We'd like to remind Forumites to please avoid political debate on the Forum... Read More »
Did I purchase a house with an illegal septic tank?


Hello,
I wonder if anyone can share some advice or shed some light on the next steps I need to take. Apologies for the lengthy backstory.
We completed on our house purchase this January on a 30yr old property with no issues flagged on the level 2 survey or searches by solicitor.
Previous owners installed a new septic tank in December 2020, the “floor plans” provided to the solicitor were what previous owners of the home submitted when they built the property 30 years ago, depicting the tank to be behind the house, and the soakaway to be located across the unadopted road leading to us and a few other properties.
Our sellers have moved the tank to the front of the property and we can see marks in the road that don’t match to where the pipes should have been laid to where the original soakaway was, these new marks look like they go direct to the edge of our boundary which leads to a field with a ditch, and I can see a drainpipe coming out from our land to this ditch. From what I can see on Natural Resource Wales website, there is a water course marked at the bottom of this field but not marked at the top where this pipe comes out to, just the ditch.
There is only two of us living at the property and just two months in we began to notice a smell and wet patch in the corner of the garden. At first we thought it was just winter weather and poorly draining clay soil, then we thought next door’s tank could be leaking into our garden as their plot is slightly higher than ours, so we got a drainage expert out to check it definitely wasn’t us before we spoke to them.
He could only insert the camera halfway as the tank was already full (tank was emptied the day prior to completion mid January) and due to the clay soil the tank has turned out to be the wrong type/system as the liquids cannot drain effectively and are backing up to the house.
We got the tank emptied the same day and reinserted the camera and the pipework in our garden isn’t broken etc, it’s just the system that is not working properly.
During this time our neighbours popped round and we explained the situation. They said they queried when last owner was installing the system as they didn’t believe it to be legitimate/correct to have the pipe opening onto the fields instead of underground, to which old owners brushed them off. We then got in touch with a local septic tank fitter who informed us they attended the property to instal a new tank, they told them they needed a tank with a treatment plant - I have also read that this is the type of tank required to be upgraded to from January 2020 as part of new legislation.
I have contacted Natural Resources Wales as we have a Water Drainage Exemption Certificate, to ask if this set up is legitimate and whether anyone attended the property to inspect and sign off on this certificate with this tank system.
I have also contacted our conveyancing solicitor to request a copy of the septic tank guarantee from previous owners. The question form regarding drainage was answered straightforwardly with yes/no answers and no known issues stated. When asked “Does the water from the tank flow into a watercourse or into land”, they answered “into land (soakaway)”, but in my mind it is above ground and to this ditch so it’s ONto land instead of INto - have I missread or misunderstood this?
I’d like to know does this sound like a legitimate mistake of wrong system put in without knowing any better (despite going against expert advice), or has this been installed against new legislation and the subsequent sales questions answered knowingly incorrectly with a recourse for myself to get this rectified?
Comments
-
What did your survey say about it?1
-
“This type of system relies on adequate drainage into adjoining land but will also require emptying form time to time (emptied the day before we moved in in mid Jan and now again this week - 2 occupants) . Not possible to make specific comments as to it’s overall capacity and efficiency, enquiries should be made to ensure it’s of sufficient size.
Ask legal advisor if registered with Natural Resources Wales (it is).Arrangements for surface water drainage appear satisfactory but have not been tested and the existence of adequate underground drainage cannot be confirmed”0 -
How horrible for you, I am sorry to read this. I shared a septic tank with my neighbours and we started to empty annually when the new guidelines came in, but it was never full.£216 saved 24 October 20141
-
I assume from what you've written that you chose not to have the tank and drainage surveyed by professionals before buying eg(not a recommendation- others are available).Now might be a good time to do so!But from what you describe, yes the septic tank is probably illegally polluting a watercourse.If the seller's answered "into land (soakaway)” and your survey proves this to be inacurate, you might have a claim against them. But enforcing that claim could be slow, require cost, and with no cast-iron guaranteeof success.I would certainly advise, subject to getting a survey done to verify the current set-up, you install a small sewage treatment plant in place of the septic tank, and then continue, legally, to use the watercourse forthe outflow.Get at least 3 quotes, but first research the different manufacturers to identfy the most appropriate for your property.
3 -
canaldumidi said:I assume from what you've written that you chose not to have the tank and drainage surveyed by professionals before buying eg(not a recommendation- others are available).Now might be a good time to do so!But from what you describe, yes the septic tank is probably illegally polluting a watercourse.If the seller's answered "into land (soakaway)” and your survey proves this to be inacurate, you might have a claim against them. But enforcing that claim could be slow, require cost, and with no cast-iron guaranteeof success.I would certainly advise, subject to getting a survey done to verify the current set-up, you install a small sewage treatment plant in place of the septic tank, and then continue, legally, to use the watercourse forthe outflow.Get at least 3 quotes, but first research the different manufacturers to identfy the most appropriate for your property.
I have emailed a couple of companies for quotes, we did have a camera out down from the house to the tank which reported the pipework to be fine, but didn’t go from the tank to the outlet so will get this done ASAP, thank you for your advice.0 -
MoneySavingMiss95 said:canaldumidi said:I assume from what you've written that you chose not to have the tank and drainage surveyed by professionals before buying eg(not a recommendation- others are available).Now might be a good time to do so!But from what you describe, yes the septic tank is probably illegally polluting a watercourse.If the seller's answered "into land (soakaway)” and your survey proves this to be inacurate, you might have a claim against them. But enforcing that claim could be slow, require cost, and with no cast-iron guaranteeof success.I would certainly advise, subject to getting a survey done to verify the current set-up, you install a small sewage treatment plant in place of the septic tank, and then continue, legally, to use the watercourse forthe outflow.Get at least 3 quotes, but first research the different manufacturers to identfy the most appropriate for your property.
I have emailed a couple of companies for quotes, we did have a camera out down from the house to the tank which reported the pipework to be fine, but didn’t go from the tank to the outlet so will get this done ASAP, thank you for your advice.Yes I can understand that.What about the guarantee: * was it transferred into your name? * is the company still in business and if not, is the guarantee insurance backed? * What exactly does it guarantee? Just the tank itself, or the entire system? If the system you may have a claim under guarantee........Solicitor would never visit the property so would have no idea of the outflow whereabouts! Probably assumed same as you: "new system with guarantee".House surveyors don't know about (and generally don't comment on) drainage, other than perhaps to lift a manhole cover and look for blockage Vs flowing water. Certainly not septic tanks, outflows or drainage fields!The new septic tank should have been signed off by Building Control, especially as it was moved. No BC certificate?A quick cheap option would be to pour a (harmless) food dye into the tank near the exit outflow. If it comes out of the drain you spotted that leads to the watercours - there's your answer!
1 -
I understand that solicitor or surveyor wouldn’t have known the specifics but surely if legislation was brought about over 2 years ago now regarding the tanks draining into watercourses surely this sort of question should also be included in their queries.I’ve emailed solicitor for copy of the guarantee so I can find out what it covers. Building Control wasn’t mentioned by them in the conveyancing process; I will ring council to ask, even if they can give me a yes or no answer on whether one was issued for the works would be of help. I will also look into the dye.0
-
I sold my house in March 2020 and my buyer's solicitor sent two full pages of questions about my septic tank .The legislation is here and doesn't seem to have been updated.
Septic tanks and sewage treatment plants: what you need to do: Overview - GOV.UK (www.gov.uk)
Ours was built around 1847, I was always careful and didn't use bleach or biological washing powders. I know our neigbours did!
£216 saved 24 October 20141 -
I may be misunderstanding something, but if the outflow was going direct to a ditch you would see it running pretty much constantly and there would be no impediment to make the system back-up. It seems to me that your system may go to a soakaway in (unsuitable) land as described by the vendor. The pipe outlet you can see may or may not be linked in some way to this conventional, but unsuitable, system.I live in a rural place not unlike Wales and have an indigenous neighbour who won't necessarily follow regulations, so I keep an eye on what he does. About 10 years ago, this chap and his son renewed the drainage field to their septic tank which lies in an adjacent meadow across a small stream. The pipe from the tank crosses one branch of the stream taking the outflow to the meadow, but after the soakaway an underground pipe then goes at right angles and continues to the stream. They've disguised where this pipe ends with a number of large stones. I've kept a close eye on the point where this hidden pipe ends, but I've never seen evidence of anything issuing from it. If I did, I'd be tipping off the Environment Agency PDQ. It seems the drainage field in the meadow is working OK.Could your system be like my neighbour's? It probably doesn't make much difference, as the lack of efficiency in clay soil seems to be your problem, but it might explain the pipe which in the above case seems to be an 'emergency' outflow concocted by slightly twisted and uninformed minds!2
-
Youth_leader ours sent two pages of 14 questions where sellers stated that replaced the tank in December 2020. But not what type of tank etc. Which in hindsight should have been asked.
Woolsery there is a constant trickle from this pipe but not stream-like. The direction that I can see they have been laid by sellers (going off the dug out patches in the road) are either most likely going straight to this pipe or the soak away is under the shed and more farmland directly behind the pipe.0
Confirm your email address to Create Threads and Reply

Categories
- All Categories
- 349.9K Banking & Borrowing
- 252.7K Reduce Debt & Boost Income
- 453K Spending & Discounts
- 242.9K Work, Benefits & Business
- 619.7K Mortgages, Homes & Bills
- 176.4K Life & Family
- 255.8K Travel & Transport
- 1.5M Hobbies & Leisure
- 16.1K Discuss & Feedback
- 15.1K Coronavirus Support Boards