Replace manhole with t junction

Foul and surface water, private drains and public sewers, land drains and soakaways, filter drains and any other ways of getting rid of water.
pianopete
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Post: # 29724Post pianopete

Hello to all the Drain Wizards,

I would appreciate some of your wisdom thanks.

i am laying the foundations for an extension to my house. The extension floor will cover the foul/rain water sewage inspection manhole that connects to the main sewer. This is built in brick.

The BCO said it was not possible to put a double sealed cover and have an access hatch through the (wood) floor, because it would be possible to flood under floor.

The proposal is to remove the inspection manhole and put a T junction as i need to connect a rainwater pipe into the system.

The architect plan is shown at the following image:-
Image

The line to the right is going to be new plastic.
The line to the left is the outlet to the main sewer.
The new line is not quite inline with the left piece, (it was not surveyed properly). There is a slight angle and it ends up nearer the "bottom of the page"/

The new pipe work will be plastic. The existing pipes are glazed clay (about 1950)

Rodding eyes will be put at the end of the two inlet runs to allow the joint to be cleared if blocked.


My questions are:-
1) What does the "TE" mean, i heard the term testing eye but haven't a clue on this.

2) Can i use a plastic T junction and join it to the clay with flexible couplings ?

3) How can this be tested ?
The outlet is a straight run to the IC at the pavement. There is a drain gully hanging off this.
One inlet (the new plastic) is connected to two bottle gullies and a rodding eye.
The second inlet is the existing clay run to the WC and a Kitchen drain. A new rodding eye will be put at the end of the straight run.

Dave_L
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Post: # 29730Post Dave_L

I could really do with seeing the plan image Pete - nothing is showing ^
RW Gale Ltd - Civils & Surfacing Contractors based in Somerset

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pianopete
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Post: # 29732Post pianopete

Sorry about that, the pasting of images is rather problematic.

Try going straight to this link....

photo should be here

Dave_L
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Post: # 29736Post Dave_L

I'm confused - you say the line to the left is to the foul sewer? The pipework run indicated on your diagram shows it running to the right??
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Dave_L
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Post: # 29738Post Dave_L

Here's the image.....slightly bigger aswell.

Image
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pianopete
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Post: # 29746Post pianopete

hello,
yes the outlet is the left, the new pipe is to the right.

I have dug down to the pipes and have some more photos at the same website address.

I have indicated the direction of the new pipe work with a length of wood. Hope this is clearer.

Dave_L
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Post: # 29748Post Dave_L

I see, that's clearer Pete.

There is a change of direction at this point in your system - more than 90 degrees looking at your image. Any such turn would require a chamber, which is why there was one there beforehand.

You couldn't just put a tee in there, you'd be asking for trouble, plus your BCO wouldn't approve.

I fear you are going to have to carry out some pretty serious re-routing of your drainage system.

Anybody else care to comment?
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pianopete
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Joined: Fri Jul 04, 2008 5:57 pm
Location: scotland

Post: # 29749Post pianopete

hello,

the BCO approved this when the plans were drawn up. There was much discussion. I wanted to keep the chamber and have the rain water come in over the benching. The problem is that it is under the floor.

pianopete
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Joined: Fri Jul 04, 2008 5:57 pm
Location: scotland

Post: # 29753Post pianopete

Hello,
I had the BCO around specifically to talk about it this week.

I've just had a brainwave. Why can't i put an inspection hatch in as usual and bring the double sealed cover to solum level, Then i could build a "moat" around it in brick right up to floor level and include a hatch in the floor. What would the BCO say about that ?
It would save me a load of work at the WC end where i have to put in a new rodding eye.

Dave_L
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Post: # 29754Post Dave_L

It's up to your BCO in the end.

Drianage and changes of direction etc are dealth with here - Access Points
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pianopete
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Post: # 29757Post pianopete

Looking at the FAQ .......

Access points:
(Rodding eyes, Access Fittings, Inspection chambers and Manholes)

Must be installed at

* head of run
* bend or change of direction
* change in pipe diameter
* junction, unless all runs connected to junction can be rodded from another access point.

There will be rodding eyes at the end of each pipe run. So the last rule is satisfied.



Back to my original question !! What do you suggest is the best way and fittings required to put a tee in my installation ?? and how do i go about testing it ?

seanandruby
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Post: # 29763Post seanandruby

Dont know if im understanding it, but if i am right, wont you need an oblique junction and a 45% bend to get round that as it looks like you are going against the flow?
sean

Dave_L
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Post: # 29767Post Dave_L

From what I understand, flow is from right to left, the new run coming in from the right, as indicated by the wood.

Image

I still think some sort of chamber is required here, as there is a fairly severe direction change.
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seanandruby
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Post: # 29773Post seanandruby

......If the main man is okaying it and it is all roddable then i cant see a problem. But it will require a fair amount of "tweaking" with slow bends etc to get it in but it is doable. Good old flexi connecters :;):
sean

pianopete
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Location: scotland

Post: # 29774Post pianopete

Thanks for your replies..

I still unsure how to test it as i need to plug each run into the junction, but it will not be accessible.

Is there a test device that has an inflatable bung on the end of a rod ?
Otherwise i would have to take a flexi connector off and insert a bung. Has anyone got experience of doing this ??

If you think this is bad, I have just uncovered the other end. Its a quite complicated maze. I also discovered the WC connection to the pipe is broken and was leaking (cast iron to clay).
I am trying to figure out the best way for this. Will post a picture later and what i think is needed.

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