Strange toilet blockage issue

[blueagle78]

I'm so glad and relieved its all sorted now. Thames Water sent some third-party guys out to find out the cause of the blockage. These chaps were very generous and they decided to un-block the pipes even though it wasn't Thames Water's issue. I've updated the previous picture so you could see where the blockage was. They advised me blockage was caused by oil, grease and wet wipes (this is shocking!).
However, they advised me my property is the only one that's using that part of the chamber which I'm quite baffled about. Because if you look at the below picture you'll see its got quite a few connections coming into it. I took the picture while facing the house.
https://picasaweb.google.com/lh/photo/zMcUl-AG39BP1HkQZi3tTdMTjNZETYmyPJy0liipFm0?feat=directlink

Hugh my property was individually built in 1985 and yes its on slope. I was under the impression houses on the left hand side (while facing the house) might be draining in this one because they're on a slightly higher ground level than mine.

 

[Space cat]

However, they advised me my property is the only one that's using that part of the chamber which I'm quite baffled about. Because if you look at the below picture you'll see its got quite a few connections coming into it.

That looks like a standard, preformed chamber with five inlets and one outlet. Unused inlets are blocked off. While you've got a good view with no blockages, why not go round your toilets and drain gulleys. chuck some water into each and see where it goes. That way, if you ever have to rod upstream towards a blocked gulley, you'll know which branch goes where.

 

[blueagle78]

While you've got a good view with no blockages, why not go round your toilets and drain gulleys. chuck some water into each and see where it goes.

Would you please explain this a bit more? So if I flush each toilet, I'm guessing water would come to this chamber. Is that what you want me to confirm? Sorry if I sound dumb but as I've said before I don't know much about plumbing but I'm curious and want to learn so any guidance would be really appreciated.

 

[Space cat]

So if I flush each toilet, I'm guessing water would come to this chamber. Is that what you want me to confirm?

That's the general idea. You flush each toilet in turn and see through which branch the water enters that chamber. Then you do the same with your drain gulleys by pouring a bucket of water into each one.

You might find that some (or even all) of them share a common inlet, in which case you should look upstream for other chambers and repeat the process. Hopefully there won't be any toilets or gulleys that don't ultimately empty into that chamber.

The idea is to map out your drainage system as best you can. Blockages are easier to deal with if you know where all the pipes go.

 

[blueagle78]

Space cat that certainly makes sense and that's something I wanted to do. As I only moved in this house few months ago, still learning about it so it'll be good to have better understanding of the drainage system.
THANKS a lot for this great tip.

 

[Space cat]

You're welcome.

 

[Hugh Jaleak]

Looking at that pic, the two branches on the right hand side are in use, you can see the water running out from them. The 2 left hand branches may not be used, you should be able to see the blanking plugs fitted into the sockets.

An individually built property is more likely to have an independant drainage system, to connect another property at a later date is not unheard of, but involves legal procedures to get permissions to excavate and install the drain through the original property to the existing sewer. If the builder is constructing several units at the same time then he is likely to common all the units into one drain. One connection to public sewer and one connection charge payable!

To add to Spacecat's good advice, drain testing dyes are available if it helps avoid confusion as to what goes where.

 

[dal5band]

If it is not flowing it is blocked - don't ignore the obvious.

So it WAS a blockage after all !!!!

 

[blueagle78]

The same "main drainage" is blocked again. Noticed it yesterday when cloak room started smelling. The first thing I did was to remove the lid of that chamber and I saw what I didn't want to see. I'm thinking of buying the drain rods today and would try to fix it myself. But I'm worried why it has happened again within 2 months.
As for rods which ones should I go for? I'm confused between these two:

http://www.screwfix.com/p/bailey-9m-drain-rod-set/14843
http://www.toolstation.com/shop/Hand+Tools/Drain+Rods/Expert+Drain+Rod+Set+7+Piece/d10/sd2916/p37178

I would once again really appreciate any advise given by you "subject matter experts".

 

[Nige F]

Don`t waste your money on rods - that blockage is beyond their scope . Get the Water co. back - even if it isn`t their responsibility , which I doubt . You`ll get it jetted anyway and then pay less than *****rod . And stop putting wipes down

 

[blueagle78]

Thames Water turned up yesterday while I wasn't at home and unblocked the drainage. I don't know what it was this time because they didn't call me before they came out.
While I was in B&Q yesterday, I saw this drainage unblocker liquid (I believe it was sulphuric acid). Shall I get one of those and pour it in the main chamber where I see the blockage so whatever is remaining in the pipes would get cleared out?

 

[dal5band]

There may be some inherant problem - damaged drain, bad layout, or root or just a joint lip sticking up. This starts the blockage. A video survey will show this up.
Otherwise it's usage - check your houshold is not throwing things down the drain that they shouldn't.

 

[blueagle78]

dal5band thanks for your response. Its really appreciated.
I moved in this house last year in August and the first blockage was experienced in April/May time. But now we had a second blockage. As far as I know nothing as change with regards to usage. Could it be roots of nearby trees causing this?
Do you know how much I'll roughly be paying if I go for video survey?
Thanks

 

[HERTS P&D]

If you were local to me, I would charge you £199. With a DVD, you would have your own 'dirty movie'.

Andy

 

[Nige F]

Thames Water turned up yesterday while I wasn't at home and unblocked the drainage. I don't know what it was this time because they didn't call me before they came out.
While I was in B&Q yesterday, I saw this drainage unblocker liquid (I believe it was sulphuric acid). Shall I get one of those and pour it in the main chamber where I see the blockage so whatever is remaining in the pipes would get cleared out?

So TW cleared it again F.O.C - then it`s probably their responsibility . Don`t waste your time with drain cleaning acid or your money on CCTV`s . After enough clearouts TW will have to dig and relay the sewer .