Building over or near a water main

Whatever work you’re planning – whether it’s a home extension or a large development – you’ll need to know if there’s a water main in the way.

Choppy waves

Before you start building, learn what water assets might be on or near your property. You can order a map of our water and sewerage network assets for the area through our SafeMove mapping service:

If there’s a water main in the way – and you’re not able to change your building plans to avoid it – you can apply to us for the main to be diverted. We’ll design and quote the cost of the works and complete the diversion for you. To apply, please complete the application below.

Getting a public water main diverted/disconnected

Before you apply

What to think about before you apply:

  • Are you planning to raise or lower the surface level during your development? (If so, we’ll need to assess the potential impact on our water network).
  • Have you dug any trial holes on site or used ground penetrating radar to locate the water main? (If so, please provide the results with your application form).
  • What was the previous use of the land you’re developing on? (Greenfield or brownfield?)
  • If the land is brownfield, have you had a contamination assessment done?
  • Is your development project notifiable to the HSE? (If so, we’ll need a copy of your F10 Notice).
  • Do you want to hire a self-lay provider (SLP) to re-lay the main along the diverted route?
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Step 1: Apply

What you need to do:

  • Apply for a water main diversion / disconnection using the link below.
  • Make sure you include all the relevant supporting documents – these are listed with the application.
  • Pay your application fee (£334.40 incl. VAT).
  • Keep in mind that if a diversion is needed, there's a design fee of £1,725.60 (incl. VAT), which we'll invoice to you once we've processed your application.

What we’ll do:

  • Get back to you within 5 days to let you know we’ve got everything, or if we’re missing any details.
  • If needed, we’ll call you to arrange a survey of your site within 7 days of our call.
  • Provide you with a design plan (if needed) and a quote for the works within 42 days of receiving your application (please be aware it could take longer if your site is complex).
Step 2: Pay your quote

What you need to do:

  • If you’re happy with your quote, send us your payment via bank card, BACS or cheque.
  • Make sure to pay your quote and book in the work (see Step 3) within the 12-month quote validity period otherwise you’ll need to request a re-quote based on next year’s charges.

What we’ll do:

  • Process your payment and send you a VAT receipt within 24 hours.
  • Send you a mains call-off request form to complete and return when you’re ready to book in the work (see Step 3).
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Step 3: Book in the work

What you need to do:

  • Complete and return the mains call-off request form using the link below to book in the work.
  • Email your completed call-off form to
  • Pay the admin fee of £271.20 (incl. VAT) for the call-off request once you've received the invoice.

What we’ll do:

We’ll pass your work order to our delivery team, Network Plus, who will:

  • Plan in the work and set a start date that’s within 90 days of your call-off (please note: this could take longer if we find we need to close the road).
  • Call you within 7 days of your call-off to confirm the start date and arrange a pre-start meeting with you.
  • Come to meet you on site before the agreed start date.

Mains call off request form

You can download and print this PDF or fill it out using Adobe Acrobat Reader.

Step 4: We divert/disconnect the main

What you need to do:

Make sure you or your chosen contact is available on site on the agreed start date.

What we’ll do:

Our delivery team, Network Plus, will come and carry out the following work on our behalf within 90 days of your call-off request:


  • Disconnect the affected water main from the existing mains network.
  • Re-lay the main along the diverted route according to the design plan.
  • Connect the main back up to the existing mains network.
  • Backfill and reinstate any excavations made during the works.

Disconnection only:

  • Disconnect the affected water main from the existing mains network and decommission it.
  • Backfill and reinstate any excavations made during the works.
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Apply for a water main diversion/disconnection

You will need

  • site location plan showing the main to be diverted
  • site layout plan
  • F10 notice, if applicable
  • pre-construction information (CDM), if applicable.

Now accepting BACS

Apply online

Our online application form is the quickest and easiest way to apply.

You can pay your application fee by bank transfer or payment card using our secure system.

Application fee: £287 + £57.40 (VAT) =£344.40

Apply online

You can also download and print this PDF or fill it out using Adobe Acrobat Reader.

Next steps

Once you’ve applied and made the payment, we’ll survey your site so we can work out the route of the diversion. We’ll then get back to you with a quote and a plan showing where the main will be diverted – this usually takes up to 42 days, but might take longer depending on the size and complexity of the diversion.