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Maintaining cesspools, septic tanks and sewage treatment plants

This advice applies to Wales

If your property isn’t connected to a public sewer, you may have a cesspool, septic tank or a sewage treatment plant. If you have one of these, you don’t have to pay sewerage charges to your water or sewerage company. However, you are responsible for making sure your sewerage system is properly maintained.

If you don’t maintain it properly, your local authority has the power to force you to do so. You may be able to connect to a public sewer, or ask for one to be provided.

In Wales, septic tanks and small sewage treatment plants must be registered with the Environment Agency. From 1 April 2013, the Environment Agency in Wales has become part of Natural Resources Wales.

Read this page to find out more.

What is a cesspool?

A cesspool, also known as a cesspit, is a large tank which stores sewage from your property. Cesspools need to be emptied frequently. This can be done either by the local authority or a private contractor. The charge is often at cost price, which may still be expensive.

What is a septic tank?

A septic tank treats raw sewage and needs to be inspected and emptied regularly. The local authority will usually do this for a charge, although in some areas you’ll need to contact a private contractor.

What is a sewage treatment plant?

Some properties have their own small sewage treatment plants. These treat raw sewage in a tank which needs to be maintained and emptied.

Registering your septic tank or sewage treatment plant

If your home has a septic tank or a small sewage treatment plant, you have to register this with the Environment Agency (or from 1 April 2013, with Natural Resources Wales). You should have done this by 1 January 2012. There are some exceptions for households which have an environmental permit.

You don’t need to register acesspool or cesspit as these are sealed systems with no discharge into the environment.

In most cases, registration is free. You can get information about how to register on the Natural Resources Wales website.

If a property is rented, the tenant, rather than the landlord, is responsible for registration.

Businesses and other organisations can find out from Natural Resources Wales whether theyshould be registered.

Do you have to pay sewerage charges?

If you have a cesspool, septic tank or sewage treatment plant, you usually don’t have to pay sewerage charges to your local water or sewerage company. However, there are some circumstances when you may have to pay these charges. This is when:

  • your tank is connected to the public sewer for any reason, for example, to allow for overflow
  • your surface water drains are connected to a public sewer even if your cesspool or septic tank is not. In this case, you should pay a partial sewerage charge.

Can the local authority insist you carry out repairs to your cesspool or septic tank?

Your local authority has a duty to make sure that cesspools and septic tanks are kept in good repair and are emptied or cleaned when needed.  In certain circumstances, the local authority can insist you carry out repairs or do the work themselves and charge you for it. They can do this if the cesspool or tank is causing a risk to public health or is a nuisance for example, if it’s leaking or overflowing.

If you want to connect to a public sewer

All water and sewerage companies have a duty to provide public sewers to make sure the area is effectively drained. Usually, you have the right to connect the drain from your property to the public sewer – although you may have to pay for this.

What if there isn’t a public sewer?

If there isn’t a public sewer, you can ask your local sewerage or water company to provide one. The company should agree to this if your current drainage system is inadequate or causing environmental or public health problems.

If the sewerage or water company refuses to provide a public sewer or you are unhappy about their timescale for the work, you can appeal to Natural Resources Wales.

You may be able to get a grant or loan from your local authority to cover the cost of installing a new septic tank where no main drainage is available.

Can the local authority insist you connect to the public sewer?

If the nearest public sewer is more than a hundred feet from your property and your drain runs into an adequate cesspool or septic tank, your local authority can’t insist that you connect to the public sewer.

However, they can insist if they agree to pay for the additional costs of connection, including construction, maintenance and repairs.

Next steps

Other useful information

  • You can find more information about water regulations on the Natural Resources Wales website at www.naturalresources
  • To find out which water or sewerage company supplies your  area, go to  the Consumer Council for Water's website at:
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