That swimming pool taste or smell in your tap water is chlorine, added by your water company to keep the water free of harmful bacteria all the way to your tap. At the levels used it is considered safe to drink, but many people dislike the taste, and it can affect tea, coffee, cooking and fish tanks. A carbon filter removes it simply and cheaply.
At a glance
- Why it is there: disinfection, required to keep mains water safe through the pipe network
- Who notices it: mains water users, especially close to a treatment works or after mains repairs
- Signs: swimming pool taste or smell, stronger in cold water fresh from the tap
- Fix: activated carbon filtration
Why is there chlorine in tap water?
Water companies disinfect water at the treatment works and leave a small residual of disinfectant in it, so that any bacteria picked up on the long journey through the mains are dealt with before the water reaches you. This residual is a key part of why UK mains water is so safe. Most areas use chlorine; some use chloramine, a combination of chlorine and ammonia that lasts longer in the network and has a milder smell.
You may notice the taste more if you live close to the treatment works, after work on the local mains when the dose may be increased, or when the water is cold and fresh from the tap. If the taste suddenly becomes much stronger, your water company can check it.
Is chlorine in tap water safe?
The levels used in drinking water are very low and are considered safe to drink by UK regulators. The issues are mostly about taste and smell, plus a few specific uses:
- Tea, coffee and cooking. Chlorine dulls flavour, which is why cafés filter their water. See our food service water filters.
- Fish ponds and aquariums. Chlorine and especially chloramine are toxic to fish, so water must be dechlorinated before it goes in.
- Disinfection by-products. Chlorine can react with natural organic matter to form compounds such as trihalomethanes, which water companies must keep under a legal limit of 100 µg/l total.
Chlorine and private supplies
Private supplies normally have no chlorine added, which is why they rely on UV disinfection to deal with bacteria. UV works at the point of treatment but leaves no residual, so storage tanks after the UV unit need to be kept clean. See bacteria in water.
How to remove chlorine from water
- Activated carbon removes chlorine very effectively, along with many taste and odour compounds. Choose a carbon block filter for drinking water or granular activated carbon for higher flow.
- Under-sink drinking water filters with a dedicated tap give chlorine-free water for drinking and cooking. Browse drinking water filters.
- Whole house carbon systems remove chlorine from every tap and shower. See whole house water filtration.
- Chloramine areas need carbon with longer contact time or catalytic carbon, as chloramine is harder to remove than chlorine.
- Reverse osmosis systems include carbon stages and remove chlorine along with dissolved contaminants. See reverse osmosis.
Leaving a jug of water in the fridge lets some chlorine escape, but this does not work for chloramine.
Related contaminants
Why Wrekin Water
Wrekin Water is a family run company based in Bettisfield, Shropshire, serving more than 50,000 customers over 15 years and rated Excellent on Trustpilot. We stock carbon filters and replacement cartridges from major brands and our own range. Ask our team which filter suits your water.