Water hardness and tap water in Paderborn
Paderborn, Nordrhein-Westfalen · Postcode 33098, 33100, 33102, 33104, 33106
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 (12), at the waterworks
- Water hardness14.4 °dH, hardNo 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): Wasserwerke Paderborn GmbH (Geschäftsbesorgung: Stadtwerke Paderborn) · Referenzanalysen 2026 (Basis: Analysen 2025), Wasserwerk Diebesweg – eines von fünf Paderborner Wasserwerken. Die übrigen vier zeigen deutlich unterschiedliche Härte: Boker Heide am härtesten (17,1 °dH), Hossengrund (5,86 °dH) und Lichtenau (5,68 °dH) am weichsten, Aabach dazwischen (7,71 °dH). Alle fünf Werke melden Summe PFAS-20 unterhalb der Bestimmungsgrenze von 0,0001 mg/l (0,10 µg/l); beim Werk Aabach druckt das Original-PDF hierfür abweichend '<0,001 mg/l' statt '<0,0001 mg/l' wie bei den anderen vier Werken – möglicherweise ein Tippfehler des Versorgers, hier wortgetreu übernommen statt stillschweigend korrigiert. Trihalomethane werden in diesem Dokument nicht separat ausgewiesen.
Background on household plumbing, not a measurement: in Paderborn, 35 % of buildings with living space were built before 1970, and a further 16 % 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 Paderborn
- Nitrate 12 mg/L – about 24 % of the limit of 50 mg/L and in the medium range – such values occur in catchments shaped by agriculture. 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 – not detectable at the waterworks (limit 10 µg/L).
- pH 7.64 – 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 Paderborn in everyday life
At 14.4 °dH, Paderborn 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 Paderborn 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 Paderborn 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 Paderborn |
|---|---|---|
| Sodium | 20 mg/l | 6.2 mg/l – not above |
| Nitrate | 10 mg/l | 12 mg/l – above |
| Nitrite | 0.02 mg/l | not in the report |
| Sulphate | 240 mg/l | 23 mg/l – not above |
| Fluoride | 0.7 mg/l | below the detection limit (0.1 mg/l) – not above |
| Manganese | 0.05 mg/l | below the detection limit (0.005 mg/l) – not above |
| Arsenic | 0.005 mg/l | not in the report |
| Uranium | 0.002 mg/l | below the detection limit (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 6.2 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 Paderborn
Can you drink the tap water in Paderborn?
According to the verified values, yes: All tested parameters with a legal limit (12) 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 Paderborn?
The total hardness is 14.4 °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 Paderborn?
Not in measurable amounts: according to the published analysis by Wasserwerke Paderborn (Stadtwerke Paderborn) (as of 2025), 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 Paderborn?
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: 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
- Trinkwasserqualität Paderborn, Referenzanalysen 2026, Wasserwerk Diebesweg (Wasserwerke Paderborn GmbH (Geschäftsbesorgung: Stadtwerke Paderborn GmbH)) · SHA-256 of the evaluated file: 38f829738dc80648…, checked on 3 October 2026
Suggested citation: Trinkwassermonitor (2025): Tap water in Paderborn. Values according to the water supplier’s test report, sampling date 2025; at the waterworks, not household plumbing. https://trinkwassermonitor.ink/en/tap-water/paderborn/
JSON: /api/v1/evidence?city=paderborn
Data as of: 2025 · verified: 18 of 18 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 Paderborn. Retrieved from https://trinkwassermonitor.ink/en/tap-water/paderborn/.”