Section 104 Essentials: adoption of a new sewer

If you’re constructing sewers or pumping stations as part of a new development, you can ask your Local Water Authority to adopt the new network under Section 104 of the Water Industry Act 1991.

During this process, you will be responsible for all construction and maintenance costs until your LWA adopts the sewer or pumping station.

The new Code for Adoption was introduced on 1 April 2020, replacing the previous ‘Sewers for Adoptions’ guidelines, which means that all new section 104 applications need to be compliant with the Design and Construction Guide published by Water UK, under this new code.

Code for Adoption recommends that developers do not start constructing any new sewers for Local Water Authorities to adopt until all parties have signed the legal Section 104 agreement. Also included is a provision for Sewerage Undertakers to adopt Sustainable Drainage Systems (SUDs) facilities.

No time to read on? Give us a call on 01268 950050 and use our 40+ years of drainage expertise to get your Section 104 application done and dusted.

Stages of a Section 104 Application 

Each Local Water Authority will have a slightly different process and range of costs for the S104 application. Make sure you check your LWA website for the latest information. Pay particular attention to application timings to avoid any unforeseen delays to your project works.

Most S104 applications follow a similar structure as shown below, but please check your LWA for specific details:

  1. Checking capacity and point of connection: a pre-planning application/conversation helps the LWA check if the existing network has enough capacity to serve your proposed development.
  2. Reviewing your design/checking compliance: before any work can begin, you’ll need to submit your plans via a S104 application form, gain your LWA’s approval and formally sign an agreement. All designs need to be in line with the Code for Adoption industry standards and contain the required information.
  3. Starting work: you’ll agree on site with your LWA any risks that could delay construction or approval, then agree your programme of works and a planned inspection timetable. You will also need to have paid all fees at this point.
  4. Inspecting your sewer: your LWA will routinely out carry out construction inspections on site, and air testing if appropriate.
  5. Starting your maintenance period: before you start a 12-month maintenance period, your LWA will inspect manholes and ask for a CCTV survey as part of the pre-maintenance inspection. You must fix any problems identified before your LWA can issue a provisional certificate of completion.
  6. Completing a final inspection: after 10-12 months of your maintenance period, the LWA will arrange a final inspection. If any problems are found, you will need to carry out remedial work. By this time, you also need to finalise all legal documents and discharge rights.
  7. Adopting your sewer: once deemed completed to a satisfactory standard, your LWA will formally sign off the site and release you from defect liability. They will then issue a vesting certificate to confirm adoption of the new sewers. From this point your LWA is responsible for maintaining the sewers.

Paperwork Required for a Section 104 Application

In order to make a S104 sewer adoption application, you will typically need to supply:

  • A developer programme, including details of construction phasing, surface water strategy and SuDs.
  • A location plan in line with your LWA’s specific requirements.
  • Longitudinal sections of the sewer and rising mains.
  • Copies of hydraulic design calculations.
  • Manhole schedules.
  • An adoptable drainage layout.

Latest Information and Charges for a Section 104 Application

Information in this article is correct as of November 2023 and sourced from the Local Water Authorities named below. Links to the most up to date information and charges for Section 104 applications in the South East can be found at: Thames Water, Anglian Water and Southern Water.

Premier Drainage Solutions – Specialists in Sewer Connection and Adoption

We are approved contractors for Thames Water, Southern Water and Anglian Water. This makes it easier for you, as we have all the paperwork an LWA needs from a drainage contractor, including a H&S Policy, Public Liability Insurance, Quality Assurance Standards, details of previous sewer adoption works, and confined-space trained personnel for entering manholes.

We can take care of your Section 104 Application from start to finish, liaising with your LWA on the paperwork and carrying out the physical connection as an approved contractor.

Contact us now on 01268 950050 or [email protected] to arrange a site visit.

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