Sewer diversion to enable rear extension

Project Overview

Premier Drainage Solutions was commissioned to deliver a minor sewer diversion to facilitate a rear home extension, after the homeowner discovered an unexpected 225mm foul water sewer running diagonally across the garden—directly in the path of the planned new foundations. The work involved the relocation of a 1200mm pre-cast concrete manhole and the diversion of 10.5m of foul sewer pipe to clear the proposed build zone.

Scope of Works

• Excavation and Removal of Existing Pipework

  Upon mobilisation, our team excavated and removed the existing 5m section of 225mm clay pipe, along with a pre-cast concrete manhole that lay within the future footprint of the new extension.

• Construction of New Sewer Line and Manhole

  A new section of foul sewer was installed using heavy-duty clay pipe, rerouted around the build area and terminating in a newly constructed 1200mm pre-cast manhole. This ensured full compliance with Thames Water standards for adoptable sewers.

• Fast Turnaround and Coordination

  With no licence required for this minor diversion, we mobilised to site within two weeks of order placement. We worked collaboratively with both the homeowner and contractor to meet build timelines and minimise any delays to the wider extension works.

• Thames Water Liaison

  Our team ensured a seamless inspection and sign-off by Thames Water, coordinating directly with the authority on behalf of the client to validate all installation works.

Key Challenges

• Tight Residential Footprint

  Working in a confined rear garden space required careful material handling, compact excavation, and clear communication with the homeowner throughout the build.

• Time-Sensitive Build Programme
  

  With the construction timeline already under way, our ability to respond quickly and complete within days allowed the extension to proceed without delay