Water hardness and tap water in Rosenheim
Rosenheim, Bayern · Postcode 83022, 83024, 83026
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 (17), at the waterworks
- Water hardness18.3 °dH, hardNo legal limit, only a range
- Data coverageCore parameters: 7 of 7Score based on complete data
Verified drinking-water values
Note from the test report (in the German original): DAkkS-akkreditierter Prüfbericht (SWM Services GmbH, PFAS/Pestizide via ALS Germany GmbH), Probenahme 07.07.2026 am Hochbehälter Kreut, Kammer 1, fertiggestellt 31.07.2026. Rosenheim wird zusätzlich aus dem Hochbehälter Waldering 820 versorgt, der ähnliche, leicht abweichende Werte liefert (Gesamthärte 19,2 °dH gegenüber 18,3 °dH in Kreut; Stand 14.10.2025, eigener Prüfbericht) – der Wert für eine konkrete Adresse hängt vom Versorgungsgebiet ab.
Background on household plumbing, not a measurement: in Rosenheim, 40 % of buildings with living space were built before 1970, and a further 18 % 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 Rosenheim
- Nitrate 9.6 mg/L – about 19 % 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.
- Lead – not detectable at the waterworks. Lead gets into the water almost only through old lead pipes in household plumbing, not via the supplier.
- Uranium 1 µg/L – unremarkable against a limit of 10 µg/L. In some regions uranium occurs naturally from the rock (geogenic).
- pH 7.26 – 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 Rosenheim in everyday life
At 18.3 °dH, Rosenheim 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 Rosenheim 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 Rosenheim 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)
| Substance | Maximum level | Value in Rosenheim |
|---|---|---|
| Sodium | 20 mg/l | 9.5 mg/l – not above |
| Nitrate | 10 mg/l | 9.6 mg/l – not above |
| Nitrite | 0.02 mg/l | below the detection limit (0.05 mg/l) – cannot be assessed |
| Sulphate | 240 mg/l | 25.3 mg/l – not above |
| Fluoride | 0.7 mg/l | below the detection limit (0.2 mg/l) – not above |
| Manganese | 0.05 mg/l | below the detection limit (0.005 mg/l) – not above |
| Arsenic | 0.005 mg/l | below the detection limit (0.0004 mg/l) – not above |
| Uranium | 0.002 mg/l | 0.001 mg/l – not above |
Against the other thresholds of Annex 6, the water would qualify as: low in sodium (“suitable for a low-sodium diet”) (Sodium 9.5 mg/l, threshold below 20 mg/l).
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. Questions about baby food are answered by your midwife, your paediatrician and the health office (Gesundheitsamt).
Frequently asked questions about tap water in Rosenheim
Can you drink the tap water in Rosenheim?
According to the verified values, yes: All tested parameters with a legal limit (17) meet the limits set by the German Drinking Water Ordinance (TrinkwV). WaterScore: 100 out of 100 (data coverage: 7 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 Rosenheim?
The total hardness is 18.3 °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 Rosenheim?
Not in measurable amounts: according to the published analysis by Stadtwerke Rosenheim GmbH & Co. KG (as of 7 July 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. This means the sum of the four substances PFOA, PFOS, PFNA and PFHxS (PFAS-4) is also below the limit of 0.02 µg/l, which applies from 12 January 2028.
Do I need to filter my tap water in Rosenheim?
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: 7 of 7 core parameters. 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 v3: how we calculate the WaterScore.
Evidence: cite and check
- Trinkwasseranalyse Hochbehälter Kreut, Kammer 1 (Probe 2026063262) (Stadtwerke Rosenheim GmbH & Co. KG (Prüfbericht: SWM Services GmbH / ALS Germany GmbH)) · SHA-256 of the evaluated file: fef0e36e14ae18d1…, checked on 3 October 2026
Suggested citation: Trinkwassermonitor (2026): Tap water in Rosenheim. Values according to the water supplier’s test report, sampling date 7 July 2026; at the waterworks, not household plumbing. https://trinkwassermonitor.ink/en/tap-water/rosenheim/
JSON: /api/v1/evidence?city=rosenheim
Data as of: 7 July 2026 · verified: 22 of 22 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 Rosenheim. Retrieved from https://trinkwassermonitor.ink/en/tap-water/rosenheim/.”