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Do you worry about the taste or smell of your drinking?

Some people are very sensitive to smell and taste. If you are, then this information may be of use to you. It explains why you may notice smells or tastes in your drinking water and what you can do if you are particularly sensitive to them.

What if my water smells or tastes?

We would like to put your mind at ease. Drinking water in England and Wales is of a very high quality but you may sometimes notice a slight taste or smell, particularly of chlorine. If you do there is no cause to worry. But if you notice a particularly bad or strong smell or taste which means you cannot drink the water, or you notice a smell or taste for the first time, you should contact the Company immediately.

Why does water smell or taste?

Any of the following could cause people to notice a smell or a taste or a change in the smell or taste of their drinking water:

* The use of chlorine as a disinfectant
* Seasonal changes
* A change in your water supply
* Moving from one area to another
* Your plumbing

What is chlorine?

Chlorine has to be used carefully, but it is harmless when used in very small amounts as a disinfectant to treat drinking water. It is also commonly used in various brands of sterilisers for baby feeding bottles and equipment. It is also used in higher concentrations to disinfect water in swimming pools.

Why use chlorine?

It is absolutely essential that drinking water should be safe to drink and contain no harmful bacteria capable of causing diseases. Chlorine is a very effective disinfectant. It has been used for 100 years. The addition of chlorine in small amounts at water treatment works gives maximum disinfection action before water reaches your tap.

Why can I taste or smell chlorine in my water?

To be absolutely sure that disinfection is maintained throughout the water mains, small amounts of chlorine are allowed to stay in the water supplied to your tap. This may result in an occasional slight smell of chlorine when you turn your tap on or a slight taste of chlorine in the water. A good, safe way to overcome this smell or taste is to place a covered jug of water in the fridge before drinking – cool water always tastes better, but throw away any unused water after 24 hours.

Are these low amounts of residual chlorine harmful?

No. The small amounts of chlorine in your water prevent harmful bacteria growing in the water mains or your pipes. You can rest assured that the usual amount of chlorine in water leaving treatment works is safe and well within the World Health Organisation guidelines.

What about seasonal changes?

Much of our drinking water is obtained by treating water taken from rivers and reservoirs. In summer, these waters sometimes have a musty or earthy smell or taste before they are treated. Treatment removes most of these smells and tastes but at times the drinking water may have a slight musty or earthy smell or taste.

Are these smells or tastes harmful?

No. The slight smell or taste is harmless.

What if my water supply changes or if I move house?

The content of water is complex and varies from area to area, often because of the different rocks and soils through which it passes. Treated water from different areas has different tastes. Hard water from a chalky area will have a very different taste to soft water from a reservoir in the hills.

The Company can supply treated water from different sources. If the Company needs to change supplies, for example because of increased use of water in the summer, you may notice a change in the taste. Similarly, if you move to another area you may notice that the water tastes different.

How can my plumbing cause problems?

Water may dissolve small amounts of substances from your plumbing which may cause strange tastes. For example:

* Metallic or bitter tastes come from copper, iron or galvanised pipes
* Plastic tastes from plastic pipes
* Rubbery or metallic tastes from tap washers

Only materials suitable for use with drinking water should be used and the tank in your loft kept clean and covered. The Company or a professional plumber may be able to advise.

Water from water softeners should not be drunk or used to mix baby foods because it can contain too much salt. You should always have a tap with unsoftened water for drinking and cooking. Incorrectly installed water softeners can cause salty tastes and allow contaminated water to get into the drinking water pipes.

How can I find out if it is my plumbing?

The Company may be able to help you find out if there is anything wrong with your household plumbing. Alternatively, you could get advice from a professional plumber.

What can I do if I am sensitive to tastes or smells?

We do not think it is necessary to use water filters. Cooling tap water in the fridge is all that is needed. However, if you feel a filter would make your water taste better, you could always try using either a water filter that has to be plumbed in or attached to your tap or a jug type filter that is kept in the fridge.

If you decide to use a filter, you must follow all the manufacturer’s instructions carefully.

If you are using a jug type water filter, you must not let the water stand in the jug for longer than 24 hours as this could result in bacteria being produced. You should always throw away any unused water after 24 hours and refill the jug. Also the jug and filter must be kept very clean to be effective and the covered jug kept in the fridge.

A filter attached to your tap or plumbed in must be fitted properly and the filter cartridge changed regularly according to the manufacturer’s instructions, otherwise harmful bacteria could develop.


Always use freshly drawn water for drinking or cooking, taking it from a cold tap supplied directly off the water mains. This is nearly always the cold tap in the kitchen.

When no water has been used in the house for several hours, draw off a washing up bowlful before taking water for drinking. This will ensure that you do not drink water which may have been standing for a long time in your pipework. There is no need to waste the water as you can use it for other things such as watering plants.

Do not use water from a hot water system or your bathroom taps for drinking or cooking because it usually comes from a storage tank in the loft and is not as fresh or as safe as water directly from the mains.

If you notice a particularly bad or strong smell or taste which means you cannot drink the water, or you notice a smell or taste for the first time, you should contact your water company immediately.

Discoloured Water

Drinking water in England and Wales is of a very high quality but occasionally things go wrong. Sometimes this can lead to people getting drinking water which is discoloured. This information answers the questions most often asked about discoloured water.

What causes discoloured water?

There are many possible causes, but the most usual reason is the disturbance of any deposits present in the water mains. This can happen when there is a change in the direction or speed of the flow of water. Changes in flow can occur for a number of reasons, for example, a burst on a water main, the opening or closing of valves, bringing a mains back into use after repairs, a water company having to move water from one area to another to cope with changes in demand and use of water for fire fighting.

Very occasionally it may be caused by the condition of your service pipe connecting your house to the water main or the condition of the internal plumbing within your house.

These problems can turn the water orange, brown or grey. It may also be white as a result of chalk deposits or excess air. White water caused by excess air clears from the bottom up on standing freshly poured water in a glass and is not something to worry about.

Why are there deposits in the mains?

If the water is discoloured you should not assume that it is safe to drink until you have sought advice from your water company. If the discoloration is due to mains deposits, these are mostly iron and manganese and as such are not likely to be harmful to your health. However, you may not wish to drink the water or give it to your family because it looks and tastes so unpleasant.

Is anything being done about this?

The Company maintains its distribution systems to minimise the amount of deposits in the mains by carrying out flushing or other means. The Company also operates its systems to avoid the deposits being picked up by the water flow.

Water companies are dealing with iron corrosion by lining or replacing the affected mains. They are tackling the worst affected areas first. A few water companies have already completed these programmes but others will take up to the year 2010 to complete them. There are about 315,000 kilometres of water mains in England and Wales, although not all will need work on them.

What should I do if I get discoloured water?

If you and your neighbours are getting discoloured drinking water then contact your water company immediately.

If you consider the Company does not give you a satisfactory explanation or does nothing then you should contact your local Consumer Council for Water.

The Company has to notify the Drinking Water Inspectorate of any widespread incident involving discoloured water, who then investigate the cause and assess the appropriateness of the actions taken by the Company. The Company must also notify the local authority and health authority of any problems.

If it is only you and not your neighbours getting discoloured water, the problem may be with the pipework in your home. The Company may be able to give you advice or you could contact a qualified plumber, such as one registered with the Institute of Plumbing.

You should contact the Company if you think that you have suffered loss or damage as a result of being supplied with discoloured drinking water. If you are dissatisfied with the Company’s response then you should contact your local Consumer Council for Water.

Where can I get more information about drinking water quality?

If you would like more information about drinking water quality you can get it from:

* The Company’s public record

You can see the record at the Company’s office at Packsaddle. Water Quality staff will explain the result of tests and tell you what is being done to rectify any failures. You are entitled to a free copy of the record for the area in which you live. Alternatively, you can write to the Company for details.

* Your local authority

Water companies are required to give local authorities information about the quality of water supply in their areas.

* Annual Reports

These are lengthy reports containing a great deal of detailed information about the quality of drinking water in England and Wales. They can be bought from The Stationery Office. You may be able to see a copy at a main library or at the Company’s office.

Free leaflets about the following are also available from us:

- What do we do
- Lead in drinking water
- Chlorine, smell and taste
- Water hardness
- Private water supplies
- Problems with your drinking water