This applies where the sewer is located on land you own or have an interest in. Please note that this does not apply to sewers located within public highways or roads.

How to apply

The first step is to complete an Expression of Interest form.

Once we've reviewed your request, we'll send you an application pack with details of the information we'll need to assess your proposal.

Please complete the application form and return it to developer.services@dwrcymru.com, together with the supporting documents requested.

Once we've received all the required information, our engineers will assess your proposal and let you know whether we can support the diversion. We'll aim to provide a decision within 28 working days.

If you need help completing the Expression of Interest form or application form, please take a look at our guidance notes.

How much does it cost?

The costs will depend on who carries out the diversion work.

Option 1: You carry out the diversion

If it's safe and appropriate for you to undertake the work, you'll be responsible for constructing the diversion in line with our requirements.

In this case, the charges are similar to those for a sewer adoption agreement and include:

• Inspection and technical review fee: £2,501.43
• Legal fee: This varies depending on the legal documents required and any Land Registry registrations. For example, a diversion agreement with no associated Deed of Grant of Easement starts from £185.63.

Option 2: Welsh Water carries out the diversion

In some cases, we'll need to carry out the work on your behalf due to operational, technical or safety considerations. You can also choose for us to undertake the diversion.

In this case, the charges include:

Application fee

An upfront, non-refundable application fee of £2,500 + VAT is payable when you submit your application. Payment can be made using a valid debit or credit card.

Once the work has been completed, we'll deduct this fee from your final invoice, so you'll only need to pay the remaining balance.

Diversion works cost

The cost of the diversion will depend on the scope and complexity of the work required. All costs associated with delivering the diversion are recoverable from the applicant.

For full details of our charges, please view our Schedule of Charges.

Important information

Under the Water Industry Act 1991, we have a duty to consider all reasonable requests to divert public sewers.

However, we may be unable to approve a diversion if it would:

• Reduce the performance of the sewer.
• Prevent us from accessing or maintaining it safely.
• Make the sewer unsuitable for its intended purpose.

This helps ensure we can continue to provide reliable service.