Sewer Diversions

Under Section 185 of the Water Industry Act 1991, a builder or developer can request that a public sewer is altered, diverted or removed to allow a site to be developed.

Where a public sewer crosses a site, a developer can submit a request to us to undertake a reasonable diversion of it. On occasion, we will let a developer do the work with our inspector monitoring the works. All the costs involved are payable by the developer.

If you would like to undertake an alteration or diversion to the public sewer network, we will guide you through the process, ensuring the performance and longevity of the altered or diverted sewer is not compromised.

We are happy to meet with you at the outset of the process, prior to submission of a complete application, to ensure our requirements are clear and any issues with a site can be discussed at an early stage.

You must not commence any works on the public sewer network without written permission from Yorkshire Water.

We will determine how the diversion will be delivered, either:

  • as part of a Section 104 Agreement constructed by the developer in conjunction with adoptable sewers;
  • as a minor sewer diversion, constructed by the developer subject to an exchange of letters; or
  • as a major sewer diversion, constructed by Yorkshire Water or by the developer under our supervision and supported by a S185 legal Agreement.

Minor Alteration / Diversion to the Public Sewer Network (S185 / S106)

Minor alterations / diversion to the public sewer network under Section 185 / Section 106 of the Water Industry Act 1991 exclusively as a result of domestic development, can be applied for with Yorkshire Water.

*Please note if you choose to apply online, you will be required to pay your application fee upfront, using our secure system.*

This application is intended for use only where the works are on sewers not exceeding 225 mm in internal diameter, are less than 3 metres in depth below the existing ground level or the total length of the sewer alteration / diversion is less than 10 metres.

These works will typically include the alteration / diversion of a public sewer around property extensions, relocation of public manholes / gullies away from the footprint of property extensions and the renewal of public sewers in order to facilitate a build over in accordance with Part H4 of Building Regulations 2000.

The material of the sewer may also determine if you will be permitted to make alterations to the public sewer. If you believe that the public sewer in question is composed of either pitch fibre or asbestos cement, please contact us prior to submitting your application.

What happens next?

Once you have submitted your completed application form, proposed drawings and plans (one showing the existing situation and one showing the proposed), we will technically assess your submission.

  • we will either issue an Approval in Principle or Rejection. If you receive a Rejection, we will discuss the reasons for this with you and work with you to help identify alternative solutions
  • on receipt of the ‘Approval in Principle’, it is your responsibility to then arrange for a site inspection of the proposed works to be carried out, prior to any backfilling taking place
  • once our inspector is happy with the works undertaken, we will issue a signed S185 / S106 legal Agreement.
  • we will keep a copy for our records and return the original signed document and agreed plans back to the applicant. This is a very important document that you will need to retain and keep with the deeds of your property for when you come to sell your house.

If this application fits your needs, please contact our team to discuss your requirements further, by calling 0345 120 84 82, or emailing technical.sewerage@yorkshirewater.co.uk

Throughout the end to end application process, we will work with you to ensure your development can proceed whilst ensuring that your property, and the integrity of our sewers and network, are protected.

Minor Diversion to the Public Sewer Network (S185)

Minor Sewer Diversion Form and Guidance:

Fill in your form online Download our form

Section 185 places a duty on Yorkshire Water to divert apparatus in land, upon receipt of notice from persons who have an interest in the land, as necessary to enable that person to carry out a proposed improvement of the land. This duty does not arise when apparatus is located in, under or over any street.

Diversion of public sewers under Section 185 of the Water Industry Act 1991 can be a protracted process. All parties involved (developers, consultants, contractors, project managers) need to be aware of the process, costs, legal and technical requirements and programme implications. Developers need to ensure that sufficient time has been included in their build programme for diversion of sewers before works associated with the development commences.

Legal and financial arrangements differ depending on who carries out the works.

The developer may be permitted to carry out the work when:

  • the sewer is non-critical infrastructure; and
  • the diversion is solely in land owned by the developer.

In relation to turning flows at either end of the diversion, you must apply for a Section 106 connection application before doing so. In addition, any Section 185 legal Agreement must be signed before turning flows. Once the existing sewer flows have been diverted into the new pipework, the redundant sewer must then be abandoned in accordance with the developer’s Method Statement.

What happens next?

Once you have submitted your completed application form, proposed drawings and camera survey, we will technically assess your submission and provide an initial response detailing whether the proposals are acceptable or not.

  • if the application does not meet the criteria, we will tell you the reasons for this and what you need to do to rectify the proposals
  • once we are in receipt of all the necessary information, we will complete a full assessment in accordance with Sewers for Adoption (6th or 7th Edition) of your submission
  • we may request changes and / or further information following your initial application
  • when we are happy with the changes requested, we will be in a position to prepare the legal Agreement and invoice you for fees and 100% bond. These are clearly detailed in our Sewerage Technical Fees document for 2018-2019

Any alterations to the public sewer network shall not be commenced until the S185 legal Agreement with Yorkshire Water is in place.

During construction, our inspectors will attend site to monitor work being undertaken on site in relation to the diversion of our assets.

When the diversion is complete, it is your responsibility to provide us with ‘as built’ drawings for the works undertaken. A copy of all the drawings included within the signed S185 Agreement must be provided in ‘as built’ format.

When the flows have been turned, you can request a pre-maintenance inspection by contacting the Developer Services Customer Centre. If the diversion is found to be satisfactory, then the maintenance period (of typically 12 months) can commence.

On completion of a satisfactory maintenance inspection, we will refund 90% of the Bond, retaining 10% or a minimum of £5,000.

Just before the end of the maintenance period, it is your responsibility to contact us to arrange a Final Inspection of the diversion. Once any outstanding remedial works are completed, we will arrange for the remaining bond monies to be released.

In all cases, the sewer to be abandoned must be clearly indicated on the drawings submitted for Technical Approval and the method of abandoning the sewer (i.e. removed, grouted, fly ashed etc) must be stated.

Major Diversion to the Public Sewer Network (S185)

Yorkshire Water will undertake a feasibility study, design, supervision and construction of the diversion when:

  • the diversion is to pass through third party land;
  • the sewer is critical infrastructure of strategic importance.

Where Yorkshire Water carries out any work under Section 185 as a result of notice being served, Yorkshire Water is entitled to recover any costs reasonably incurred from the person who served the notice.

If this application fits your needs, please contact our team to discuss your requirements further, by

calling 0345 120 84 82, or emailing technical.sewerage@yorkshirewater.co.uk