What is a Section 104 sewer adoption agreement?

A Section 104 sewer adoption application must be made before your drainage contractor can begin the construction of a new sewer, so that the local sewerage authority will agree to adopt the newly constructed private sewer (or pumping station) once works have been completed. This means that they will maintain it at their own expense going forwards.

When you make a Section 104 application, you must provide detailed information about the design and construction of the new sewer, and how it connects to the public sewer. The sewerage authority will need this to check that the works will be carried out in accordance with Sewerage Sector Guidance (SSG – which replaced ‘Sewers for Adoption’ in April 2020).

Save time and money: get S104 right first time

The easiest way to do a Section 104 application is to choose a drainage contractor who will take care of it as part of their service. They will already know how to produce a compliant plan and the process will be as smooth as possible – saving you time, money and effort.

Typically, costs for a Section 104 sewer adoption application include an amount to cover technical and vetting services, legal fees, and a security deposit. Currently, these are as follows for the sewerage authorities we deal with in Essex, Suffolk, Hertfordshire, Kent, Cambridgeshire and London:

Thames Water:

  • £1,000 application fee for S104 
  • 2.5% of construction cost
  • £850 legal fee (adoption agreement)
  • £750 easement fee (to formalise access rights)
  • Security deposit – either £5,000 or 10% of the construction cost estimate

Note: prices accurate at the time of writing (May 2020)

Anglian Water: 

  • Application fees for Section 104 vary by development size:
Size of development Foul only  Surface water only Foul and surface water 
Up to 50 plots £500£500£500
51-100 plots £1,000£1,500£3,500
100 plus plots £1,500£5,000£7,000
  • 2.5% of estimated construction cost (minimum charge of £510)
  • Surety – 10% of estimated construction cost (minimum charge £5,000)
  • £361 for the legal agreement (amendments charged at £120 per hour)
  • £179 CCTV assessment
  • £217 repeat vetting fee (if required)

Note: prices accurate at the time of writing (May 2020)

Southern Water:

  • S104 application fee of £515
  • Inspection fee of 2.5% of the construction value
  • £400 legal fee
  • Bond of 10% of the construction value

Note: prices accurate at the time of writing (May 2020)

So what information is required for an application? Obviously the form includes the basics of the site, the developer, and any other parties to the Section 104 agreement, as well as relevant planning conditions, the number of properties, first occupancy date, and other such standard detail. 

Making an S104 sewer adoption application

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

  • A developer programme, including details of construction phasing and surface water strategy, amongst other things
  • A location plan. There are specific requirements for this, which dictate scale and size, as well as elements such as surrounding road names, how the boundary of the development is marked, and the colours used to indicate foul sewers, surface water sewers, and sewer easement
  • Longitudinal sections of the sewer and rising mains
  • Copies of hydraulic design calculations
  • Manhole schedules
  • Typical construction details
  • An adoptable drainage layout

You will find that there may be slight differences in Section 104 application requirements depending on where your site is located, so it’s worth checking with the specific sewerage authority in question – though, of course, if you’re using a drainage contractor with experience in that part of the country, they will take care of all this for you. 

To ask us more about how Section 104 sewer adoptions work, and benefit from our free professional advice on your drainage works, call us on 01268 950050 or send us an email to [email protected]

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