PFAS in tap water in Hainaut
Tap water in Hainaut meets the legal standard for PFAS. In the past, more PFAS was found in Chièvres and in the Centre region. After extra treatment, the levels there are much lower today. Here you can read what that means and what you can do yourself.
See the figuresShop ZeroWaterHow much PFAS is in tap water in Hainaut?
We don't have figures for every municipality yet. We are requesting them from the drinking water companies. These are the figures we do know:
- The law is met. Tap water in Hainaut stays below 100 ng/l for 20 PFAS combined. Wallonia has had no exceedance since 23 January 2024.
- Chièvres: since March 2023, an activated carbon filter cleans the water from the P1 well. The four target PFAS are now below 1 ng/l. The 20 PFAS together are about 25 ng/l.
- Centre region (including Braine-le-Comte and Écaussinnes): in 2025, two supply zones were above the 4 ng/l target. After extra treatment of the Feeder du Hainaut by Vivaqua, the four PFAS have not been detected there since 15 September 2025.
Why Hainaut?
Hainaut was one of the first places in Belgium where PFAS in tap water came to light. Near the air base in Chièvres, firefighting foam with PFAS was used until 2017. PFAS reached a well of SWDE, the Walloon water company. Between 2021 and 2023, about 12,000 people in Chièvres, Ath, Beloeil and Leuze-en-Hainaut received water with more PFAS.
In the Centre region, the raw water of the Feeder du Hainaut, a large Vivaqua pipeline, contained PFAS. In both areas, residents were offered a blood test.
Good to know: in 2024, more TFA was measured in some zones around Charleroi, Thuin, Erquelinnes and Jurbise (up to 2,400 ng/l). TFA is a very small PFAS. It is not one of the 20 PFAS in the legal standard, nor one of the four in the target.
Figures in ng/l (nanograms per litre). Unless stated otherwise: the sum of PFOA, PFOS, PFNA and PFHxS. Sources: SWDE, City of Chièvres, Walloon Public Service (SPW, March 2026), L'Avenir (February 2026), RTBF (October 2024). Status: September 2026.
What is PFAS?
PFAS is a large group of man-made substances. They are found in many things you use every day.
- Non-stick pans
- Rain jackets and outdoor clothing
- Food packaging
- Cosmetics and firefighting foam
Why is it called a ‘forever chemical’?
- PFAS hardly break down in nature.
- They enter rivers and groundwater through factories and products.
- That water is also used to make drinking water.
- They stay in your body for a long time.
Why PFAS deserves attention
EFSA, the European Food Safety Authority, says: part of the European population takes in more PFAS than is good for their health. This comes mainly from food, but also from drinking water.
It builds up
Your body clears PFAS only slowly. Small amounts add up over the years.
Effect on your immune system
According to EFSA, even small amounts of PFAS can make your immune system work less well.
The target is stricter than the law
Flanders and Wallonia aim for 4 nanograms per litre for four PFAS. The law is less strict. Below you can read the difference.
Law and target: what's the difference?
There are two numbers you may read about. They don't measure the same thing, but this is how it works:
- The law (EU): a maximum of 100 nanograms per litre for 20 PFAS combined. It applies across the EU from 12 January 2026. Brussels (2024) and Wallonia (2025) already applied it earlier.
- The target: 4 nanograms per litre for four PFAS combined (PFOA, PFOS, PFNA and PFHxS). Flanders and Wallonia want to reach this by 2028. It is based on EFSA advice.
The target is stricter because it looks at the four PFAS that have been studied most and that EFSA considers most important for your health.
Good to know
- Tap water in Belgium is safe to drink, say VMM (Flanders), SWDE (Wallonia) and Vivaqua (Brussels).
- Drinking water made from groundwater usually contains less PFAS than water made from surface water such as rivers and canals.
- About 97% of the tap water in Brussels comes from Wallonia.
- Boiling does not remove PFAS from your water.
ZeroWater filters PFAS
Just keep drinking tap water. Want to take in less PFAS through your water? Then a certified filter is a simple extra step.
less PFAS in your water
This percentage applies to PFOA and PFOS, the two best-known and most studied PFAS. The ZeroWater 5-stage filter has been tested for these to the NSF/ANSI 53 standard and certified by the independent institute IAPMO. View the certificate.
Tested, certified
Not a promise, but an independently tested result. Tested with far more PFOA and PFOS than is found in Belgian tap water.
More than just PFAS
The filter is also certified for lead, chromium-6, mercury and chlorine. That makes your water taste purer too.
See it for yourself 000 PPM
Every jug comes with a TDS meter. It shows how pure your water is. Does it show 006? Then it's time for a new filter.
Start filtering right away
Choose the jug that suits your household. A filter is included, so you can filter your first jug of tap water straight away.
1.7 litresZeroWater 1.7 litre jug
Compact and light. Fits in most fridge doors. Handy for 1 or 2 people.
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4.7 litresZeroWater 4.7 litre jug
More water in one go. For families who drink a lot and want to refill less often.
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5.4 litresZeroWater 5.4 litre dispenser
With a tap. Put it in the fridge or on the counter and pour your water whenever you like.
Add to cartView product →Questions about PFAS in Hainaut
Can I still drink the tap water in Hainaut?
Yes. Tap water in Hainaut meets the legal standard. SWDE and the Walloon government say there is no reason to stop drinking tap water. Want to take in less PFOA and PFOS? Then you can filter your water as an extra step.
What happened in Chièvres?
Between 2021 and 2023, PFAS from a well near the air base ended up in the tap water of about 12,000 residents in Chièvres, Ath, Beloeil and Leuze-en-Hainaut. Since March 2023, an activated carbon filter cleans the water. The four target PFAS are now below 1 ng/l, and the water meets the legal standard.
What is TFA, and is it in my water?
TFA is the smallest PFAS. It is found in more and more water across Europe. In 2024, up to 2,400 ng/l was measured in some zones in Hainaut. TFA is not part of the legal standard of 20 PFAS. ZeroWater has no certificate for TFA, so we make no promises about it.
Does ZeroWater filter all PFAS?
The honest answer: ZeroWater is certified for PFOA and PFOS, the two best-known PFAS. There are thousands of types of PFAS. We have no certificate for the other types, so we don't make any promises about them.
Does the TDS meter show how much PFAS is in my water?
No. The meter measures dissolved solids such as limescale and metals. PFAS are present in such tiny amounts that a TDS meter can't measure them. The meter does help you see when your filter is used up: when it shows 006, replace your filter.
How do I find out about my own address?
Ask your drinking water company. In many municipalities that is SWDE, but some have their own water service. Your water bill shows which company supplies you.
Know what you drink
Just tap water, but with less PFOA and PFOS. For you and your family at home.
Shop ZeroWaterReplacement filters- SWDE – Water and PFAS: what do I need to know? swde.be
- City of Chièvres – PFAS: frequently asked questions (in French). chievres.be
- Wallonia – PFAS pollution in the province of Hainaut: state of play (in French). wallonie.be
- SPW – PFAS in Walloon distribution water, state of play, March 2026 (PDF, in French). environnement.wallonie.be
- L'Avenir – PFAS in the water of the Centre region: latest results, February 2026 (in French). lavenir.net
- RTBF – 13 Walloon supply zones with TFA above the guide value, October 2024 (in French). rtbf.be
- RTBF – Chièvres: 12,000 residents and PFAS in tap water, November 2023 (in French). rtbf.be
- EFSA – PFAS in food: EFSA assesses risks and sets tolerable intake (2020). efsa.europa.eu
- EU Drinking Water Directive 2020/2184. eur-lex.europa.eu
- ZeroWater Performance Data Sheet, IAPMO certification to NSF/ANSI 53 and 42. View PDF
ZeroWater is certified for the reduction of PFOA and PFOS. Results were achieved under laboratory conditions; actual results may vary.