it means the bad section has to be removed and replaced

The pipes need to be replaced with modern piping and any sharp (eg 90 degree) bends replaced by more gradual ones. The question is what the tank itself is like - have roots invaded it, or is it leaking?

Smells can be a guide, but with people who are not used to septic tanks, it may just need a good bio-treatment to get it going properly. We used to do that once a month (one tablet / cup of enzymes) per month, and no smells.

Drainage fields can also be repaired fairly easily. Find out the company who empty the tank, and talk to them. They may deal with repairs, or suggest someone who does. Unless the tank itself has gone, pipework etc repairs shouldn't be £20k

gail5863

Thank you for help and replies, sorry should have been clearer, the manhole is about 3m from the inlet to the septic tank and they lift the manhole cover and rod towards the septic tank, which apparently clears it. The waste company operator said there are roots on the inlet to the septic tank and also the outlet to the soakaway (which he saw - and pulled some out when emptying). We can't see inside the tank because it's full. We don't know why the tank is being emptied twice (in 3 months) so we can only guess, seller won't enlighten us. Have only visited the property twice and neither time could we smell or see anything horrible in the vincinity of the septic tank. I guess the only way to know for sure is to have the tank emptied and a same day CCTV pipe / tank survey and then try and negotiate from there.

propertyrental

Yes but make sure your survey is by a reputable sewage company as per the link I gave you.

I would not use a bog-standard (pun intended) CCTV drain company unless they also do septic tanks, treatment plants, drainage fields etc.

They may ask you to arrange forthe tank tobe emptied before they survey. Check with them. That would mean seller agreeing and (unless seller agrees) you paying.

youth_leader

We had a horrible situation with our shared septic tank drain,  which involved digging up a lot of watery pooey gravel because it kept backing up.  We thought our neighbour had damaged our soakaway when he had his drive done but he wouldn't admit it, unfortunately we had to go to a solicitor to force him to 'watch' us hand digging it out, and yes, his 'digger' had cracked it.  

I'd pay for a proper septic tank survey, they are disgusting and the further upwind you can be, the better.

gail5863

propertyrental - thank you for your advice, very helpful, will follow the link you sent as I think the only way to know for sure is to have it surveyed and then take it from there.

youth_leader

Good luck gail5863, well worth the money, we had a 'rodding' company in who confirmed our drainage field was knackered - that alone cost £250 about ten years ago.  The vendors are obviously trying not to spend any money and selling with a full tank is repulsive.  I asked my neighbours to agree to have our tank emptied before I went on the market.

propertyrental

youth_leader said:

...... and selling with a full tank is repulsive.  I asked my neighbours to agree to have our tank emptied before I went on the market.

septic tanks are (nearly) always full! They are designed to be full. The solids sink down, the liquids at the top flow out through the outflow.

The only time the tank is not full is immediately after it's been emptied - the purpose of which is not to empty the tank (that would be what happens to a cess pit, not a septic tank) but to remove (most of) the solids at the bottom.

Which should happen rarely, maybe once a year/every two years depending on size of tank and number of people using it. Within a week the tank will be 'full' again, though with less solids.

Completely emptying a tank is never good, as that removes all the good bacteria that are needed to break down the solids.