Have You Obtained Your Local Authorty Water Boards Approval?

Hopefully this issue would have been picked up during your Building Design Agents Full Plans design and submission to the Building Control Dept. where the Local Authority would have red flagged any new building works within 3M of a main sewer.

However, this is not always 100% effective and extension schemes can slip through.

Many main sewers are exposed during the excavation process and come as a complete shock with the added delays and expenses while the situation or revised design is resolved.

You may want to independently check with your local Water Authority that your scheme will not be near a main sewer.  Most have a formal application & fee process for this service.

As a guide all pre-1936 private shared drains or sewers will come under the local water boards jurisdiction & most will require their written approval if you are building over or within 3M of a controlled drain.  Soon, all shared private drains will be treated as a main sewer. Most local Water Authorities require a fairly high fee for giving their consent.