Mains leak - possible damager to foundations?

[fabgav]

Hi all,
I've had another mains water leak at the back corner of my property.
I say another because it was fixed once whilst I have lived here, and there were several 'dig' holes along the back which I always suspected where for leaks.

Anyway, the problem is the water is running into a near by man hole cover and one at the front of the property, but along the back at the party wall I have a big hole where I had gas mains moved.

This was full of water, the water was running through the old gas supply pipe and I found an old water supply pipe, also running with water.

All the soil/clay in this hole is now very soft and if you knock it it sounds hollow.

What worries me is this is about .6m down from surface and it is along the whole back of my house, and the side.

Is there any chance this is going to cause problems with sinking later on?
I plan on putting raised deck along the back, but I don't want to if I can going to have to dig everything up in a few months/years

Picture Title

• fabgav
• 16 Apr 2013
• 1

Picture Title

• fabgav
• 16 Apr 2013
• 1

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• fabgav
• 16 Apr 2013
• 1

Untitled

• fabgav
• 16 Apr 2013
• 1

 

[dann09]

It's difficult to figure out the pics - esp whats relating to what.

Essentially, you seem to have a leak on the blue mdpe water service - typically, the mdpe should be run in one single piece from the property boundary/extn. stop-tap to the internal stop-tap, in min. 25mm ( best 32mm) diameters.

You seem to have a fitting (s) on the service - perhaps it's leaking?

The Regs req a min depth of 750mm.

Are you certain that the service is leaking, and not the no-hub fitting on the drainage?

FWIW: how do you know that the "gas" pipe is redundant? If it is, then, if posssible, remove it back to the house installation and plug or cap off if it's connected to anything.

 

[fabgav]

Hi. Yes sorry the pics are a bit naff.
yes def old gas as I had it moved so that could come oit.
The mains runs into. Front of boundary along side of house across back and to my external stop ta. So all mains pipes in my boundary are still water board property, where the black tarmac is I think there is a new join and the run along back has been replaced. They are now replacing the side run so still leavong a join under the tarmac.

Sorry reply on phone hence poor spelling

 

[dann09]

I'm still a bit bewildered as to whats running where and why.

However, any constant leak will undermine any structure in time.

You must have the new supply at the correct depth in an open trench with the water under pressure to determine if all is now well. There are a number of simple ways to test for leaks, but the best test is a simple eye ball.

 

[fabgav]

Well, the plot thickens,
I t now have a length of lead, connected to plastic, back to lead, then back to plastic and then onto external lead stop tap.

I have read that if my external stop tap is within my boundaries then the supply company are responsible for the pipes upto that stop tap, including those that lay within my boundaries.

Can any confirm this>?

http://www.stwater.co.uk/upload/pdf/8175_STW_Repairing_Leaks_20070213102020.pdf

In the FAQ - What part of the water supply pipe am I legally responsible for?

Is this an out of date file or what? because today's contractors stated that it was private pipes.
(The main stop tap from mains in street is on the footpath about 60meters from my house which is row of 4 and also supplies 2 semis either side of our terrace

I asked if they would change the stop tap while water was off and they said they don't bother fitting stop taps now as the internal is enough! so they took the lead tap and fitted a blue plastic T junction.

 

[dann09]

Who is actually digging out and making these discoveries? Who are "todays contractors"? You must have an external and an internal stop-tap.

S&T water state quite clearly who is responsible for what - that pamphlet is dated 2009 - any doubts phone them.

What supplies four properties?
If you are indeed on a row supply, then read the pamphlet, it tells you who is responsible for what.

 

[fabgav]

Well it seems they are responsiable from mains to stop tap at the footpath some 40m away
So the pipe that is leaking is mine....well, mine and the other 5 homes it supplies but anyway it does beg the question when they felt they were allowed to keep the lead they took out

I am considering replacing it now from my front gate to the other end which is where there was a stop tap.

Any ideas on cost of this? the pipe is cheap cheap but the fittings from lead to MDPF?

Also is this a diy job?