Water and Drainage search - surface into foul waste

[RJRock]

Hi all.

Have had a Water and Drainage search on a property and the result has come back as stating that the surface water drains to the foul according to the water companies records.

I asked our solicitor if this means if its permissible or not. Effectively they had no idea.

The house has been in my family since it was built in 1969. I am buying out my sister's share hence the search. I need to maintain the drainage front and back as we're on clay and receive run off from an adjacent road, also there is not a natural slope from our property to disperse surface water.

I'm doing an extension and the maintenance is part of my initial ground works. Is it permissible for this set up for surface water drainage in certain circumstances or is it under the radar until the building inspector reviews our extension works?

Any advice welcome.

 

[maltaron]

It's quite normal for surface water to go into foul drains. You will note on your water bill if you are paying for highway drainage and surface water. You get a discount if you use a soakaway (not acceptable in your case) or drain to a watercourse.

 

[jeds]

Your new extension must be drained into a soakaway. If a soakaway is not technically possible you may drain to a surface water system. (it's your responsibility to show a soakaway isn't possible) If a surface water system is not available then you may drain into a foul system.

 

[RJRock]

It's quite normal for surface water to go into foul drains. You will note on your water bill if you are paying for highway drainage and surface water. You get a discount if you use a soakaway (not acceptable in your case) or drain to a watercourse.

Interesting - I've dug out our latest bill and on the reverse (dwrcymru) it has a subtitle under need any further help:

Surface water drainage; "if none of the rainwater falling on your premises and grounds enters the public sewer, you can claim a reduction in your sewerage charges. any reduction will apply from 1 April of the year in which the claim is made."


Effectively it seems dwrcymru customers pay by default for surface water entering foul drains.

 

[luisdesign]

What you have is basically a combined drainage system. There is nothing particularly wrong with this.

The alternative you describe is to have separate foul and rainwater drainage - each system having its own underground drainage and access manholes. However, ultimately they tend to both end up dropping out into the main sewer anyway.

There are other drainage options too such as a soakaway - as already mentioned or other SUDS system

Whilst there is a hierarchy of best to worst, both of the systems you describe are permissable. When you apply for planning permission (presuming your extension is subject to it) they do actually ask how you will treat rainwater run off so it is definitely something that should be considered at an early stage.

 

[xdave]

You get a discount if you use a soakaway (not acceptable in your case) or drain to a watercourse.

Part of the runoff on my property goes to a soakaway with the rest going into a stream at the rear of the property. The stream is manmade to take water from some natural springs and to drain ground water from what used to be a flood plain 50 years ago before the river was moved through the town. I asked my water board (South West Water) if I had to pay the combined sewerage charges as I was not using their drains but they said that because they are responsible for maintaining the stream then the charge still applies.

I thought that was the end of it but could that be wrong?

 

[RJRock]

What you have is basically a combined drainage system. There is nothing particularly wrong with this.

The alternative you describe is to have separate foul and rainwater drainage - each system having its own underground drainage and access manholes. However, ultimately they tend to both end up dropping out into the main sewer anyway.

There are other drainage options too such as a soakaway - as already mentioned or other SUDS system

Whilst there is a hierarchy of best to worst, both of the systems you describe are permissible. When you apply for planning permission (presuming your extension is subject to it) they do actually ask how you will treat rainwater run off so it is definitely something that should be considered at an early stage.

Soakaways - aren't they effectively attenuators and come under surface water drainage? I have 40 year old soakaways around the house which do nothing and may have been originally connected to the drainage system anyway. Some maintenance is long overdue. Seeing as I'm paying for draining into the sewer....

 

[jeds]

You get a discount if you use a soakaway (not acceptable in your case) or drain to a watercourse.

Part of the runoff on my property goes to a soakaway with the rest going into a stream at the rear of the property. The stream is manmade to take water from some natural springs and to drain ground water from what used to be a flood plain 50 years ago before the river was moved through the town. I asked my water board (South West Water) if I had to pay the combined sewerage charges as I was not using their drains but they said that because they are responsible for maintaining the stream then the charge still applies.

I thought that was the end of it but could that be wrong?

That only applies if the watercourse is a designated 'public surface water sewer' - which is unlikely. If it is not it will be an 'ordinary water course'. OWCs are not the responsibility of the sewerage undertaker.

 

[xdave]

That only applies if the watercourse is a designated 'public surface water sewer' - which is unlikely. If it is not it will be an 'ordinary water course'. OWCs are not the responsibility of the sewerage undertaker.

Thank you for the reply. I will contact them again and this time press for why they believe the charge still applies. I'll ask them what the designation of the stream is too.

 

[maltaron]

As you are in Devon you, as I, have the misfortune of dealing with South West Water. I get the surface water discount and its a similar setup to yours. My surface water drains into the River Seaton alongside my garden, which I believe is now the responsibility of the Environment Agency. Go back to them and argue that as the surface water does not enter their foul sewer you are entitled to discount on the sewage charge.