I have a manhole in my kitchen...what to do?

[MetricMs]

Hi, I really hope someone has some practical advice for me - I have a 1920’s mid terrace house (London) that has a shared pipe running behind a row of 4 houses and then running down to the road and joining up with the main pipes there.

The previous owners built over it and left a manhole for access in the kitchen floor. The floor tiles disguise it well and I didn’t notice it until after the purchase - I was desperate to buy so I probably would have gone ahead with it anyway but I’ve had some panicked moments worried I may come down one morning to find a kitchen full of sewage!

I’m hoping to completely re do the kitchen and I originally thought I should extend the pipes out in to the garden, so if there any blockages they can be dealt with outside my kitchen. The extension was done before the council changed the rules about kitchen manholes and as the council approved the plans the manhole is accepted within building regs.

I have not had any issues with it so far (touchwood) and as our houses were built with the bathroom at the front I’m not even sure if there are sewage pipes at the back - they may be purely for kitchen wastewater?

I’ve recently read that it might actually be smarter to keep the manhole cover, and make sure whichever flooring I use is built to allow access. That if it is done properly there should be a manhole at the pipe (under the floor) and then a cavity and my manhole in the kitchen, so there’s no way a blockage would leak through the first manhole and then up to the kitchen manhole? Apparently the extra bends created by extending pipes out to the garden actually creates more issues with blockages and some councils are now advising to build over the pipes (I’ve emailed my council but haven’t heard back yet).

Does anyone have any experience or advice for me?

Thanks...

@Wingedharpy

That is indeed a beautifully crafted manhole *@beautifullymad*.

@SixQuidGames, Did you mean to be so rude?

[quote ILoveShula]@SixQuidGames, Did you mean to be so rude?[/quote]
Yes.

I used to work for a water company on the waste water network, so I can explain a bit about how waste water networks work.

If the bathrooms are at the front, you could have a sewage system going from the front and the back. It doesn’t happen often but it can. It doesn’t matter too much whether the bathrooms are running along the front because kitchen water is still not something you’d want in your kitchen - this will be washing machine water, which will contain poo anyway, it will be food washed down the sink. It’s still not going to be pleasant.

It hasn’t gone… yet. The thing with sewers is they might never go, they might go after 2 years of being installed or it might take them 100 years to go. A little bit of it depends on who is upstream of you and what they are chucking down there. With it definitely taking waste from the kitchen, you have the potential for a blockage to be caused due to kitchen fats collecting. Usually, if there is a manhole there it’ll be a for a reason. In your case it’ll probably be because you’re midway so providing an access point to both upstream and downstream. The blockage could be two doors up and so you kitchen isn’t flooded but you will still need to provide access to water company staff as they will often work from both ends. They could be working at any time of the day or night.

Moving the pipes outside is adding bends. Bends are where toilet paper and kitchen fats collect as it’s harder for them to get round the bend. So adding bends you’re more likely to get blockages and flooding. It’s working out which is the lesser of two evils for you.

How long have you been in your house? I’m surprised this wasn’t picked up when you purchased as even thirty years ago in a previous role, I was dealing with legal procedures where people wanted to build over drains etc. and it was very clear that if there were any issues the water company are totally within their rights to dig up your conservatory floor. This was all added to title deeds. I personally would never have bought anywhere with this situation, but doesn’t help you if your deeds didn’t reflect that this took place. Although still surprised that this hadn’t come up in questions to seller when you purchased. I’m not sure what your best options are but I do think you absolutely have to go down the route of consulting the relevant water company.

Contact a groundwork company, they'll be your best bet with drains. Not builder's, they build above ground level. Groundworks below ground level.

Thank you everyone, for your replies. Lots to think about, certainly.

I think I’ll move it, as I said I’ve become used to it and from my investigations it’s lasted 20 ish years. BUT I am now thinking of brittle pipes and flushed nappies and overflow 🤢 I’ll see what Thames water says and look at groundwater companies (thanks @4FoxxSake I didn’t know that).

I’ve been here 6 years @PatsyJStone, several offers had fallen through beforehand and I was running out of time. I viewed the house only once but it’s in the catchment of a very good secondary and I had nowhere to move to next (short term accommodation). I got the keys the day before the local council cut off for applying to the school on catchment grounds. I looked around the house when I got the keys and burst in to tears but the kids got in to the school 😂