How hard is the water in Wittenwil?

EW Aadorf publishes a total hardness of 42.5 °fH for the supply zone Wittenwil — that corresponds to 23.8 °dH. The hardness range is a classification under the German Detergents and Cleaning Products Act (soft below 8,4 °dH, medium 8,4 to 14 °dH, hard above that) and not a quality verdict — it indicates how much calcium and magnesium is dissolved in the water. Basis: 2025, retrieved on 07/08/2026.

How much nitrate is in the drinking water in Wittenwil?

EW Aadorf publishes a nitrate value of 31.1 mg/l for the supply zone Wittenwil. The statutory parametric value is 40 mg/l; the measured value represents 78 % of the parametric value. Basis: 2025, retrieved on 07/08/2026.

Who supplies the drinking water in Wittenwil?

EW Aadorf. The values shown here come from the supply zone Wittenwil and apply to the water the supplier delivers. What happens between the building connection and the tap — in old lead pipes, for example — is not covered by these analyses; information on that is provided by owners, the health authority or an examination by an accredited laboratory.

Drinking water in Wittenwil

One supply zone, water supplier: EW Aadorf.

How to read the share of the parametric value

12 % Share of the parametric value. The proportion of the permitted maximum that the measured value uses — here 12 %, so just over an eighth.

< 10 % * Below the limit of quantification. The substance was not detectable. The mark shows where the detection limit lies relative to the parametric value — the actual share of the parametric value is below that.

Several samples per year: for chemical parameters the mean value is given, for microbiological ones the highest measured value. There the parametric value is zero — a single finding would disappear in the average, and it is precisely that finding which is the information. Which reference applies is stated in the last column of the table.

Wittenwil

EW Aadorf

Assigned via the water supplier — the exact supply zone boundary within the postcode is not yet linked.

Water hardness

23.8 °dH

Hardness range hard

Key values Wittenwil
Parameter	Value	Parametric value	Share of the parametric value	Reference
Nitrate	31.1 mg/l	40 mg/l	78 %	Mean · Wittenwil
Escherichia coli (E. coli)	nn not detectable Unit not stated in the document	0/100 ml	—	Maximum · Median nn · Wittenwil
Sulphate	8.4 mg/l	—	—	Mean · Wittenwil
Sodium	6.71 mg/l	200 mg/l	3 %	Mean · Wittenwil

Show all recorded parameters (15 — most recent value per parameter)

Microbiology (3)

Microbiology – Wittenwil
Parameter	Value	Parametric value	Share of the parametric value	Reference
Aerobic mesophilic bacteria	62.4 KBE/ml	300 1/ml	—	Mean · Wittenwil
Escherichia coli (E. coli)	nn not detectable Unit not stated in the document	0/100 ml	—	Maximum · Median nn · Wittenwil
Intestinal enterococci	nn not detectable Unit not stated in the document	0/100 ml	—	Maximum · Median nn · Wittenwil

Chemical parameters (1)

Chemical parameters – Wittenwil
Parameter	Value	Parametric value	Share of the parametric value	Reference
Nitrate	31.1 mg/l	40 mg/l	78 %	Mean · Wittenwil

Metabolites (2)

Metabolites – Wittenwil
Parameter	Value	Parametric value	Share of the parametric value	Reference
Chlorothalonil metabolite R417888	< 0.02 µg/l below limit of quantification	0.1 µg/l	< 20 % *	Mean · Wittenwil
Chlorothalonil metabolite R471811	0.02 µg/l	0.1 µg/l	20 %	Mean · Wittenwil

* Value below the limit of quantification: the actual share of the parametric value is not known; it lies somewhere below the stated upper bound. The marker shows where the limit of quantification of the measurement lies relative to the parametric value.

Indicator parameters (5)

Indicator parameters – Wittenwil
Parameter	Value	Parametric value	Share of the parametric value	Reference
Chloride	9.49 mg/l	—	—	Mean · Wittenwil
pH	7.48	—	—	Mean · Wittenwil
Sodium	6.71 mg/l	200 mg/l	3 %	Mean · Wittenwil
Sulphate	8.4 mg/l	—	—	Mean · Wittenwil
Temperature	18.3 °C	—	—	Mean · Wittenwil

Further parameters (4)

Further parameters – Wittenwil
Parameter	Value	Parametric value	Share of the parametric value	Reference
Calcium	117.05 mg/l	—	—	Mean · Wittenwil
Magnesium	32.3 mg/l	—	—	Mean · Wittenwil
Potassium	1.53 mg/l	—	—	Mean · Wittenwil
Total hardness	42.5 °fH	—	—	Mean · Wittenwil

Values taken unchanged from the publications linked below — for each parameter the most recent recorded value. „—" in the parametric value column: no currently valid legal parametric value is stored in our database for this parameter; the parameter register with all parametric values is being expanded continuously.

Source: https://trinkwasser.ch/de/versorger/871/ew-aadorf/3447/wittenwil · 2025 · 2025 · retrieved on 07/08/2026

Postcodes in this zone: 9547

Frequently asked questions about drinking water in Wittenwil

How hard is the water in Wittenwil?: EW Aadorf publishes a total hardness of 42.5 °fH for the supply zone Wittenwil — that corresponds to 23.8 °dH. The hardness range is a classification under the German Detergents and Cleaning Products Act (soft below 8,4 °dH, medium 8,4 to 14 °dH, hard above that) and not a quality verdict — it indicates how much calcium and magnesium is dissolved in the water. Basis: 2025, retrieved on 07/08/2026.
How much nitrate is in the drinking water in Wittenwil?: EW Aadorf publishes a nitrate value of 31.1 mg/l for the supply zone Wittenwil. The statutory parametric value is 40 mg/l; the measured value represents 78 % of the parametric value. Basis: 2025, retrieved on 07/08/2026.
Who supplies the drinking water in Wittenwil?: EW Aadorf. The values shown here come from the supply zone Wittenwil and apply to the water the supplier delivers. What happens between the building connection and the tap — in old lead pipes, for example — is not covered by these analyses; information on that is provided by owners, the health authority or an examination by an accredited laboratory.

General questions — how current the data is, limit of quantification, parametric values, who is behind this site — are answered under Questions & answers.