Does the shower in your holiday home in France smell like a swimming pool, but not at home in the Netherlands? That is right. In many countries chlorine is added to tap water; in the Netherlands it normally is not. Besjaar looked into how that works, when chlorine is used after all and what it means for your shower.
The short answer
No. Dutch drinking water is produced without chlorine. Groundwater has never been chlorinated here, and in 2005 the last chlorine disinfection was replaced by UV light. Only in exceptional situations, such as after contamination of the mains, does a water company temporarily use a small amount of chlorine.
Why the Netherlands stopped using chlorine
Until the 1970s, surface water around Rotterdam and Amsterdam was still disinfected with chlorine. Then Rotterdam chemist Joop Rook discovered that chlorine reacts with natural substances in water to form by-products such as trihalomethanes. That made Dutch water companies rethink their approach. They chose a method in which the water enters the mains so clean that chlorine is not needed.
So how does Dutch water stay safe?
Dutch water companies use several barriers in a row:
- Soil passage. Water seeps down through dunes or riverbanks. On the way, the soil filters out most pathogens.
- Treatment. Sand filters, activated carbon and, where needed, ozone or membranes remove the rest.
- UV light. UV installations make bacteria and viruses harmless without adding anything to the water.
- Stable water and good pipes. The water contains so few nutrients that bacteria can hardly grow in the pipes.
- Strict monitoring. Water companies take samples all year round, from the source to the mains.
At a few locations, water companies use chlorine dioxide as an extra step. Nothing of it can be measured at the tap.
When do water companies use chlorine after all?
Only when necessary, and temporarily. For example after work on the pipes, or when bacteria have been found in the mains. In November 2017, for instance, Evides flushed the water mains in Vlaardingen with a small dose of chlorine after E. coli had been found. Residents were advised to boil their water, and the water could temporarily smell and taste different.
Suddenly smell chlorine at home in the Netherlands? Check your water company's website for works or notices. Your water bill shows which company supplies your water. If the smell persists, contact them.
And abroad?
There, chlorine in tap water is often perfectly normal:
| Country | Chlorine in tap water? |
|---|---|
| Belgium (Flanders) | Yes. Farys adds chlorine to prevent bacteria during transport, about 0.25 milligrams per litre. |
| France | Usually. Chlorine disinfects the water and stays active in the pipes. At a high threat level, a minimum amount of chlorine is mandatory. |
| Germany | Usually not. Chlorine is only added in certain situations, for example after heavy rain. |
| Spain | Usually. Water companies routinely measure residual chlorine in tap water. The Murcia region carried out more than 47,000 of those measurements in 2024. |
That chlorine is added deliberately and is safe in the amounts used. It does explain the swimming-pool smell in the shower on holiday.
What does this mean for a shower filter?
In the Netherlands, chlorine is not a good reason to buy a shower filter. There is normally nothing to filter out. We would rather say that honestly.
Do you live in Belgium, France or Spain, or do you take your shower head to a holiday home? Then it is a different story. Filter layers such as calcium sulfite and KDF break down free chlorine, even in warm water. Ordinary activated carbon does this less well in hot water. How the filter types differ is explained in how does a shower filter work?
The Besjaar Shower Head with Filter contains calcium sulfite, among other things. You will find all options in the Besjaar shower filters. In the Netherlands, showering is mostly about limescale. For that, read water hardness by province and water softener or shower filter?
Frequently asked questions
Is there chlorine in Dutch tap water?
Normally not. Dutch drinking water is produced without chlorine. Only after an incident or work on the pipes does a water company sometimes temporarily use a small amount.
Is tap water without chlorine safe?
Yes. Dutch water companies treat water with soil passage, filters and UV light, and monitor it strictly. That is why chlorine is normally not needed.
Why does my tap water smell of chlorine?
Your water company may be temporarily flushing the pipes with chlorine, for example after works. Check your water company's website. If the smell persists, contact them.
Besjaar makes shower heads and filters for Dutch bathrooms, from Assen. Better water, every day.
Sources
- Smeets et al. (2009) – The Dutch secret: how to provide safe drinking water without chlorine in the Netherlands
- Radar – Evides gaat waterleidingnet Vlaardingen doorspoelen met chloor (2017, Dutch)
- Farys – Kraantjeswater (Dutch)
- Anses – Chlore dans l'eau du robinet (French)
- Utopia – Chlor im Trinkwasser (German)
- Región de Murcia – Indicadores de calidad del agua de consumo 2024 (Spanish, pdf)