So how is the "blockage" manifesting itself? Gulley full and water pouring out? Significant splashing through the grate that would wet shoes if you were sat at the bistro table??

Pumped water coming from a washing machine then falling 3-4 metres into a thin copper pipe could well come out pretty fast

I do understand the speed of the water exit, but I believe the issue is that the trap blocks. Don't know why because for the ten years that we lived there, it never happened.

However, when I have been called, the gully is full of grey water. When more water is added, it overflows onto the gravel area. When I have flushed it, if flows just fine.

Last week, when this current issue raised its head again, having jet washed around four weeks ago, when I got there, the water level was as it should be, probably at the level of the trap bend. No tap water available so could not jet wash, but did use a snake both up and down stream followed by two buckets of water. The bucket flow rate was considerably greater than the copper exit pipe flow, and the level did not get anywhere near the top of the gully. it washed thorough without any problem.

Totally agree. In the past, there were only the two of us, and generally only two tenants. We now have a family of four two teenage girls and Dad who is a builder. So more cooking and certainly more use of the washing machine.

Posted By: Mike1Here's a demo that should explain it; any smells would be coming up from the sewer:

https://youtube.com/watch?&v=1PHQoR2PhYo

Ahh, thanks for that. It looks very useful.

You want to see what is there now not after you have done any sort of further cleaning so just a bucket of water before the survey starts.

Posted By: Rexhe wants a full-on health and safety check-box filled out

Time to be creative.
Risk of subsidence = high.
Risk of unexploded ordnance = high.
Risk of toxic chemical drain cleaners = high.
Risk of RSI from filing out check boxes = high.

My understanding of the law is that in addition to any clauses in your lease that give right to enter for the purpose of maintenance, the law provides the right of access to a neighbours property without permission to do essential maintenance. This would include and professionals you employ to carry out the work. So to (probably and hopefully) stop this nonsense tell the neighbour that under your rights granted in the lease and also within the law you will lawfully enter the property to do essential work on the drains and that he can not obstruct this access. Further he should take legal advice and as Jonti says employ a risk assessment engineer.

Essentially call his bluff and give him more trouble (and expense) than he is causing you!

We had a neighbour dispute that started over something similarly small and ended up very unpleasant with solicitors involved. People get very defensive over their homes and castles. Once trust is gone, the only long-term resolution is for one party to move out (us).

In this case the neighbour has been putting up with drain overflows into their garden for some years iirc the previous posts and so probably has lost confidence in the OP's command of the situation. They are likely worried about what further damage might be done by unknown workmen in their garden. They have considerable leverage being resident when the OP is not, they can drive out the tenant or find other expensive problems.

Rather than escalation it might be better to rebuild some trust, acknowledge they are obviously unhappy, offer them to choose a drain company, go with whatever fix is recommended. Might cost a few £k but that's cheaper than having to sell up.

The water in the P trap sits all night at winter temperatures. If you leave washing up sitting in the sink overnight in cold water you can expect floating chunks of grease and the P trap is no different, build-up is inevitable. Modern drains do not have P traps and gullies for this reason. Seriously consider updating it, but offer that as a possibility to the neighbours rather than announcing that's what you have unilaterally decided to do.

As Will says this has been going on a long time so you need to accept that the GF occupier is reasonable in getting ars*y. Probably best to avoid antagonising them any further and look to build bridges.

If the trap is anything like some of ours you can put your hand round the bottom of the gully and feel the "weir" on the outlet. If there's anything blocking or restricting it you'll be able to feel it.

Gentlemen,

I was being somewhat cynical regarding the risk assessment, but it would not surprise me. And I do agree about it getting out of hand and becoming a 'neighbour dispute.' I would try to diffuse before getting to that stage. And I do agree that he is rightly annoyed; if it was my property, I would feel that same.

What does not make sense is that this situation has only arisen with the current tenants; I don't recall any issues with previous tenants and when we lived there. So can only assume it is whatever they put sown the kitchen sink.

Agreed, the gully is cracked but I believe it has always been like that; I certainly have never repaired it.

Have a guy coming later this week to do a CCTV survey and I will use some caustic soda to hopefully, clear any gunk.

Given that the trap is to prevent sewerage smells, in this case, coming into the garden, what options are there if the trap has to be replaced? Surely only another P trap?

Is there an option to direct the waste water into an elbow directly into the sewer main and have a sealed top to prevent smells emanating?

Posted By: Rexwhat options are there if the trap has to be replaced? Surely only another P trap?

A few suggestions the posts above:

Me: replace the U-bend with a rest bend & regular pipe

djh: The waste pipe could discharge straight into the sewer through a sealed connection with a normal rest bend instead of a U-bend

Peter_in_Hungary: Replace the trap with a standard elbow with a short up-stand pipe to ground level to take the kitchen outflow.

WilllnAberdeen: Modern drains do not have P traps and gullies for this reason. Seriously consider updating it

The pic on the previous page shows
1) the downstairs kitchen drains x2 into their gully
2) Rex's gully
3) a third drain or downpipe at the very top of the pic behind the jetwasher

How does that third drain get into the sewer, connected to Rex's gully? Source of blockages?
Or to a different system?

@ WiA Same pic; Between Rex's gully and the "third drain" your 2 & 3 there appears to be a grey-ish rectangular area, is that a metal cover, I can't make it out on my screen.

Gentelemen,

As usual, many thanks for your comments and thoughts.

To be clear on the photo, the gully under the table is the g/f kitchen waste, around 50 cm from the inspection chamber cover. Mine is the one with the red arrow.

Obviously, my waste pipe comes from above, but is enclosed in a box in the g/f kitchen, then presumably, has an elbow to go through the wall. We bought the maisonette around 1996 and it has always been like this. As for the rinky-dinky drainage and cracked gully, again, I have never done any maintenance as it was not necessary.

Both drain into the Y pipe as showing in another photo, which in turn drops into the main sewer pipe, about one meter away and at least 1.5m deep. It is a very large inspection chamber that has the main sewer pipe from the eight maisonettes.

Given the mine outlet is copper and the g/f is plastic, I can only assume that mine is the original from around 1965 and the g/f was redone at some point when previous owners renewed the kitchen. But what do I know?

Tomorrows CCTV will reveal all!!!

As I have written previously, many thanks for all the input. thought I was starting with a simple question; never thought it would expand with so much interest.

To address the above; some time before we bought the f/f maisonette around 1996, a previous owner of the g/g flat had a kitchen make over, and replaced the kitchen outlet with plastic. That plastic, now exposed to UV for around 3 years, is very dirty and most likely somewhat brittle and certainly discoloured. The apparent 'tide-line' is in fact a mesh they have over the gully to prevent leaves entering. Out outlet is within the gully, theirs is in fact above.

Ha the CCTV survey, which must have been the best earning job he has done for some time. All over in around 2 minutes at a cost of £100! The result, up to the trap, absolutely clear; nothing hanging, no roots, no collapse, as I suspected.

His advice was for further blockages in the trap itself, wither blast with a jet wash or even simpler, by a cheap plunger and give it a good whack from the gully side. As for replacing, he thinks that would be a complete waste of time and money since there is no reason to replace.

Will give the mpg to the g/f, tell him that my duty as a landlord is to provide all the necessary facilities in working order and any future blockages, he can handle with out tenants directly.

As a bye-the-bye, having given the g/f the name of the surveyor, he did a Google search, found him and phoned. Don't know what he asked but my contractor expressed annoyance as I was his customer.

I am sure this will not be the end of the g/f complaints. He did ask for and I'm sure will request again, a full written survey. I will suggest he asks the surveyor directly, who will refuse.