Extension - public sewer - advice

17 Sep 2012
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United Kingdom

I'm a few weeks into a self-build extension project. I have a certificate of lawful development and full plans approval. I've dug the trenches (90cm) , had them inspected and poured the foundations. The dig was in undisturbed sand .

I have now had a letter from Thames Water saying that they believe my works are within 3 meters of or over a public sewer, I need to send them £343 for a check and must not start work (A bit late for that).

The letter does not give any indication as to why they believe there is a sewer present. I am not aware of any manholes on our properties or in neighbouring properties that would reveal one is present. I did have a survey done when I bought the property, it shows a public sewer but in the road at the front and not crossing our property.

I intend to call them tomorrow, any advice?
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Was the water company not consulted by the council during the CLD application process? If you are unsure there should be a 'consultation response' document or similar if you look at the online application documents.
Thanks for that suggestion, If only the councils planning site wasn't down I'd be able to check :( Hopefully it will be up in the morning.
I spoke to Thames Water. They told me that it is a standard letter and they actually have no idea where their sewers are (despite stating the opposite).

I am going to send a letter and tell them to foxtrot oscar
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I spoke to the guy at my local council this morning who was very helpful (and for amusement called Mr Plummer).

He checked the records and thinks that they are looking for any sewer within three meters of the boundary to trigger their letters.


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