Drinking water in Selzach
2 supply zones — values can differ depending on the district. Below is the zone with the most documented parameters, the others collapsed underneath. To determine the exact match, look up the postcode.
How to read the share of the parametric value
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.
Gruppenwasserversorgung Grenchen (GWVG)
SWGAssigned via the water supplier — the exact supply zone boundary within the postcode is not yet linked.
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Nitrate | 14 mg/l | 40 mg/l | 35 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Escherichia coli (E. coli) | nn not detectable Unit not stated in the document | 0/100 ml | — | Maximum · Median nn · Gruppenwasserversorgung Grenchen (GWVG) |
| Sulphate | 9.1 mg/l | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Sodium | 6.5 mg/l | 200 mg/l | 3 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
Show all recorded parameters (21 — most recent value per parameter)
Microbiology (3)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Aerobic mesophilic bacteria | 2 KBE/ml | 300 1/ml | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Escherichia coli (E. coli) | nn not detectable Unit not stated in the document | 0/100 ml | — | Maximum · Median nn · Gruppenwasserversorgung Grenchen (GWVG) |
| Intestinal enterococci | nn not detectable Unit not stated in the document | 0/100 ml | — | Maximum · Median nn · Gruppenwasserversorgung Grenchen (GWVG) |
Chemical parameters (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Fluoride | 0.053 mg/l | 1.5 mg/l | 4 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Nitrate | 14 mg/l | 40 mg/l | 35 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
PFAS (3)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Perfluorohexane sulfonic acid (PFHxS) | 0.001 µg/l | 0.3 µg/l | 0.3 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Perfluorooctanesulfonic acid (PFOS) | 0.001 µg/l | 0.3 µg/l | 0.3 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Perfluorooctanoic acid (PFOA) | < 0.001 µg/l below limit of quantification | 0.5 µg/l | < 0.2 % * | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
* 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.
Metabolites (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Chlorothalonil metabolite R417888 | 0.029 µg/l | 0.1 µg/l | 29 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Chlorothalonil metabolite R471811 | 0.22 µg/l | 0.1 µg/l | 220 % Mean above the parametric value | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
Annual means and medians are not individual measured values, but the parametric values apply per sample. If a mean lies above it, at least one individual sample was above it — the mean does not say how many, or by how much. That is why this is not reported here as an exceedance of the parametric value. What counts remains the water supplier's publication, which each row links to.
Indicator parameters (7)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Chloride | 7 mg/l | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Conductivity (25 °C) | 521 µS/cm | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| pH | 7.6 | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Sodium | 6.5 mg/l | 200 mg/l | 3 % | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Sulphate | 9.1 mg/l | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Temperature | 11.4 °C | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Turbidity | < 0.02 TE/F below limit of quantification | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
Further parameters (4)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Calcium | 89.2 mg/l | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Magnesium | 9.18 mg/l | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Potassium | 2.2 mg/l | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
| Total hardness | 25.7 °fH | — | — | Mean · Gruppenwasserversorgung Grenchen (GWVG) |
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.
Postcodes in this zone: 2545
Show 1 more supply zone
Wasserversorgung Grenchen (WVG)
SWGAssigned via the water supplier — the exact supply zone boundary within the postcode is not yet linked.
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Nitrate | 3.9 mg/l | 40 mg/l | 10 % | Mean · Wasserversorgung Grenchen (WVG) |
| Escherichia coli (E. coli) | nn not detectable Unit not stated in the document | 0/100 ml | — | Maximum · Median nn · Wasserversorgung Grenchen (WVG) |
| Sulphate | 9.5 mg/l | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Sodium | 1 mg/l | 200 mg/l | 0.5 % | Mean · Wasserversorgung Grenchen (WVG) |
Show all recorded parameters (20 — most recent value per parameter)
Microbiology (3)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Aerobic mesophilic bacteria | 1 KBE/ml | 300 1/ml | — | Mean · Wasserversorgung Grenchen (WVG) |
| Escherichia coli (E. coli) | nn not detectable Unit not stated in the document | 0/100 ml | — | Maximum · Median nn · Wasserversorgung Grenchen (WVG) |
| Intestinal enterococci | nn not detectable Unit not stated in the document | 0/100 ml | — | Maximum · Median nn · Wasserversorgung Grenchen (WVG) |
Chemical parameters (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Fluoride | 0.1 mg/l | 1.5 mg/l | 7 % | Mean · Wasserversorgung Grenchen (WVG) |
| Nitrate | 3.9 mg/l | 40 mg/l | 10 % | Mean · Wasserversorgung Grenchen (WVG) |
PFAS (3)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Perfluorohexane sulfonic acid (PFHxS) | < 0.001 µg/l below limit of quantification | 0.3 µg/l | < 0.3 % * | Mean · Wasserversorgung Grenchen (WVG) |
| Perfluorooctanesulfonic acid (PFOS) | < 0.001 µg/l below limit of quantification | 0.3 µg/l | < 0.3 % * | Mean · Wasserversorgung Grenchen (WVG) |
| Perfluorooctanoic acid (PFOA) | < 0.001 µg/l below limit of quantification | 0.5 µg/l | < 0.2 % * | Mean · Wasserversorgung Grenchen (WVG) |
* 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.
Metabolites (2)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Chlorothalonil metabolite R417888 | < 0.029 µg/l below limit of quantification | 0.1 µg/l | < 29 % * | Mean · Wasserversorgung Grenchen (WVG) |
| Chlorothalonil metabolite R471811 | < 0.22 µg/l below limit of quantification | 0.1 µg/l | cannot be assessed — the limit of quantification of the measurement is above the parametric value | Mean · Wasserversorgung Grenchen (WVG) |
* 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 (6)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Conductivity (25 °C) | 356 µS/cm | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| pH | 7.7 | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Sodium | 1 mg/l | 200 mg/l | 0.5 % | Mean · Wasserversorgung Grenchen (WVG) |
| Sulphate | 9.5 mg/l | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Temperature | 9.9 °C | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Turbidity | < 0.2 TE/F below limit of quantification | — | — | Mean · Wasserversorgung Grenchen (WVG) |
Further parameters (4)
| Parameter | Value | Parametric value | Share of the parametric value | Reference |
|---|---|---|---|---|
| Calcium | 61.5 mg/l | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Magnesium | 0.3 mg/l | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Potassium | 0.7 mg/l | — | — | Mean · Wasserversorgung Grenchen (WVG) |
| Total hardness | 18 °fH | — | — | Mean · Wasserversorgung Grenchen (WVG) |
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.
Postcodes in this zone: 2545
Frequently asked questions about drinking water in Selzach
- How hard is the water in Selzach?
- SWG publishes a total hardness of 25.7 °fH for the supply zone Gruppenwasserversorgung Grenchen (GWVG) — that corresponds to 14.4 °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 Selzach?
- SWG publishes a nitrate value of 14 mg/l for the supply zone Gruppenwasserversorgung Grenchen (GWVG). The statutory parametric value is 40 mg/l; the measured value represents 35 % of the parametric value. Basis: 2025, retrieved on 07/08/2026.
- Who supplies the drinking water in Selzach?
- SWG. The values shown here come from the supply zone Gruppenwasserversorgung Grenchen (GWVG) 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.