Blocked Drain Problem

[Blofeld72]

Hello, I live in a terraced house, No. 48 on the map image.

At the rear we all have a kitchen extension of varying sizes and a small yard, maybe 15' x 10'. We each have a private drain that runs into a public sewer that runs down the back lane that separates our properties to the ones to the rear of us.

After my boy failed yet again to flush the loo after a No 2 I flushed it myself and it didn't go down, I had a poke about in the pan with the loo brush (as you do) and it seemed to go down, I thought it was odd seeing as he's 8 and I've never managed to block it that way myself! But didn't think much of it until tonight when the same thing happened.

I have a single manhole in my yard and I'm not sure if it's draining correctly or there is a problem.

There was about and inch or so of water that had backed up against the end, at the end of the run there is a vertical hole going straight down and another that goes down at about 45 degrees, the entrance to the 45 deg one is about an inch or so higher than the main pipe invert. It's frankly about 5 years since I looked down this MH so I don't know if it has always been like this or not. I had a bit of a poke around and have taken a couple of pics. Whilst I poked around a bit I noticed a clay disc (see the photos) seemingly sitting vertically in the vertical hole which I fished out and took a pic of, its about 6" in diameter and made of clay.

Is this a normal drain or is there a problem and surely this disc should not be sitting in the pipe? Should it be sitting horizontally across the vertical pipe or what?

I'm sorry for the rambling.

Map

Drain run







disc thingy

 

[John D v2.0]

that's one of those funny traps they used to put in to stop funny smells coming back from the main drains.
They've been discredited but it works in the same way as your kitchen sink trap, just holds a little water in normal situation.
They also provide an access above to rod downstream in case of blockage, but this is normally capped by that little cover.
So everything is normal and the cover it just for the rodding point.

regarding the loo issue, just get someone to flush the loo when you are looking in the manhole. If the water doesn't flow through smoothly in one go after a few seconds, then you may have a blockage upstream.

 

[Newboy]

It's a victorian interceptor.

The clay disc should be fitted in the upper outlet.

The water level in the trap looks OK.

 

[^woody^]

What's that unlawful connection half way up the manhole?

 

[Ian H]

Your interceptor is broken but your problem with the toilet it further up.

Does anything else join your soil pipe lower down that the toilet branch?

 

[Nige F]

The clay disc looks like the top off a bowling ball - leave it out Maybe the higher connection is the air vent inlet ?

 

[Newboy]

Maybe the higher connection is the air vent inlet ?

Optimist!