PFAS in Gauchy's tap water: 9 ng/L, 18x our 0.5 ng/L benchmark
Last PFAS check: · Source: Hub'eau
PFAS in drinking water
18× above our health benchmark
0.5 ng/L is our benchmark, not an official limit. Same EFSA method as Sweden, Denmark and the Netherlands, but stricter. It's a yearly average, compared here with the latest check.
Sample taken in Fonsomme, on the same distribution network as Gauchy (UDI SAINT QUENTIN HAUT SERVICE). The health authority samples one tap per network; a network carries the same treated water everywhere.
More about this result
The US also limits PFOA and PFOS to 4 ng/L each, per substance.
Substances below the detection limit count as 0, so the real total may be higher.
One of these four, PFOA, is classified as causing cancer in humans by the WHO's cancer research agency (IARC).
More PFAS than in 95% of the cities we track
checked on 17 July 2026
20 PFAS (see each substance)
| PFAS substance | Value |
|---|---|
| Acide sulfonique de perfluorooctane (PFOS) | 0.005 µg/L |
| Acide perfluoropentanoïque (PFPEA) | 0.003 µg/L |
| Perfluorohexane sulfonate (PFHXS) | 0.003 µg/L |
| Acide perfluorohexanoïque (PFHXA) | 0.003 µg/L |
| Acide perfluoro-octanoïque (PFOA) | 0.001 µg/L |
| Acide perfluoro tridecanoique (PFTrDA) | <0,001 µg/L |
| Acide perfluorodecane sulfonique (PFDS) | <0,001 µg/L |
| Acide perfluoro tridecane sulfonique (PFTrDS) | <0,005 µg/L |
| Acide sulfonique de perfluorobutane (PFBS) | <0,001 µg/L |
| Acide perfluoropentane sulfonique (PFPS) | <0,001 µg/L |
| Acide perfluorobutanoïque (PFBA) | <0,002 µg/L |
| Acide perfluoro undecanoïque (PFUnA) | <0,001 µg/L |
| Acide perfluoro-nonanoïque (PFNA) | <0,001 µg/L |
| Acide perfluoro undecane sulfonique (PFUnDS) | <0,002 µg/L |
| Acide perfluorododécanoique (PFDoDA) | <0,001 µg/L |
| Acide perfluoroheptanoïque (PFHPA) | <0,001 µg/L |
| Acide perfluoro-decanoïque (PFDA) | <0,001 µg/L |
| Acide perfluoroheptane sulfonique (PFHpS) | <0,002 µg/L |
| Acide perfluorododécane sulfonique (PFDoDS) | <0,001 µg/L |
| Acide perfluorononane sulfonique (PFNS) | <0,002 µg/L |
Above our health benchmark. Here are some filter options.
- EU legal limit
- 15 ng/L sum of 20 PFAS, below the 100 ng/L limit
- Last PFAS test
- 17 July 2026
- Water supplier
- CA DU SAINT-QUENTINOIS
In Gauchy, the 4 most closely watched PFAS (PFAS-4) add up to 9 ng/L (0.009 µg/L) at the latest PFAS check on 17 July 2026. That's 18 times our 0.5 ng/L health benchmark, and above Sweden's legal limit of 4 ng/L. Sum of 20 PFAS: 15 ng/L (0.015 µg/L), below the EU legal limit (100 ng/L). Sampled in Fonsomme, on the same network. 5 checks since 5 January 2026: PFAS-4 up to 9 ng/L, sometimes below the detection limit, averaging 6.67 ng/L over 12 months. No clear trend. Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).
Details and sources
PFAS over time in Gauchy
8 PFAS checks since 27 January 2025, from the published measurements. Samples from 3 communes on the same network: it's the same water, so each one applies to Gauchy. Samples come from 3 distribution networks. The trend refers to the network “UDI SAINT QUENTIN HAUT SERVICE”.
“Calculated”: PFAS-4 worked out from the four substances in the same sample. The chart, averages and trends use lab-published sums only.
| Date | PFAS-4 | Sum of 20 PFAS | Sampled at | Network |
|---|---|---|---|---|
| 9 ng/L | 15 ng/L | Fonsomme | UDI SAINT QUENTIN HAUT SERVICE | |
| 3 ng/L | 11 ng/L | Saint-Quentin | UDI SAINT QUENTIN HAUT SERVICE | |
| 6 ng/L | 12 ng/L | Saint-Quentin | UDI SAINT QUENTIN BAS SERVICE | |
| < 4 ng/L | < 29 ng/L | Harly | UDI ST QUENTIN-HARLY | |
| 8 ng/L | 14 ng/L | Saint-Quentin | UDI SAINT QUENTIN HAUT SERVICE | |
| 9 ng/L – < 10 ng/L · calculated | 16 ng/L | Saint-Quentin | UDI SAINT QUENTIN HAUT SERVICE | |
| 1 ng/L – < 4 ng/L · calculated | 1 ng/L | Harly | UDI ST QUENTIN-HARLY | |
| 5 ng/L – < 7 ng/L · calculated | 7 ng/L | Saint-Quentin | UDI SAINT QUENTIN BAS SERVICE |
Calculated values: “<” is an upper bound from published thresholds, “≥” a lower bound, “–” means no published sum or complete measurement. How to read a PFAS result
What the latest check found
At the latest check, the water was within every limit tested.
Values to watch
These results are close to their legal limit, or over it.
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Nitrate | 46.6 mg/L | ≤ 50 mg/L | within the limit |
See all 17 test results
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Nitrate | 46.6 mg/L | ≤ 50 mg/L | within the limit |
| Nitrite | <0,010 mg/L | ≤ 0.5 mg/L | within the limit |
| Lead | 3 µg/L | ≤ 10 µg/L | within the limit |
| Copper | 0.021 mg(Cu)/L | ≤ 2 mg(Cu)/L | within the limit |
| Nickel | 1.1 µg/L | ≤ 20 µg/L | within the limit |
| Cadmium | <0,5 µg/L | ≤ 5 µg/L | within the limit |
| Chromium | 0.6 µg/L | ≤ 50 µg/L | within the limit |
| Escherichia coli | 0 n/(100mL) | ≤ 0 mL) | within the limit |
| Enterococci | 0 n/(100mL) | ≤ 0 mL) | within the limit |
| Coliform bacteria | 0 n/(100mL) | ≤ 0 mL) | within the limit |
| pH | 7.1 unité pH | 6.5–9 unité pH | within the limit |
| Water hardness | 31.3 °f | no limit | for reference |
| Electrical conductivity | 690 µS/cm | 200–1,100 µS/cm | within the limit |
| Chloride | 25.4 mg/L | ≤ 250 mg/L | within the limit |
| Sulphate | 19.3 mg/L | ≤ 250 mg/L | within the limit |
| Iron | <5 µg/L | ≤ 200 µg/L | within the limit |
| Turbidity | <0,30 NFU | ≤ 2 NFU | within the limit |
Frequently asked questions
Is tap water in Gauchy safe to drink?
Yes. At the check on 17 July 2026, the tap water in Gauchy was within every limit tested. “Eau d'alimentation conforme aux exigences de qualité en vigueur pour l'ensemble des paramètres mesurés. Présence de perchlorates >4 µg/l et <15 µg/l, la consommation de l'eau est déconseillée aux nourrissons d e moins de 6 mois.”
How high are PFAS levels in Gauchy's drinking water?
The total of 20 PFAS ("forever chemicals") was last measured at 15 ng/L. The EU limit is 100 ng/L, so this water is at 15 % of the limit. (below the EU limit)
Does the water in Gauchy also meet the strictest limits in Europe?
No. The four most harmful PFAS add up to 9 ng/L. That is 2.3 times Sweden's legal limit of 4 ng/L, in force since 2026. Germany will set a similar one in 2028. The water still passes the current EU legal limit (100 ng/L for the total of 20 PFAS).
Are PFAS levels rising in Gauchy's tap water?
No clear trend. Since 27 January 2025, 5 checks have been published; on the main network the PFAS-4 sum ranged between 3 ng/L and 9 ng/L (3 quantified values), at times below the detection limit. pfasnearme only reports a trend from a change of at least 25 % and 1 ng/L. These history statistics use laboratory-published sums only.
How hard is the water in Gauchy?
The water hardness in Gauchy is 31.3 °f (hard). This mainly matters for household appliances and detergent dosing, not for health.
Where does this data come from?
All values come from official publications: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM). Retrieved on 21 September 2026.
Same water network
Same distribution network as Gauchy, so in principle the same water.
Nearby communes
The closest to Gauchy on this site.
Data source
- Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM)
- https://hubeau.eaufrance.fr/api/v1/qualite_eau_potable/resultats_dis?code_commune=02340
- License
- Licence Ouverte / Open Licence (Etalab)
- Retrieved
- 21 September 2026
- Supply networks
- UDI ST QUENTIN-HARLY, UDI SAINT QUENTIN HAUT SERVICE, UDI SAINT QUENTIN BAS SERVICE
Water report for Gauchy
Get new PFAS results for Gauchy, with a short explanation. At most one update a week, only when there's something new.
This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.