Flooded gully drain + sewer waste

13 Jan 2022
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United Kingdom
Hi all,
Looking for some advise and guidance.

We have what I am told is a gully drain that runs along side my house (on my property).

There is a square man hole cover on it, that drops into a 5ft deep concrete square space. At the bottom of this space you can see a gully/drain that is fed by rain water from guttering. All good.

Twice this year this gully has become blocked and the space fills with up to 2 feet of water.

However, this water on both occasions contains sewer waste. This time alot of it, no way its all from our house
:) see attached for image

I can't see how or where is gully would be connected to the sewer system.
My sewer man hole is about 10m away and not showing any signs of blockage.

Thames Water were called out first time (although water and waste had cleared by time they arrived) and said nothing to do with them as it's a gully not a sewer pipe.

Now it's happened again.

Not sure...
1. Who's responsibility it is.
2. How to fix it.

I've called Thames Water again but 48hr response time, so waiting patiently.

Previous occurrence I unblocked myself but this time nothing seems to be doing the trick.

Gully also runs parallel to my basement into which this flood seeps.

Any help appreciated.

Apologies if wrong terminogy was used.



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It's got to be backing up from TWA's main sewer hasn't it

TW arrived this morning.
The drain gully that I showed before is a rain/grey water gully.

Further along (not known to me and buried) TW found another manhole or an IC chamber I think it's called. This is gathering rain/gray water and sewer waste inputs.
This was full of stones/pebbles that was blocking 95% of the inlet pipe. This then blocks all water/waste back up and back.

So hopefully I just need to clear out the IC chamber now. As it's on private property TW won't touch it.
Maybe some building works nearby, stuff does get in the system through carelessness, worth trying to identify the source pipe when you clear it, in case it's ongoing. Would be interesting to learn the outcome.

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It's was pebbles, stones and some silt all built up blocking the flow.

Pebbles/stones same as the ones near the man hole covers. I would say the old man hole covers were not fully sealed and let in some debris over the years.

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