Dwr Cymru Welsh Water

Private sewers: what's the problem?

Thousands of kilometres of sewers and lateral drains existed across England and Wales which, until recently, have been the responsibility of the property owners who used them. In some cases the condition of these private drainage systems was poor, leading to blockages and pipe collapses. This was a national issue, which gave rise to many problems.

The cost of repairing these private sewers and lateral drains previously fell to the owners of those sewers – often individual householders or groups of neighbours. This caused hardship for some customers and resulted in disputes between neighbours, with local authorities, insurers and with the local water and sewerage company.

After extensive consultation (including customer research) the Welsh Government decided that the private sewers would be better looked after if they formed part of the public sewer network, being owned and maintained in Wales, and adjoining parts of England, by Welsh Water. This is a huge undertaking for us and one that will be regulated and managed very carefully.

What does the transfer mean for Welsh Water?

The transfer is believed to have almost doubled the length of sewer network that Welsh Water are responsible for. This will mean a dramatic increase in the amount of work we have to undertake. Overall these transferred sewers and lateral drains are thought to be in a worse condition than these public sewers, which we were responsible for prior to 1 October 2011.

The transfer has required extensive new procurement and funding arrangements. It has been an enormous undertaking and we have been talking to the Welsh Government, Ofwat and others to ensure that appropriate measures are in place.

What exactly has been transferred to the water companies on 1 October 2011?

Private sewers and lateral drains, which connected to the mains drainage system on or before 1 July 2011, have transferred and now form part of the public sewer network.

A private sewer is a pipe that carries rainwater and/or wastewater away from more than one property to the public sewer

A lateral drain is a pipe that carries wastewater away from a single property and lies outside of the property boundary. Many thousands of lateral drains run underneath roads or even railways so can be problematic to fix

Private sewage pumping stations that serve more than one property and pump to the public sewerage system, will transfer to Welsh Water on or before 1 October 2016

Are there any sewers that have not transferred?

Yes. There are some exceptions that have not transferred or will transfer in a later time frame. These include:

  • Private drains within the property boundary
  • Surface water sewers that drain direct to watercourses
  • Land drainage and highway drainage
  • Privately owned sewage treatment works and pipes connected to them
  • Privately owned septic tanks and cesspits
  • Large ‘multi-occupier’ commercial sites
  • Private sewers and/or lateral drains where the owner has successfully appealed against the transfer
  • Private sewers built between 1 July 2011 and 1 October 2012 (but these will transfer automatically on 1 April 2013)
  • Private sewage pumping stations (but these will transfer gradually up to 1 October 2016).

Why have the pipes transferred?

Up to 1 October 2011 many householders had responsibility for pipes that were outside of their property boundary but they were often unaware of this until problems occurred. It was very difficult and expensive to sort out these problems, particularly if the liability was shared amongst several households. The aim of the transfer is to simplify things and make it easier on householders by reducing their liability and making the water and sewerage companies responsible instead.

Will my water bill go up because of this?

Yes. But the cost will be spread among all our customers and all customers will be notified of any changes to their bills. The government and the economic regulator, Ofwat, have approved this approach.

Is this extra cost fair?

Currently all water customers are paying towards upkeep of the public sewers but some also had private sewers to maintain at their own expense. In the future, the cost of sewer maintenance will be spread more fairly and customers will have the peace of mind that their sewer and lateral drain is the responsibility of Welsh Water.

Will I see a reduction in my buildings insurance premium?

Private sewers and lateral drains are often covered by domestic buildings insurance. With responsibility for these sewers and lateral drains transferring from householders, we would expect buildings insurers to review the premiums they charge homeowners. However, this will be a decision for insurance companies to make.

Can I appeal to retain ownership of my sewers?

If your sewers and lateral drains were constructed before 1 July 2011, an appeal had to be made to Ofwat before 1 October 2011 if you wanted to retain ownership of them.

Where your sewers and lateral drains were constructed between 1 July 2011 and 1 October 2012 and connect to the public sewer network you may appeal to Ofwat, before 1 April 2013, if you want to retain ownership of them. Further details can be found in our leaflet ‘Possible changes to the ownership of your drains and sewers’.

Are there any other sources of information?

There are several other publicly available sources of information. The following provides links to various bodies within the water industry:

  • Ofwat
  • Water UK
  • DEFRA
  • CC Water

How will I know if my lateral drain or sewer has transferred?

Often private sewers and drains were not mapped so we have very few records of these drainage systems to tell us which drains we are responsible for around your property.

We informed customers about the change through the national and local press, by sending all our customers literature about the changes, via our website and through liaison with the Welsh Government, Local Authorities, Housing Associations and other agencies.

From 1 October 2011 you will only be responsible for the drains on your property serving you, all other drains and sewers have transferred to Welsh Water.

I don't know where my drains run to. Do I need to find out?

No. Ownership of the private sewers and lateral drains transferred overnight on 1 October 2011 and you didn’t need to do anything to make this happen.

You are still responsible for the drains on your property and only serving you. If the problem is on these drains you will need to make your own arrangements either through your insurance company or your local drainage contractor. These contractors will also be able to advise you on the route of your drainage system. Alternatively, your property deeds or even your neighbours may be able to provide some information about the drainage arrangements for your home.

I wish to understand the layout of pipework on my property. Can Welsh Water provide me with plans or maps?

Welsh Water were not responsible for the private sewers and drains prior to 1 October 2011 and do not therefore have maps or plans of all these sewers. We have gathered very useful information from Local Authorities, Housing Associations, developers and customers and we are actively loading this into our information systems.

We will not be able to survey and map all the sewers and drains that have transferred, nor will we be able to carry out surveys for specific ownership enquires. However, we will respond to customer problems and at the same time we will take the opportunity to re-actively map those drains and sewers.

If there are specific inquiries where you need to locate the sewer to make a connection to the public sewer or build on your property then we do provide a service where we will trace the sewers in the immediate area.

Have the drains which run under my property transferred?

Any drain which is on your property and serves only your property remains private. If the drain or sewer also serves a neighbouring property then it is likely to have transferred on 1 October 2011, even if it runs underneath the property.

Who owns the inspections chambers on my property

The ownership of inspection chambers that give access to drains on your property and which only serve the drains from your property remain your responsibility. Inspection chambers and any manholes that exist on transferred sewers will be the responsibility of Welsh Water.

What happens to private drain ownership if a property boundary moves, for example if a homeowner sells land to a neighbour?

The status of any sewer/drain will be defined by whatever boundaries existed on 1 July 2011. Subsequent boundary and ownership changes will not affect the status of any drains and sewers.

I am a tenant in my property or I live in a council / housing association property. What does the transfer mean for me?

The owner of the property is responsible for the drains within the property boundary. Any sewers or drains outside the property boundary will be the responsibility of Welsh Water. If you are a tenant in a private property you should contact the owner to respond to any blockage or repair within the property boundary. If you are a council tenant or a housing association tenant then you should follow the same process that you used before the transfer. We are in contact with Local Authorities and many Housing Associations.

Our drains discharge to a private pumping station on the site. Have these drains transferred?

The private sewers and lateral drains discharging to private pumping stations, which were installed and connected to public sewers before 1 July 2011, transferred to Welsh Water on 1 October 2011. Welsh Water are planning to transfer all private sewage pumping stations and pumping mains, which form part of a sewer of lateral drain by 1 October 2016. The owners of these pumping stations remain responsible for maintenance of that pumping station until it is transferred. This allows time for us to survey the pumping stations and understand what is required to enable them to be transferred to us.

Pumping stations serving a single property and situated within the property boundary, will not transfer.

My property drains to a cess pit/septic tank or private treatment plant. Have these drains transferred?

No. These drains do not connect to a public sewer and therefore are not subject to the transfer.

I have a blockage in my sewer. I have read that you are now responsible. Please can you come and fix it?

Our regulatory responsibility is to clear blockages in public sewers and transferred assets. We do not actively pursue work relating to private drains.

If you have any problems with existing public sewers or with transferred sewers please contact our 24 hour wastewater operations line for assistance on 0800 085 3968.

You will still be responsible for the drains on your property which only serve you. If the problem is on these drains you will need to make your own arrangements, either through your insurance company or your local drainage contractor.

If you are unable to clear a blockage does this mean you will want to dig up my garden to replace the sewer?

We would only look to carry out repairs where they are necessary to help minimise the chance of problems occurring on the sewer and causing inconvenience or disturbance, such as flooding, to our customers. If any work is required on a customer's property, we will always aim to inform them of this and discuss how this will affect them, including reinstatement after the work.

I have ongoing problems with a transferred drain or sewer. When will you fix it?

Given the scale of the transfer, it will take time for Welsh Water to fully understand the extent of the transferred assets, their condition, to prioritise which ones to fix first and for us to develop a longer term improvement plan.

It will not be possible to fix all the problems overnight. Our main priority will be to clear any sewer blockages to ensure that the flows in the network are maintained. We will also carry out any urgent repairs to ensure that the service is maintained.

As we become aware of the larger problems we will investigate the cause, develop the solutions and prioritise the work to ensure that we are tackling the worst problems first. It may take some time to gather all this information and we will ensure that any affected customers are kept fully informed.

How will Welsh Water deal with problems where it is difficult to determine responsibility?

When we come across situations where it is unclear if the problem is in the public or private system we will err on the side of safety and assume it is our responsibility because we have a regulatory obligation to clear blockages in Welsh Water's assets and must do nothing to compromise this. If we find that the blockage is on the private drain, which remains your responsibility, you have the choice to contact your insurance company, contact a local drainage contractor or we will offer to clear the private blockage for a charge of £87.60. We cannot guarantee that you won’t have another blockage after we have cleared the private blockage.

We will not charge if we find that we are unable to clear the blockage. We will not carry out further works on the private drain i.e. cctv, repairs, root cutting or clean up of contaminated material.

I've paid for work on my private sewers / pumping station, am I eligible for a payment?

Any work carried out on shared drains and sewers before the transfer are the customer’s responsibilities.

We will not make any back payment for repairs carried out before the transfer date of 1 October 2011 for transferred sewers.

This also applies to private pumping stations, meaning no back payments will be made ahead of their transfer to Welsh Water, on or before1 October 2016.

I am a drainage contractor - what does this mean for me?

If you formerly provided a drainage service on the private drainage system you can continue to do so, on the sections that remain private, after 1 October 2011.

You must not carry out any work on the transferred sewers or on other public sewers. Please contact us on 0800 085 3968 if there is work in progress and it is necessary to work on the public sewers or lateral drains.

We are a commercial company and have maintenance contracts in place to deal with problems on our drainage because their correct operation is vital to our production. Will Welsh Water offer the same response times as we are currently provided?

Welsh Water has designated standards of service which we aim to adhere to when responding to reports of problems with sewers. However, there may still be a need for a customer to have their own maintenance contract because Welsh Water will not be taking over responsibility for all pipework.

What is the strategy to deal with this?

The government decided that ownership of private sewers and lateral drains in England and Wales should be transferred to water and sewerage companies as the best option for their long-term maintenance. It will not be possible to fix all the problems overnight. Our main priority will be to clear any sewer blockages to ensure that the flows in the network are maintained. We will also carry out any urgent repairs to ensure that the service is maintained.

As we become aware of the larger problems we will investigate the cause, develop the solutions and prioritise the work to ensure that we are tackling the worst problems first. It may take some time to gather all this information and we will ensure that any affected customers are kept fully informed.

There are a number of private pumping stations that we will be adopting gradually over the period up to 1 October 2016. The location and condition of many of these pumping stations is currently unknown and we need customers to tell us about them. We will be developing a programme of work to find the private pumping stations, survey the sites, determine what remedial work is required and prioritise the adoption and transfer to Welsh Water. Please let us know if you are jointly responsible for one of these by completing an enquiry on our website with details of the pumping station and location.

Does Welsh Water have a programme of improvement works for the transferred network?

Discussions are ongoing with Ofwat and others on the pace of investment for the transferred network. Our strategy is to understand the transferred network over the first few years, carry out as necessary any reactive repairs and prioritise all the known problem areas into a planned programme of work.

Where there are long lengths of problem pipes how will Welsh Water deal with these?

We do not currently know all the locations of the problem pipes. Some of this information has been made available from the data collection exercise that we carried out with the Local Authorities and other bodies but it may take some time to find them all. It will certainly not be possible to fix all the problems overnight and our main priority is to clear any sewer blockages to ensure that the flows in the network are maintained. We will also carry out any urgent repairs to ensure that the service is maintained.

As we become aware of the larger problems we will investigate the cause, develop the solution and prioritise the work with other problems in our operating area to ensure that we are tackling the worst problems first. It may take some time to gather all this information and we will ensure that any affected customers are kept informed of progress.

If you have taken over the pipe running through my back garden, will this affect me if I want to extend my property in the future?

The honest answer to this is yes, it does, although we would not want to restrict our customers from improving their homes. We do need to ensure though that the sewer is appropriately protected from such works in order to prevent any damage to the pipe and also to the extended building. When you propose to carry out building works the Local Authority will inform us of your proposed work and we may impose certain conditions to ensure the sewers and your property are adequately protected.

Have any drains, installed on my property after 1 July 2011, transferred and will they need to be inspected?

If the drainage was constructed, connected to the public sewer and connected to more than one occupied property by 1 July 2011, then it transferred to Welsh Water on 1 October 2011.

If the drainage was only connected to the public sewer between 1 July 2011 and 1 October 2012 it will remain private until the Supplementary Transfer of these private sewers and lateral drains takes place on 1 April 2013.

Any sewers and lateral drains constructed in our operating area after 1 October 2012 must comply with the Welsh Ministers’ Standards and the developer must enter into a Section 104 agreement with Welsh Water to allow this drainage to be adopted on satisfactory completion. Any new drains that will only serve your property and lie within your boundary will continue to require inspection and approval by your Local Authority or an Approved Building Inspector.

Have sewers and lateral drains, which were built in un-adopted highways, been part of the transfer?

Yes, they transferred irrespective of the adopted status of the highway.

Will my road be adopted now that you have taken over the sewers?

The transfer will allow the Highway Authorities to adopt the highways when they have not been able to do this in the past. However, it must be noted that any surface water sewers which drain directly to a watercourse or private pumping mains which are situated in the highway have not transferred and will remain private. In this instance the Highway Authority may still be reluctant to adopt the highway.

If I have a Section 38 agreement in place with the Highway Authority, which party is responsible for raising manhole covers or carrying out remedial work if the sewers it relates to have transferred?

The Section 38 agreement will still exist between the Highway Authority and yourself. Under this agreement you may still be responsible for some sewers i.e. surface water sewers discharging directly to a watercourse or pumping stations. The terms of this agreement should still be adhered to by both parties.

For all transferred sewers the responsibility for remedial works or re-setting of manhole covers will now fall to Welsh Water.

I have completed remedial works on my sewers in preparation for Section 102 adoption. Will these sewers now be vested?

Any sewers and lateral drains that were connected to the public sewer on 1 July 2011 and had properties connected and occupied will have transferred to Welsh Water on 1 October 2011. Any Section 102 application will have been completely withdrawn, or these elements withdrawn from it.

If I have a Section 104 adoption agreement in place has this agreement become void?

Sewers and lateral drains which were installed and connected to the public sewer before 1 July 2011, as part of a Section 104 adoption agreement, transferred to Welsh Water on 1 October 2011.

Section 104 adoption agreements will remain in place for the following elements:

  • Surface water sewers that discharge directly to a ditch or watercourse,
  • pipes that were laid but not connected to the public sewer prior to 1 July 2011,
  • pipes that were laid, connected to the public sewer but the houses were not occupied prior to 1 July 2011
  • pumping stations and rising mains


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