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 pollution and contamination by taking a proactive approach and liaising with potential polluters.
Guernsey Water also pre-empts possible problems by releasing educational material to the public. Examples of these documents can be viewed by clicking on the appropriate titles below:
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, Longue Hougue and Kings Mills)
- 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 publish these results on an annual basis.
Guernsey Water also undertakes testing and sampling for customer complaints and queries as necessary.
Tastes and Odours
Customers occasionally report that their tap water has an unusual taste or odour. These complaints are often of a chlorine smell or taste, and sometimes this only occurs in boiled drinks.
Chlorine is added to the water during the final stage of the treatment process. It acts as a disinfectant and a small residual amount is usually present in the water that comes out of your tap. This is to ensure that the quality of drinking water is maintained through the pipe network.
In order to remove the taste of chlorine, fill up a jug with tap water and keep this in the fridge. Not only will the chilled water taste better, it will also lose any chlorine smell or taste.
Make sure the jug is kept covered to avoid other strong smells within the fridge tainting the water, and discard after 24 hours.
Discoloured Water
You may find that your tap water has a cloudy or white appearance. This can occur when the tap has not been used for a little while e.g. first thing in the morning or on return from holiday. The most common cause for this is tiny air bubbles in the water.
You can confirm this by pouring a glass of water and standing it for a few moments. The cloudiness should clear from the bottom of the glass upwards.
Air in water is completely harmless, and in many cases can be removed by adjusting the stop tap/stopcock.
If the cloudiness persists or clears from the top of the glass downwards, then please contact us, and we will try and rectify the problem for you.
If your water looks slightly brown, this may be due to tiny rust deposits from iron water mains. This can be caused by a main burst, works on a main, or the reinstatement of a pipe which hasn't been used for a while.
If works are being carried out on a water main near you, Guernsey Water will endeavour to contact you in advance of the works taking place. If the brown water does not clear after running your tap for a while, then please contact us. You could check whether your neighbours are also experiencing brown water - if it is just your property that is affected, then it is likely to be an issue with your property's internal plumbing.
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 (Longue Hougue catchment), then the water is moderately hard. Click here to learn more about water hardness in Guernsey, and to see a map of the Catchment Area and how it is split according to which WTW it is served by.
Water Recycling
Anybody wishing to install any plumbing system that is intended to recycle water must contact Guernsey Water before they do so.
Rainwater harvesting (the collection and re-use of rainwater) and grey water recycling (the re-use of water from laundry, bathroom use, kitchen use etc.) are currently being mentioned in the media as efficient ways of reducing waste water from a property.
However, as rainwater and grey water both contain many impurities which are potentially hazardous to our health, Guernsey Water advises people to seek their advice before proceeding with the installation of water recycling systems.
If you have any queries on this, please contact us.
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