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Chlorine, Smell, Taste
Contents
- Do you worry about the taste or smell of your drinking water?
- What is chlorine?
- What about seasonal changes?
- How can my plumbing cause problems?
- What can I do if I am sensitive to tastes or smells?
- Remember........
- More information on drinking water quality
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 waters 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, especially during hot, dry summer months, 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 waters from different areas have different tastes. Hard water from a chalky area will have a very different taste from soft water from a reservoir in the hills.In some parts of the country, water companies can supply treated water from different sources. If your 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. Your water company or a professional plumber can 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?
Your water company will 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?
Water filters
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 water filter that is kept in the fridge.
If you do 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.
Remember........
Always use freshly drawn water for drinking or cooking, taking it from a cold water tap supplied directly off the water mains. This is nearly always the cold tap in your kitchen.
When no water has been used in the house for several hours, draw off a washing up bowlfull 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.
If there is a slight smell or taste of chlorine that you do not like, place a covered jug of water in the fridge until it is cool. It will then be fine for drinking.
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.
If you would like more information about drinking water quality you can get it from:
Your water company's public record
You can see the record at one of the company's offices. Customer services 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.Our 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 your water company's offices.Our leaflets "How Good is Your Drinking Water"
This is produced each year and is a brief summary of our Annual Report.Other Leaflets
- What do we do?
- How Good is the Drinking Water ?
- Discoloured Water
- Lead in Drink Water
- Private Water Supplies
- Problems with your Drinking Water
- Water Hardness
- DWI Summary Reports on each water company
- Tap Water, where does it come from and how is it made safe to drink?
- Using Lead-free solder for drinking water fittings
Printed versions of the above leaflets are available from us free of charge
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Drinking Water Inspectorate,
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Telephone : 020 7944 5956 - Facsimile : 020 7944 5969
E-mail: dwi.enquiries@defra.gsi.gov.ukUpdated 10 July 2002
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Some people are very sensitive to smell and taste. If you are, then this leaflet 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.