Another one.. Gas main damaged rainwater drain?

[Tinofpeas]

Hi,

I have just been reading with interest Funkypantons thread about his gas main damaging his sewage drain. I have a similar situation whereby I have just moved into a new property and because of the typical British summer we have had, we noticed that our rain water drains were not soaking away.

We got a local company out who managed to clear 3 out of the 4 drains, however the 4th would not clear. Suspected collapased, we have now had a national company and there CCTV down there, and yes it is collapased and they suspect that the mains gas that runs directly over the drain is the cause.

Would anybody by able to advise if we should be able to get national grid to repair the drain or cover the costs?

TIA

Joanne

[bluebottle]

Re: Another one.. Gas main damaged rainwater drain?

That depends on whether National Grid or whoever laid the gas main exercised reasonable care and skill when doing so. Is the gas main one of the older cast iron mains or one of the newer PVC mains? Get National Grid to come out and take a look, but please do bear in mind that the rain we have had is abnormal and this may have caused the gas main to sink and fracture your sewage pipe. Is the pipe that has collapsed one that discharges straight into the main sewer or is it an interceptor, that is, one that feeds into another pipe that, in turn, discharges into the main sewer?

[Tinofpeas]

Re: Another one.. Gas main damaged rainwater drain?

I am unsure on the coating of the gas pipe, the house was only built 30 years ago? I'm unsure if this may give you an idea.

As for the discharge into the main sewer, again something I'm unsure of, but the gully in which the rain water falls into is around 2.2meters away from the manhole/inspection chamber, so not a lengthy stretch but an important one.

Ive emailed the complaints team at the national grid as I was unable to find another appropriate link.

Thanks

[bluebottle]

Re: Another one.. Gas main damaged rainwater drain?

Up until about the 1980s, gas boards used cast iron mains, but these were then and still are being replaced with mains made from PVC. The rainwater gully will discharge into an interceptor pipe that, then, feeds into a larger bore pipe that discharges into the main sewer. Getting National Grid to come and investigate is, probably, the best thing to do. Obviously, if there is a smell of gas, ring 0800 111 999.

[stevejay]

Re: Another one.. Gas main damaged rainwater drain?

When you contact the transporter, National Grid, Southern Gas Networks etc, ask for a manager to attend your property. You need to establish is it a gas main or service pipe (this branches off the gas main to supply a house). Ask the representative has there been a replacement in the past if so, this should be polyethelyne (PE) a lightweight plastic pipe. Check to see if you have an external meter box.

It is unlikely that the PE pipe would damage a drain however, if it is directly above the drain it may have been damaged when excavation was taking place to replace the existing older iron pipe. Keep the DVD of the CCTV as this will be vital evidence in the future.

Let the gas company give there version in writing.