Working Near Our Pipes

We’re committed to maintaining and operating our network of water and wastewater pipes in a safe and reliable way, with minimum inconvenience to our customers.

Working near our pipes

This video explains what to consider before you start any building work on your new project. This is to make sure that water and wastewater supplies are not impacted by any work on or around our pipes.

To ensure our water continues to flow and meet the required high standards and that the wastewater is taken away and treated ready to return to the environment, we have to coordinate lots of people from across our organisation.

So, if you're planning works over or near to one of our mains or sewers anywhere in the North West of England, you will need to contact us before you start any works.

Please call 0345 026 8989 option 1 or email

It is important that you minimise the risk of damage to our network, so we will need to check that your development doesn’t reduce capacity, limit our access to repair or maintain or inhibit any other services that we provide.

If you suspect you have, damaged one of our pipes, please contact us urgently on 0345 672 3723 (24-hours-a-day).

  • How to locate our water and wastewater pipes

    For companies that need to dig in the public highway there are maps available which show the location of clean water pipes and sewers. This information is restricted and you will need to apply to get access, please go to Maps for Safe Dig.

    If you're a member of the public or a developer and you’d like information on drainage and water mains near or on your development, you can buy local maps. These are offered by a number of companies including United Utilities. If you would like to buy a plan from us please see our Property Searches service.

  • Once you’ve searched our maps and examined where our pipes are within your development, you should see how close your work will be to our mains or sewers.

    Contact us for early conversations

    Before doing any work, contact us to discuss how your development could affect our pipes and how we can support you. Early conversations can help prevent any delays on site and help make sure your work goes smoothly.

    For us to assess your development and the impact on our pipes we will need between 4-6 weeks notice depending on the complexity. If it's more complex we may need longer.

    You can email us at DeveloperServicesWater

  • Trial holes

    Before doing any work, you should have contacted us to discuss how your development could affect our pipes and how we can support you. 

    To confirm the location of the pipe, trial holes will be required to determine the route/depth of the asset before any on site work can begin.

    Trial holes can be carried out by competent individuals but prior consent must be sort from UU

    Who will carry out the trial holes?

    If you would like to undertake trial holes or request that UU carry out these works please contact Developerserviceswater

    If you are planning on carrying out the trial holes yourself, you will need to provide a site plan and a Risk Assessment and Method Statement (RAMs). We will then review these and assess whether you can proceed. 

    UU carry out trial holes

    If you would like UU to carry out the trial holes, you will need to provide a site plan and land owner details. We will then send you a quote for you to review and accept.

    Next steps

    It may be possible for the assets to remain in situ depending on your proposals. We can discuss this further with you and explain the protection measures you will need to adhere to. United Utilities preferred solution is to work with you so your development can continue with the least disruption to our network. So communicating with us early is vital.

    We’re unlikely to permit any development or structure within ten metres of our largest water pipes, known as trunk mains, or within six metres of our distribution mains. If you intend to do this, you’ll need to apply for a diversion.

    If you’re planning work near our sewers you may need to divert, build over or close a sewer.

Further information

Please read the information below if you are carrying out CCTV work on sewers and/or manholes, or planning any works next to our pipe lines.

  • If you need to carry out any investigation or CCTV survey work on the public sewer system please fully complete the Request for permission to work on a public sewer (CCTV investigation) form and return to and the relevant Network Drainage Engineer for your area will assess the request and issue an approval, if appropriate.

    Contractor requirements for carrying out CCTV investigation

    All of United Utilities’ sewers come under the ‘Dangerous Substances and Explosive Atmospheres Regulations’ (DSEAR) and are classed as zone 1. As a result, all CCTV survey equipment that is used within the sewers needs to be intrinsically safe (Ex rated), so it does not ignite in a potentially explosive atmosphere.

    • All United Utilities’ sewers are classified as confined spaces from the point of entry, so personnel working in the public sewer network must hold current confined space training certificates.
    • All work within any United Utilities’ sewer network is to be carried out between 08:00 – 16:00 hours on normal working days.

    Operational issues

    In the event that the camera unit becomes stuck, snagged or irretrievable, do not enter the public sewer network, you must call 0345 672 3723 to report the problem. We will arrange for a United Utilities operative to attend site to assess the situation.

Standard conditions for works 

Standard conditions for work carried out over, under or adjacent to a UU Pipeline which can include multiple UU Pipelines laid adjacent to each other. See the guidance document below for further guidance.

Standard conditions for works adjacent to pipelines

The Mersey Valley Sludge Pipeline

The Mersey Valley Sludge Pipeline is a 400mm ductile iron pipeline which runs from Oldham WwTW in Manchester to Liverpool WwTW in Regent Road Liverpool. The pipeline is owned by United Utilities and laid and operated under the 1977 North West Water Authority Act. It operates at pressures up to 25 bars (375 psi) and a flow rate of up to 205 ltrs/sec. Its location is indicated by marker posts at regular intervals, including at every gas release valve and sludge washout valve location.

MVSP UU pipeline contractor work guidance