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Wastewater Services

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Guernsey Water has a responsibility to remove wastewater from all properties on the island and treat it appropriately for return into the natural environment. We are also responsible for the surface water infrastructure on the island, which transports run-off from streams, properties and roads safely out to sea.


Beneath the island’s roads is a network of foul water sewer pipes totalling approximately 150km that collect sewage from around 80% of domestic households. These sewer pipes, collectively referred to as the sewerage system, are cleaned, maintained and inspected on a regular basis so as to ensure satisfactory performance throughout the life of the asset.

Most modern properties (built after 1970) have separate foul-water and surface-water pipes. Properties built prior to this, or in areas where there is not a dual pipe system, have what is termed ‘combined drainage'. This means that rainfall significantly increases flows into the foul water system. Guernsey Water operates an ongoing programme to separate surface and foul water pipes in order to reduce the risk of flooding and to make treatment of the foul water flow easier once it is transported to our Belle Greve Wastewater Treatment Centre.

There are in the region of 4,000 properties that are not presently connected directly onto the public sewer network and these have storage tanks, known as cesspits, which have a  legal obligation to be watertight and which are emptied regularly by road tankers. The sewage is taken by road to locally convenient points on the sewerage system where it is discharged.

Previous business plans have prioritised sewer network extensions to provide connections to those properties not currently served by our ‘main drain’ ; however the costs of this are high when compared with the limited environmental and public health benefits. Therefore a detailed review of this strategy was undertaken and a report submitted to the
States assembly. As a result, our previous target of a 95% customer connection rate has been rescinded in favour of including this activity in our investment plans as other priorities allow. This means that we have not planned to carry out any further sewer extensions before 2022, which will allow us to focus our resources on tackling the higher priorities of flooding and pollution from sewer overflows.

There are 57 pumping stations which transport the wastewater to the Belle Greve Wastewater Treatment Centre, where non-biodegradable matter up to 6mm in diameter is removed from the flow by mechanical screens. Grit, which would otherwise damage pipelines and pumps, is also removed. The resulting wastewater is then discharged through a long sea outfall pipe which extends more than 2km out into the fast flowing waters of the Little Russel.

Ultra-Violet (UV) rays of the sun and the natural wave action together with massive dilution provide the current bacteriological breakdown, such that any effects from the outfall are virtually eliminated once more than 20 to 30 metres away. This was backed up by scientific evidence provided by global water quality experts Intertek Metoc, who carried out an in-depth study of our bathing waters back in 2011. 

The surface water drainage system is a combination of douits, ditches, channels, culverts, pipes and 9 pumping stations that take rainwater and any other liquid run-off from the land (a surface water outfall is shown in the image below). Many landowners throughout the Island share the responsibility for ensuring that these are kept clear from debris that would otherwise block the flow of water and cause flooding.

In times of exceptionally heavy rainfall and when the main sewerage system cannot cope with the flows from combined systems (as mentioned above) then ‘stormwater’ (a mixture of rainwater and diluted sewage) overflows into the surface water drainage system. Such occurrences are carefully monitored as the frequency of these ‘spills’ is an indication as to the state and adequacy of the foul water network. The creation of additional storm storage capability at the new Belle Greve Wastewater Treatment Centre has reduced these instances significantly.

Sewage Collection

If you have a cesspit on your property, you will need to arrange for your sewage to be removed from your property by the sewage tanker fleet.

There are two options available for the collection of your sewage. You can either:

  • arrange ad-hoc sewage collections by telephoning in advance, or
  • set up a permanent regular booking e.g. 1 load every 2 weeks (depending on your individual circumstances)

Please call 247163 for advice and to make the necessary arrangements. If your property is vacated or becomes connected to the public sewer you are responsible for the cancellation of any regular order in writing.


The subsidised sewage collection charge for 2017 is £6.73 per load. All charges are reviewed on an annual basis.


In an out-of-hours emergency, an additional charge will be levied. If a cesspit urgently needs emptying or it is overflowing outside of office hours, please contact the Fire and Rescue Service on 724491.

Payment of Accounts

Customers are billed on a quarterly basis and payment can be made as follows:

  • Direct Debit - please telephone 201018 to set up this convenient facility
  • Card payments - in person at Sir Charles Frossard House or by telephoning 01616 279977
  • Cheque - can be sent by post or paid in person. Make payable to 'States Sewage Department'
  • By post: payment of accounts must be sent to The Cashier's Desk, Sir Charles Frossard House, La Charroterie, St Peter Port, GY1 1FH
  • In person: at Sir Charles Frossard House (same address as above), or at the following Post Offices - Cobo, Smith Street or Envoy House


  • Manager, Sewage Collection Service, Griffith's Yard, Northside, Vale, GY3 5TX. Telephone - 247163
  • Sewage collection orders (random collections) - telephone 245938
  • Sewage collection account enquiries - telephone 201018

Your Responsibilities

If you have a cesspit on your property, you are responsible for having it emptied at appropriate intervals to ensure that it does not overflow. Sewage that overflows from a cesspit is not only unpleasant, but it can also have an environmental impact if it enters streams.

Guernsey Water works with Environmental Health to ensure that overflowing cesspits are quickly identified and remedied. If a person is found to knowingly let a cesspit overflow, legal action could be brought against them. If you believe that a cesspit is overflowing on the Island, or you believe that sewage has entered a stream, please contact Guernsey Water on telephone number 239500 as soon as possible.

If you notice that your cesspit needs regular emptying in wet, wintry weather, but less in the dry, summery conditions, then the structural integrity of your pit may be compromised, and there may be water ingress issues. If this is the case, then you may need to get your cesspit checked by an expert.


From Twitter

We are pleased to advise that all works in La Grande Rue, Vale have been completed.
Gsy Water are carrying out urgent repairs in La Grande Rue, Vale affecting approx 40 properties. Pls call us on 239500 for more info.
Grand Bouet will be closed to traffic between 10pm & 6am on the 23rd & 24th Aug whilst investigations are carried out in the sewer network
States of Guernsey Trading Asset