Additional Extension Over Public Sewer - 1st One Has No Build Over Agreement

kittykatkat

We bought a house with a rear extension that was built over a private sewer that became adopted by the water company as it is shared by a neighbour. The extension is decades old, so was private at the time, and the seller paid for an indemnity policy for any issues with it.

So here is the query. We are thinking, in years to come, we may decide to extend the house further, and that extension would also have to go over the same sewer. Obviously in doing that we'd have to get a build over agreement first, or re-route the sewer at our expense, but in doing this we would have to contact the water company and therefore alert them to the existing extension and invalidate the indemnity policy on that. What would be the best way to tackle this, if we go down that path?

Has such a situation ever arisen before? I know this is a fairly recent problem due to the mass adoption of shared sewers. Personally I think the adoption was ill thought out - there should have been some sort of written "amnesty" on existing extensions that were built to the laws of the time - they were private sewers and homeowners could build over them as much as they wanted to, within building regs.

kittykatkat

No ideas anyone? (I appreciate it's a rare scenario although it will get much more common over the coming years when people want to extend over what are now public sewers).

quotememiserable

I think if the policy is invalidated it will be whether you talk to the water company or not. You'd need to read the policy to find out if this situation invalidates it.
As for your water company, they're not going to worry about an existing situation, but if your new extenstion covers more of the sewer than the current arrangement, they might not be keen on that. You need to get hold of the appropriate asset manager (they usually cover geographic reasons, but you don't say which company) and talk about it. How deep is the pipe? Its probably fairly shallow and diverting it shouldn't be a great extra expense if your in there digging footings already.

kittykatkat

quotememiserable wrote: »

I think if the policy is invalidated it will be whether you talk to the water company or not. You'd need to read the policy to find out if this situation invalidates it.
As for your water company, they're not going to worry about an existing situation, but if your new extenstion covers more of the sewer than the current arrangement, they might not be keen on that. You need to get hold of the appropriate asset manager (they usually cover geographic reasons, but you don't say which company) and talk about it. How deep is the pipe? Its probably fairly shallow and diverting it shouldn't be a great extra expense if your in there digging footings already.

The additional extension would roughly double the current one and together they'd pretty much cover the width of our plot, so all the sewer on our land. However the downstairs of the new extension would mainly be an integral garage so the manhole would be easy access and wouldn't need moving from where it is now on the drive.

I'd say it's about 2ft deep, if that. The problem with diverting it would be we'd not be able to keep it 3+ metres clear of the new and existing walls unless we also dug up on to our neighbour's garden too!

quotememiserable

Having the manhole inside the garage might be better than having it covered over, but from the companies point of view its still inaccessible, plus if the pipe needs repairs its under your property. I'd still say that if you do want to do this, you need to track down their asset manager.

Bsnimunf

kittykatkat wrote: »

We bought a house with a rear extension that was built over a private sewer that became adopted by the water company as it is shared by a neighbour. The extension is decades old, so was private at the time, and the seller paid for an indemnity policy for any issues with it.

So here is the query. We are thinking, in years to come, we may decide to extend the house further, and that extension would also have to go over the same sewer. Obviously in doing that we'd have to get a build over agreement first, or re-route the sewer at our expense, but in doing this we would have to contact the water company and therefore alert them to the existing extension and invalidate the indemnity policy on that. What would be the best way to tackle this, if we go down that path?

Has such a situation ever arisen before? I know this is a fairly recent problem due to the mass adoption of shared sewers. Personally I think the adoption was ill thought out - there should have been some sort of written "amnesty" on existing extensions that were built to the laws of the time - they were private sewers and homeowners could build over them as much as they wanted to, within building regs.

I think the indemnity policy would still cover the existing extension but not the sewer itself, alerting the sewage company would not result in invalidation of the policy. I have experience of a simaler situation where a conservatory was built over a private sewer which then became a transferred sewer. The drain then collapsed. The insurance company paid to remove the conservatory then the sewage undertaker repaired the sewer. Not sure if the conservatory went back up after. Having worked for the local water company I strongly recommend not building over drains or sewers and dont buy houses built over drains or sewers, ive seen some really nasty stuff i.e repeated incidents of sewage flooding from hidden MHs under tiles in people kitchens etc, all because their trampy neighbours cant stop flushing face wipes down the toilet. Also all drains will collapse eventualy. Its not nice telling people they are going to have sewerage repeatedly flooding their garden whilst we wait for their insurance company to take down their extension.