Episode 24 – Part 1 – An Overview of Off-Mains Drainage in the UK with James Warren, UKDP

In this week’s episode, we are speaking with James Warren from UK Drainage Professionals!
 
Across the three parts of this episode, we are discussing everything off-mains drainage, the basics, the legislation, and the key things to look out for. 
 
James is incredibly passionate about off-mains drainage, its impact on the environment, and helping people to really understand a quite complicated and less common topic. James has an enthusiasm that you can’t help get energised by. 
 
James’s experience has been gained in both the insurance and drainage industries. He started his career working in claims management for the UK’s largest insurer, before moving into the drainage industry in which he had the opportunity to combine both skills. James is our expert on anything from repair scopes to assessing insurance cover. 
 

In Part 1 of this episode, we start with an overview of off-mains drainage: 

🏘️ How many properties are off-mains drainage in the UK

🪣 The differences and costs of septic tanks and sewerage treatment

⚖️ Who is responsible for reporting on drainage in a property sale

💦 Complexities of maintenance with shared off-mains drainage or drainage located on third party land

🌍 The potential environmental impacts of off-mains drainage

Transcript

The following transcript is autogenerated so may contain errors.

 

Matt Nally  

On this week’s episode, we have James who is the Technical Director of UK Drainage Professionals. So thank you for coming on. Absolute pleasure. Thank you for having me. For anyone that doesn’t know you joining give us a background of to sort of who you are, what you do, and then we can go from there.


James Warren  

Yeah, of course. I make this as short and sweet as possible. It’s not much of an illustrious career, but it’s a quirky one. So yes, I’m a director of UK DP UK drainage professionals. We are a specialist off mains drainage company. So we focus predominantly on drainage systems that are not connected to the main sewerage systems. We work nationally have lots of engineers and repair crews. And we just try and make sure that the environment has been protected by making sure the correct product is inserted in the ground. And following all the correct regulations. It almost sounds if that’s scripted, but it’s not.


Matt Nally 

Good elevator pitch. I like it. Thank you. I suppose there’s a few topics we want to cover today. First one, I suppose would make sense to cover, I suppose an overview of off mains drainage. So just start with what it is how many properties are affected or that type of stuff?


James Warren  

Absolutely. So in a weird way, because it’s given so little focus, we have to work in reverse. So when we look at the potential numbers that are off mains or off grid, as it’s sometimes referred, we have to look at the only resource which is the ONS about 96%, they state of property stock housing stock is connected to the main sewer system. So in default, about 4% isn’t, so that roughly translates to a million properties in the UK that have their own off managed drainage system, their own private drainage system. And at the moment, those options are either a septic tank, a sewage treatment plant or a cesspit. So, or normally contained within the property boundary, sometimes not. But we can go into that. But effectively, yes, the customer will not be paying sewerage rates, but they will be paying for the maintenance and upkeep of their own private drainage system.


Matt Nally 

Interesting. Okay. And is it is it does it affect both residential and commercial properties or predominantly residential issue?


James Warren 

It is predominantly residential? Yes, you can get you know, we were talking about off mains, it is predominantly rural and semi rural setting. So yes, you can have commercial properties on off many streaming systems. But the absolute vast majority of what we do is residential, whether that’s individual dwellings, or which is quite a common affair, a group of properties on a shared system, I think the most we’ve ever had is about 20 ish properties, sharing a system like this, although we’re working in one at the moment, which is a complete estate in Peterborough, which has about 55 properties until a huge treatment works. But typically we’re talking small residential domestic, one, two or three properties that that’s kind of the norm, the smaller scale of things, the bread and butter. Definitely mentioned


Matt Nally  

there were a few different types of offerings drainage. So why might want to use over another? Is it down to sort of locations it down to the volume of


James Warren 

it? That is a brilliant question. And I knew you’d have brilliant questions. And it’s really down to whether the ground is suitable to have a soaker installed. So whether the ground is permeable, and whether it’s able to dissipate the water that might be leaving the back end of a septic tank. It might be that there’s not enough room to put in a certain system. It may be that the ground is really bad. There’s lots of parameters and characteristics that have to be sort of thrown in the mix as early as possible. If you’re looking at a new build, there needs to be a lot of due diligence. Where’s the nearest main sewer? Are there any water courses? But if we’re replacing an old system with a modern day system, it’s really a case of where is this system going to discharge Oh, or can it discharge anywhere? If the ground is awful if it’s clay and it’s not going to dissipate any water? If there’s no water causes anywhere, if there’s no main sewer anywhere, it may be that your only option is to instal a cess pit, which is effectively just a bloody great holding tank that has no exit, there’s no outlet to it. It just takes the wastewater from the property fills up, it needs to empty it with a vacuum tankers suck it all out. And that process repeats, it needs to enter that eight times ish a year, it gets mega expensive. It’s a perfectly legal provision of drainage, but it really is a last resort. So it’s all about looking at the immediate surrounding area, checking the ground conditions and then tracking back to see which system will suit that site.


Matt Nally 

That’s a good point. So what are the typical costs then with off my agenda? I know it’s gonna vary massively depending on the type of thing you instal. But in terms of like, having the clearances if you have a cesspit, or even over instal intimate things, what are the How long will they last as well?


James Warren  

Yeah, yeah, brilliant question. Again, I mean, if we’re looking, let’s say typical three or four bed property, if we’re not having to dig because the depth of the installation is governed by the depth of the pipe work that’s already at the property. So effectively, if we’re looking at an average installation with a pipe works at, say, half a metre deep, you can put a septic tank in a drainage field, which is a modern day soak where you can get that in the ground, that easily 10,000 pounds. If you want to upgrade that to a sewage treatment plant, where it’s going to cost you more to buy the product. It’s going to have electricians cost on top of that, the drainage field can be smaller, it’s a bit boring, but I can explain why later, you’re probably looking at 1213 14,000 pounds for the sewage treatment plant and the drainage field. But if you’ve got to go for assessment, even though it’s the most rudimentary product, because it’s just a big tank, they’re huge. They’re absolutely huge. So you’re probably looking at at least 15 to 20,000 pounds to get that in the ground. But that gives you no treatment, there’s no software on the back end. And it’s the worst option for the environment. Because if ever there’s a structural breach on that cesspit, you’ve got that waste going straight to ground, it’s going to hit an aquifer find surface water, and it’s a quick way to pollute. But um, yeah, all three options are legal, most expensive is the worst option, which is the testbed. But then if you if you’ve got no option, and you have to have some legal provision of drainage, you have to have that septic tank is great, because there’s no electricity charge. And the sewage treatment plant gives you the best treated effluent is better for the environment. But you’re looking at a few 1000 pounds more than going for a septic tank. Most of the manufacturers give anything from a 12 month to a 25 year life warranty on the asset itself on the shell. And they normally give two to three years if there’s any inner workings, any moving parts, compressors, stuff like that. But you’d be disappointed if they didn’t last 3040 years. Because they’re glass reinforced plastic, they’re normally eight mil thick. They’re built to last. And if they’re installed correctly, they shouldn’t move when they’re installed. So that yeah, they should be good for decades. Awesome.


Matt Nally  

Okay. So then one thing you touched on a moment ago was the issue of location. So sometimes, obviously, these are quite big. So what causes it to sometimes not be within the boundary of a property? Is it that historical changes and boundary or is it just as is


James Warren  

the most common one we see is perhaps a septic tank is just inside the customer’s boundary line. But because the the original land was so farmland, and they’ve just sold off segments over the years, exactly that there’s boundary changes, so the soakaway might be on third party land, and the septic tank is on private land. But it all it all used to be one piece of land, so it didn’t matter. But as you say, as boundaries change, historically, that can change. Sometimes if you have a shared system, you might have three properties in a row, and the septic tank has to be on one of those three, it can’t, it can’t stagger all three properties. So you will have one poor property that has this septic tank in their back garden, for example. And the other two, they will just have manholes and pipe work under their property, they won’t have any physical assets inside the curtilage of theirs. So it all depends on the dynamic as you say that the history of the boundary is changing. But it is sometimes can get really tricky. And I could bore you to tears with this, the amount of times we get involved where there’s an easement for perhaps a soakaway that’s on third party land, the soakaway fails for whatever reason, it’s coming to the end of its life tracks has gone over the pipe, whatever it might be, but the easement will always have a specific physical footprint. So an also quite might be a rubble pit, just backfield with brick work and stones and what have you. We’re a modern say clay has to be perforated pipe and a series of pipe work which will absolutely be bigger than the soakaway footprint. So that easement has to change and there’s no requirement from the third party In order to agree to the easement being changed to accommodate the larger drainage field, then you’ve got to look at an in boundary solution. And that means it might have to be bespoke, because typically that you haven’t got much room to play with. So that can cause a hell of an issue. Because if you go bespoke, it normally means you’re going expensive. So just because you think I could just throw a brand new soakaway in, it’s not that straightforward. But these are, these are the complexities that no one knows about. Very few people care about, unless you are directly involved, and then you have to care.


Matt Nally  

We’ll come on to the why is it not? Well, in a minute, but my only other question on that then is, I suppose if it’s, if it’s just a single property running off that off Main drainage is slightly simpler, even if you’ve got the boundary issue, you can still deal with it yourself. If it’s a shared one, how does that typically get managed between different parties do they tend to have some sort of sort of leasehold effectively our sink fund or something that they pay into to help maintain that, or it can get complicated,


James Warren  

it can get very complicated because it’s very rare that there’s a written agreement between the shared parties, what typically happens is that the property owners have been there for many years, they’ve always agreed to just pay a third of the emptying, you know, typically, you’re only looking at, say 150 to 200 pounds a year for one septic tank empty, even if it’s a big shared system. So if you split that three or four ways, or equally depends on how many share parties you have, it’s not a great deal of cost. The only issue comes into play, if if a property is sold, someone doesn’t have the tank on their land. They say, Well, it’s a verbal agreement, I’m not happy with that. I’m a single person using this system, you’re all families, I want to pay less, even though that’s not how it works. People, they like to introduce their own logic on these things. And that can cause a real issue. So you’re absolutely right, any shared scenario should have it formally written. In my opinion, it works beautifully when there’s a residence Association. And this just forms part of that agreement under the heading of that association. But that is so rare in the last, in the last few years, I can remember literally one or two that have had formal agreements set up, where it’s set up. It’s beautiful. It’s so easy, you refer back to a certain paragraph, and everyone has to agree, where there’s where it’s just a verbal historic agreement, it can get super messy, so you just have to try and play. Sometimes we feel like peacemakers or or some sort of dispute resolution on but but that’s what you need it even though it’s just drainage, it can cause like crazy emotions between neighbours. But yes, if, if I had my if I had my wish, written formal agreements between all shared systems. Absolutely.


Matt Nally 

I suppose in terms of the, we’ll come on to why is it not well known? But who’s responsible then in the home buying process? For example, for flagging this up? Is it the surveyor to pick it up on a survey or considering not maybe every property gets a survey? Is it up for the conveyancer to pick up on or is it a mix?


James Warren 

It’s a great question. Again, it’s a great question. If you go to I never going to touch on on the governance and the general binding rules. It does actually slipper it stipulate that the operator, which is I, the asset owner, the property owner, should make the purchaser aware of what the system is, how it’s maintained, and who maintains it. That’s actually part of the regulatory reform. So it should start with the vendor. But of course, the surveyor has to grade the drainage system, they have to identify it. So you could say it’s on them as well. So as the ultimate, the ultimate stopper is the conveyancer. But when and also is the estate agent part of that process as well. You know, there’s in a seller’s packet in the questionnaire, all of these things should be flagged up. You know, who has ultimate responsibility? It’s a brilliant question. Speaking to conveyancing, they will probably say themselves, but from my personal experience of being directly and indirectly involved in PEI claims, it seemed the buck seems to stop with the surveyor if they haven’t picked up on it. So I don’t know the actual answer to that I can only speak from firsthand experience where conveyances are typically saying they’re the final safety net, but only see any any comeback any negativity towards the building surveyor. So yeah, it’s a bit of a quirky one.


Matt Nally 

But we’ll come on to a bit more of that in a moment I suppose. My final question around this asset side of things is Why is often mains drainage not known that well, is it purely because it’s such a, I say it’s a small percentage of properties? It’s a large number in real terms that that are affected. So why is it not that well known? Yeah.


James Warren 

I wish I knew I wish I knew I suppose. Yeah, well, so is roughly one in 20 properties are off Main. So yes, not huge, but when you when you You like it is a million properties give or take and might be fractionally more now, I don’t really know in in England, where there’s a largest percentage of these, there is no database for them. So, in default, there is no ability for communication from Defra, the Environment Agency, any other governing body who may have some impact in your any stakeholder has impact on these systems. The the only asset owners that are on the radar, the Environmental Agency, or the property owners that need to have permission for a discharge or consent to discharge. So a tiny proportion of those in England will be on the radar. But yeah, I don’t know, I think sometimes we have drainage, I’ve been told this for my whole 25 years in the drainage industry. Unfortunately, that out of sight out of my mentality is so true. And we’ve automated drainage systems, you might enjoy three or four decades trouble free. So you’re only it’s only going to become a problem. When you have an issue when you can’t flush the loo if there’s some nasty odours, you know, something as fundamentally rudimental as that. But yeah, because it is such a tiny proportion of the overall housing stock is st doesn’t seem to get any press, which I find ridiculous because it from an insurance perspective, we’re involved in insurance claims with these things, you might look at an average claim value for say 800 pounds for a drainage system on an on main system is connected to the sewerage system. But the average price is 13 to 15,000. For an off mainstream system. So yes, there are a tiny proportion. But it’s a flipside on the ratio when it comes to the cost of putting the right. So you would you would have assumed that they should get more press because they’re more damaging to the environment when they go wrong. There are a lot more expensive than normal drainage systems when they go wrong. And there’s a lot of specific governance over it. But still, excuse me, it’s still there. I don’t know. There’s just, it’s just not sexy. It’s not glamorous. And I don’t know, I don’t know how to gorgeous chaps like ourselves. If we can’t make it more publicly aware, then I don’t know who will!


Matt Nally 

Awesome. Well, I think tune in for part two, and we’ll look at compliance and governance. 


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