Sewer advice

[VogonPoet]

*I'm posting this to the Building Regs subforum as I've seen quite a few posts about building next to or over sewers, I'm hoping someone here will know enough about working with the water companies to answer this one. If it would be better off in another area please let me know*

Hello all

I'd be grateful for some advice about a shared sewer running beneath my property. Some background; it is a semi-detached house built around 1960 by the local authority. Ground levels vary around the property so it is effectively built on a hump, the level drops a couple of feet or so to the road at the front and drops more towards the rear. It appears there was a shed/garage at one point, only the concrete base remains. There is a driveway running past the house down to the garage base, the first section of the driveway is half concrete, the other half is paving slabs. The slope down towards the garage is all concrete. Some time in mid-90s the LA added small brick extensions to the rear of all similar houses in the area.

I've seen the plans for the area and there is a pretty big shared rainwater/foul sewer running under the road, then under my driveway (beneath the concrete side) to a manhole, it then turns a right-angle and heads across my land onto my next door neighbours property.

There seems to have been some movement of the land towards the rear of my house as the garage base is cracked into four large pieces. There are also cracks to the concrete of the sloped driveway at the rear and it appears to have slipped down a little, the cracks run into the surround for the manhole cover. I can't see any evidence of subsidence in the house or extension which is a relief.

I can think of a couple of explanations for the cracks:

a ) There is a problem with the sewer that has let water undermine the ground supporting the concrete in those areas.

b ) When they put in the footings for the extension they disturbed the ground enough to make the slope crack and slip. The garage base cracking is due to poor construction and is unrelated to the driveway issue.

Do you think I should call out the water company to inspect the shared sewer and the cracking above it? If I do and they find a problem with the sewer, or are unhappy with the cracking around the manhole, who would pay to have it fixed (me, them, half-and-half)? Could they compel me to pay for it to be fixed?

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[^woody^]

Or it could be normal ground movement. Cracks to flaunching around a manhole are common too.

Normally, if your land moves then it's your responsibility. That's why we have insurance.

You've drawn that sewer to be what looks like close to 1m wide. Is it?

 

[KenGMac]

Have a look at this, it may assist?

www.ccwater.org.uk/waterissues/.../privatesewersandlateraldrains

There are a lot of other sites where information can obtained as regards drains and Sewers.

From experience, the local to you water board will probably prevaricate and deny that their Sewer is not at fault?

There is a fall back position? contact your insurer? BUT.

If you contact your Insurer, and you make an insurance Claim, your premium will rise next year, there is an excess that will apply if the claim for a defective drain is valid, the up-Side of an insurance claim is that the insurer will probably instruct a CCTV Survey of the Sewer.

But if you do make a claim in effect your insurer should be there to assist other opinions as regards insurers will be forthcoming.

Ken

 

[VogonPoet]

Or it could be normal ground movement. Cracks to flaunching around a manhole are common too.

Normally, if your land moves then it's your responsibility. That's why we have insurance.

You've drawn that sewer to be what looks like close to 1m wide. Is it?

I don't know how wide the sewer is, the drawing is not to scale - it just shows the route it takes. The manhole is around 60cm in diameter.

I agree it'd normally be my responsibility to correct a cracked drive but if damage to a shared sewer is the cause of the movement then surely the water company bears responsibility too?

The water company website has the usual section about which parts of the sewer they are responsible for and who to contact if the public sewer is blocked and flooding. There is nothing about the extent of their responsibility if the sewer is damaged/leaking/collapsing and this is having a knock-on effect on surrounding structures.