IMPORTANT NEWS - The way that Developer Services charge for their work changed on 1 April 2018. 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.
Technical information
Code of Practice for the exercise of pipelaying powers on private land
Guidance note where businesses are affected by streetworks undertaken by South West Water
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Where can I find plans of pipework in my area?
For location of private pipework in your area contact your local District Council or check your house deeds. If you are a land or property owner you can request an asset plan by emailing Source for Searches. For solicitors/conveyancers looking for a water and drainage...
How much water does an average person use?
The national average annual usage figures have been taken from The Consumer Council for Water and are listed below: Yearly water use in Cubic Metres m3 Number of people living in your home Low use Average use High...
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Water connections
What do I need to do if I’m planning to build an extension or conservatory?
Our sewers run under ground in streets, gardens, fields and land, so if you're building an extension you will need to check if there is a sewer nearby. We can then make sure that your home and our pipes are protected during and after the build. You can find guidance on...
Does my pipework need to meet with any regulations?
Yes, pipework and plumbing must comply with the Water Supply (Water Fittings) Regulations 1999. These are designed to stop contamination of water supplies by preventing back-flow, back-siphonage and interconnections of water from other sources.
Can I arrange to lay my own water mains and make service connection?
Yes, if you are or are employing an accredited self lay organisation, you can undertake this work. You can agree with us to lay your water mains and connections, however you will need to make an application to do so. You’ll find more details within our Self lay...
How much does a new water connection cost?
We’ll provide you with a quote which will be specific to your connection requirements after we’ve completed a site survey. The quote will be made up of: Connection costs (all work, materials required for us to make connection) Traffic management (depending on the...
Sewer connections
How do I apply for a new sewer connection?
You can complete our sewer connection application form and return it to us by email, the guidance notes contain more information. You’ll need to arrange for a drain to be laid from your property to our sewer. If you need help in locating the closest public sewer, you...
Can I build over a public sewer?
Yes, if your extension or proposed building work is over or within 3 metres of a public sewer or lateral drain, you’ll need to let us know. You’ll need to check our guidance notes to ensure you meet the criteria and if so, complete the Declaration of works form online...
Why do I need permission to build over or close to a public sewer?
We need to approve your proposal of works (even if you have already had planning permission granted) as your building could cause damage or prevent access to the sewer. Some conservatories and minor works don’t always need planning and/or building regulation approval,...
What if my extension was built over a private sewer before 1 October 2011?
If the property was built before the transfer of private sewers to us on 1 October 2011, the works are legal as there would have been no need for approval before this date. There's more information here on building over a public sewer after this date.
Commercial services
What does a CON29DW drainage and water search contain?
The Conveyancing 29 Drainage and Water (Con29DW) is designed to identify any liability that you may incur as an owner and uncover problems that may impact on the property value and lead to expensive maintenance bills. The search contains: An analysis of the risk of...
What public health and environment services do you provide?
Our Laboratory analyses environmental and recreational samples to support businesses in meeting regulatory and public health requirements.
What kind of laboratory tests and services do you carry out?
Our laboratory carries out a wide range of chemical and microbiological tests. We analyse environmental and recreational samples to support business’ meet their regulatory and public health requirements. If you’d like to make an analytical enquiry you can use our online...
Can you test our trade effluent?
Yes. Our laboratory offers an independent analytical service for trade effluents. If you’d like to make an analytical enquiry you can use our online form