Water hardness and tap water in Ettlingen
Landkreis Karlsruhe, Baden-Württemberg · Postcode 76275
This page is a translation of the German version; the German page is authoritative. German version · Report a translation error
- Limits of the Drinking Water OrdinancemetAll tested parameters (7), at the waterworks
- Water hardness17.3 °dH, hardNo legal limit, only a range
- Data coverageCore parameters: 4 of 7Score based on complete data
Verified drinking-water values
Note from the test report (in the German original): Trinkwasseranalyse 2026 der Stadtwerke, Analysewerte vom 16.03.2026, ermittelt vom TZW Karlsruhe. Die Werte stehen in der Spalte „Kernstadt und alle Stadtteile“; das Wasser kommt laut Stadtwerken aus dem Wasserwerk Rheinwald. Die Härte nennt die Broschüre für alle Stadtteile mit 3,09 mmol/l. Sie weist bei mehreren Stoffen nur „< BG“ ohne Zahl aus, Summe PFAS-20 und PFAS-4 mit 0,00 µg/l. Blei, Arsen, Uran und mikrobiologische Werte fehlen im Dokument. Blei und Kupfer können im eigenen Haus abweichen.
Background on household plumbing, not a measurement: in Ettlingen, 42 % of buildings with living space were built before 1970, and a further 20 % between 1970 and 1979 (Zensus 2022, Statistisches Bundesamt, dl-de/by-2-0). (Zensus 2022) According to the German Environment Agency (Umweltbundesamt), lead pipes exist at most in houses built before 1973 – and by no means in all of them. Whether there are any in your house is known to the owner or a plumber. (UBA)
What the values mean for Ettlingen
- Nitrate 2 mg/L – about 4 % of the limit of 50 mg/L and in the unremarkable range. Boiling does not reduce nitrate.
- PFAS (sum of PFAS-20) – not detectable in the sample evaluated. The limit of 0.1 µg/L (100 ng/L) has applied since 12 January 2026.
- pH 7.31 – within the range of the Drinking Water Ordinance (6.5 to 9.5). The pH determines how corrosive the water is in household plumbing.
Water hardness in Ettlingen in everyday life
At 17.3 °dH, Ettlingen is in the hardness range “hard” (soft: below 8.4 °dH, medium: 8.4–14 °dH, hard: above 14 °dH).
- Dose detergent for the hardness range “hard” – a larger amount is needed; a water softener for the washing machine can save detergent.
- Limescale builds up quickly: descale the kettle about every two to three weeks, and taps and shower heads too.
- In your own house, limescale protection or a water softener can be worthwhile at this hardness; in a rented flat, the owner decides.
Baby food and low sodium: tap water in Ettlingen next to the bottled-water thresholds
Bottled water may only be labelled “suitable for preparing infant food” („geeignet für die Zubereitung von Säuglingsnahrung“) if it keeps to the maximum levels of the German Mineral and Table Water Ordinance (Mineral- und Tafelwasser-Verordnung, Annex 6). Here the published values for Ettlingen are shown next to them, each substance on its own. This is a comparison with labelling thresholds for bottled water, not a statement on whether your tap water is suitable for baby food. (Min/TafelWV, Anlage 6)
For context: the German Environment Agency (Umweltbundesamt) considers preparing baby food with bottled water carrying this label necessary only in rare cases, for example when tap water is temporarily allowed to contain more than 50 mg/l nitrate. (UBA 2016, p. 59) Water from lead pipes in the house is always unsuitable for infants. (UBA 2020, p. 16) The values apply at the waterworks.
| Substance | Maximum level | Value in Ettlingen |
|---|---|---|
| Sodium | 20 mg/l | 9.3 mg/l – not above |
| Nitrate | 10 mg/l | 2 mg/l – not above |
| Nitrite | 0.02 mg/l | below the limit of quantification – cannot be assessed |
| Sulphate | 240 mg/l | 38.7 mg/l – not above |
| Fluoride | 0.7 mg/l | not in the report |
| Manganese | 0.05 mg/l | below the limit of quantification – cannot be assessed |
| Arsenic | 0.005 mg/l | not in the report |
| Uranium | 0.002 mg/l | not in the report |
Against the other thresholds of Annex 6, the water would qualify as: low in sodium (“suitable for a low-sodium diet”) (Sodium 9.3 mg/l, threshold below 20 mg/l).
Questions about baby food are answered by your midwife, your paediatrician and the health office (Gesundheitsamt).
Frequently asked questions about tap water in Ettlingen
Can you drink the tap water in Ettlingen?
According to the verified values, yes: All tested parameters with a legal limit (7) meet the limits set by the German Drinking Water Ordinance (TrinkwV). WaterScore: 100 out of 100 (data coverage: 4 of 7 core parameters). This applies to the water from the waterworks – restrictions can only arise from old household plumbing.
How hard is the water in Ettlingen?
The total hardness is 17.3 °dH – hardness range “hard”. Dose detergent for the hardness range “hard” – a larger amount is needed; a water softener for the washing machine can save detergent.
Is there PFAS in the tap water in Ettlingen?
Not in measurable amounts: according to the published analysis by Stadtwerke Ettlingen (as of 16 March 2026), PFAS were below the laboratory’s limit of quantification. Since 12 January 2026, a limit of 0.1 µg/l has applied to the sum of PFAS-20.
Do I need to filter my tap water in Ettlingen?
Based on the verified supplier values, a filter is not necessary. It can make sense if you do not like the taste. If you suspect lead pipes in an old building, a filter does not help; a laboratory analysis at the tap does – that is a question of the household plumbing, not of the water leaving the works.
WaterScore
- Total100 / 100
- Chemical safety100 / 100
- Heavy metals100 / 100
- PFAS100 / 100
- Nutrients100 / 100
- General parameters100 / 100
- Data timeliness100 / 100
- Data quality100 / 100
Data coverage: 4 of 7 core parameters. Not in the test report: Lead, Arsenic and Uranium. Missing parameters are neither estimated nor counted as harmless: the score is based only on the values available. It is not a health assessment and says nothing about the water beyond the service connection. Methodology v4: how we calculate the WaterScore.
Evidence: cite and check
- Trinkwasseranalyse 2026, Analysewerte vom 16.03.2026 (Stadtwerke Ettlingen GmbH (Analyse: TZW Technologiezentrum Wasser, Karlsruhe)) · SHA-256 of the evaluated file: 9fe2794d19c5c078…, checked on 1 November 2026
Suggested citation: Trinkwassermonitor (2026): Tap water in Ettlingen. Values according to the water supplier’s test report, sampling date 16 March 2026; at the waterworks, not household plumbing. https://trinkwassermonitor.ink/en/tap-water/ettlingen/
JSON: /api/v1/evidence?city=ettlingen
Data as of: 16 March 2026 · verified: 15 of 15 evaluated parameters.
This page shows only verified test data with sources, or states explicitly where data is missing (no estimated values). Cite as: “Trinkwassermonitor (2026). Tap water in Ettlingen. Retrieved from https://trinkwassermonitor.ink/en/tap-water/ettlingen/.”