The sewer adoption procedure is the process by which new private sewers on a development site become vested in the local sewerage undertaker for long-term maintenance, in Greater London usually Thames Water. The procedure is governed by the Water Industry Act 1991, primarily through section 104 adoption agreements, supported by the Sewers for Adoption design code now incorporated into the Code for Adoption. The process includes design review, bond posting, construction inspection, CCTV survey, water testing and final vesting. Practical implications for developers across London include the need to follow approved materials, gradients and access provisions from the outset, with significant cost implications if works fail final adoption inspection. Homeowners on new developments should confirm that the section 104 process is complete or progressing on programme, as unadopted sewers remain a shared private liability.
Sewer adoption procedure
Process by which new private sewers are vested in the local sewerage undertaker.
