Regulations and legislation around drainage and sewage systems in the UK are tight and must be adhered to.
Anyone involved with construction and engineering will be aware of general procedures around obtaining planning permissions, but it can become significantly more complicated as far as drainage and sewerage are concerned, due to ownership of the drain.
Some properties own private sewers, but generally speaking, public sewers are owned by sewerage undertakers and water and sewerage service providers. Their permission must be gained before any development work is undertaken on or around the sewer they own – and this applies to anything from a new driveway to an extension of a roof.
The potential risks of flooding and blockages must be considered in line with the likes of gradients and gully positions, so it is often not as straightforward as getting basic planning permission.