Water Quality
Tap water in Guernsey is of a very high quality – this is backed up by the thousands of samples that are taken by Guernsey Water staff, the vast majority of which pass the stringent water quality guidelines set by the DWI (Drinking Water Inspectorate) in the UK.
2009 saw the highest ever recorded level of water quality in the Island, with 99.86% of samples exceeding the strict standards set by DWI. This level of water quality compares very favourably with all areas in the UK and Europe.
Click here to see the water quality results in detail for Guernsey in 2009.
Catchment Protection
The Water Catchment Area covers the majority of the island, and as its name suggests, ‘catches’ the precipitation which falls, and directs it through streams into the various storage reservoirs dotted around the island. This water is then treated and distributed to customers.
The Catchment Area is therefore a vital part of the water collection and treatment process, as it essentially forms the first stage. Guernsey Water recognises this, and employs a number of staff to ensure that the Catchment Area remains free from potential pollution and contamination by taking a proactive approach, and pre-empting possible problems through releasing educational material to the public. Examples of these documents can be viewed by clicking on the appropriate title:
Application of Herbicides within the Catchment Area
Advice for the Disposal of Oil Storage Tanks
Disposal of Water and Waste Water from Domestic Swimming Pools and Spas
If you are in any doubt about a Catchment Area issue, or you think that you have witnessed pollution or a pollution incident, then please contact us on 724552, or on our emergency number 264073 out of hours.
Testing and Sampling
Guernsey Water tests its treated water on a daily basis for bacteriological and chemical quality in line with the UK Drinking Water Regulations. These tests are undertaken at three different stages in the water treatment process:
- At Water Treatment Works (St Saviours, Kings Mills, Juas)
- At Service Reservoirs (Forest Road storage tanks and Water Tower, Frie Plaidy)
- At customer taps (throughout the island)
The tests cover a range of over 100 different parameters. In addition to this we monitor our raw water resources and Catchment Area very carefully to ensure that we can continue to supply water in line with the regulatory requirements. We also publish these results on an annual basis.
Guernsey Water also undertake testing and sampling for customer complaints and queries as necessary.
Water Hardness
Water hardness depends on which part of the island you live in, and which part of the Catchment Area you are in. Generally speaking, if you live in the south of the island (St Saviours catchment), then the water is moderately soft to slightly hard. If you live in the north of the island (Juas/Longue Hougue catchment), then the water is moderately hard. Click here to learn more about water hardness, and to see a map of the Catchment Area and how it is split according to which WTW it is served by.
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