IMPORTANT NEWS - With effect from the 1 April 2018 the way that Developer Services charge for their work is changing. Please click here to find out more.
Diversion of public sewers
If there is a public sewer within your proposed development site, a diversion may be required to allow your development to progress.
Developers with an interest in land that contains public water or waste water assets can arrange for the alteration or removal those assets to allow development work to progress.
The process of altering or removing public assets to facilitate development is known as a diversion.
All or part of the diversion works may be contestable in which case the developer should be given the opportunity to undertake the works or employ a suitably qualified third party contractor to undertake any contestable elements. Please see the options below for diverting a public sewer.
In cases where the water company carries out some of the diversion work, it is only entitled to recover costs reasonably incurred.
Charges
Information on our Developer Services Charging Arrangements can be found here.
Small Build Sewer Diversion
If you are a homeowner planning a small building project and your ‘build over application’ is unsuccessful, you may be eligible for our Small Build Sewer Diversion Process.
Information and advice
• Customer Guidance Notes and Charges for Small Build Minor Sewer Diversions
• Flowchart Small build sewer diversion process
• Small build standard details sheet 1
• Small build standard details sheet 2
• Small build process - guidance - additional information
• Health and safety code of practice
Sewer diversion designed and delivered by you as part of a S104 application
We will allow most sewer diversions to be designed and constructed by developers or others requesting a diversion, using their own appointed contractors and engineers, provided that we are satisfied that they are able to fulfil design, construction, safety and legal requirements.
Before we allow a developer or other party to carry out a sewer diversion on our behalf, they must submit a full design package of the diversion for appraisal and enter into a S185 Agreement with us.
The design should be in accordance with Sewers for Adoption 7 and as part of the application, you will need to provide a CCTV to prove there are no laterals affected.
A developer must receive approval from South West Water and have a legal agreement in place before diverting any existing public sewer.
It is an offence to commence work on the public sewer without such permission. Breach of this could result in legal action being taken by South West Water Ltd.
Sewer diversion design and delivered by you separate to a S104 application
We will allow most sewer diversions to be designed and constructed by developers or others requesting a diversion, using their own appointed contractors and engineers, provided that we are satisfied that they are able to fulfil design, construction, safety and legal requirements.
Before we allow a developer or other party to carry out a sewer diversion on our behalf, they must submit a full design package of the diversion for appraisal and enter into a S185 Agreement with us.
The design should be in accordance with Sewers for Adoption 7 and as part of the application, you will need to provide a CCTV to prove there are no laterals affected.
A developer must receive approval from South West Water and have a legal agreement in place before diverting any existing public sewer.
It is an offence to commence work on the public sewer without such permission. Breach of this could result in legal action being taken by South West Water Ltd.
Sewer diversion designed and constructed by South West Water
When it is not possible for a developer to design and construct the sewer diversion, there is an option to make an application to South West Water to design and construct the diversion of the public sewer under Section 185 of the WIA.
Should you wish to apply to South West Water to carry out the sewer diversion, please download and complete the application form.
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