Water hardness and tap water in Wuppertal
Wuppertal, Nordrhein-Westfalen · Postcode 42103, 42107, 42109, 42113, 42119
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 (9), at the waterworks
- Water hardness11.3 °dH, mediumNo legal limit, only a range
- Data coverageCore parameters: 5 of 7Score based on complete data
Verified drinking-water values
Note from the test report (in the German original): Wasser und Abwasser Wuppertal (WAW) · Jahresmittelwerte 2025, Wasserwerk Benrath (Rheinuferfiltrat). Wuppertal bezieht außerdem aus den Talsperren-Wasserwerken Dabringhausen (Große Dhünn-Talsperre, sehr weich: 5,1 °dH) und Herbringhausen (Kerspe-/Herbringhauser Talsperre, 5,5 °dH) mit deutlich niedrigerem Nitrat (rund 7 mg/l) und PFAS-Werten unterhalb der Bestimmungsgrenze. Ein separates WAW-FAQ-Dokument nennt für Benrath abweichend rund 10,7 °dH und einen Mischwasser-Nitratdurchschnitt von 16 mg/l – beide Zahlen stammen aus offiziellen WAW-Quellen, vermutlich mit unterschiedlicher Berechnungsgrundlage.
Background on household plumbing, not a measurement: in Wuppertal, 65 % of buildings with living space were built before 1970, and a further 13 % 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 Wuppertal
- Nitrate 22 mg/L – about 44 % of the limit of 50 mg/L and comparatively high for a city waterworks; the cause is usually nitrate from agriculture entering the raw water. Boiling does not reduce nitrate.
- PFAS (sum of PFAS-20) 5 ng/L – about 5 % of the limit of 100 ng/L (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 0.5 µg/L – unremarkable against a limit of 10 µg/L. In some regions uranium occurs naturally from the rock (geogenic).
- pH 7.9 – 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 Wuppertal in everyday life
At 11.3 °dH, Wuppertal is in the hardness range “medium” (soft: below 8.4 °dH, medium: 8.4–14 °dH, hard: above 14 °dH).
- Dose detergent for the hardness range “medium”.
- As a rule of thumb, descale the kettle about every four to six weeks and the coffee machine as the manufacturer recommends.
- A limescale protection device is not a must at medium hardness; regular descaling is often enough.
Baby food and low sodium: tap water in Wuppertal 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 Wuppertal 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 Wuppertal |
|---|---|---|
| Sodium | 20 mg/l | 39.1 mg/l – above |
| Nitrate | 10 mg/l | 22 mg/l – above |
| Nitrite | 0.02 mg/l | not in the report |
| Sulphate | 240 mg/l | 70 mg/l – not above |
| Fluoride | 0.7 mg/l | not in the report |
| Manganese | 0.05 mg/l | not in the report |
| Arsenic | 0.005 mg/l | not in the report |
| Uranium | 0.002 mg/l | 0.0005 mg/l – not above |
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 Wuppertal
Can you drink the tap water in Wuppertal?
According to the verified values, yes: All tested parameters with a legal limit (9) meet the limits set by the German Drinking Water Ordinance (TrinkwV). WaterScore: 100 out of 100 (data coverage: 5 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 Wuppertal?
The total hardness is 11.3 °dH – hardness range “medium”. Dose detergent for the hardness range “medium”.
Is there PFAS in the tap water in Wuppertal?
Yes, in measurable amounts: according to the published analysis by Wasser und Abwasser Wuppertal (WAW) (as of 2025), the sum of PFAS-20 is 0.005 (middle of the range given by the supplier) µg/l – that is 5 % of the limit of 0.1 µg/l, which has applied since 12 January 2026.
Do I need to filter my tap water in Wuppertal?
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.
Is the nitrate level in Wuppertal a concern?
The value of 22 mg/L is below the limit of 50 mg/L, but higher than in many other evaluated cities. The limit of the Drinking Water Ordinance also applies to preparing baby food; mineral water labelled “suitable for preparing infant food” („geeignet für die Zubereitung von Säuglingsnahrung“) may contain at most 10 mg/L nitrate. Boiling does not help against nitrate.
WaterScore
- Total100 / 100
- Chemical safety100 / 100
- Heavy metals100 / 100
- PFAS100 / 100
- Nutrients100 / 100
- General parameters100 / 100
- Data timeliness100 / 100
- Data quality100 / 100
Data coverage: 5 of 7 core parameters. Not in the test report: Nitrite and Arsenic. 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 Wuppertal, Wasserwerk Benrath (Rheinuferfiltrat), Jahresmittelwerte 2025 (Eigenbetrieb Wasser und Abwasser Wuppertal (WAW)) · SHA-256 of the evaluated file: 03bbd39ca79ce675…, checked on 3 October 2026
Suggested citation: Trinkwassermonitor (2025): Tap water in Wuppertal. Values according to the water supplier’s test report, sampling date 2025; at the waterworks, not household plumbing. https://trinkwassermonitor.ink/en/tap-water/wuppertal/
JSON: /api/v1/evidence?city=wuppertal
Data as of: 2025 · verified: 13 of 13 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 Wuppertal. Retrieved from https://trinkwassermonitor.ink/en/tap-water/wuppertal/.”