Water hardness and tap water in Potsdam

Name: Water hardness and tap water in Potsdam
Creator: Trinkwassermonitor
License: https://creativecommons.org/licenses/by/4.0/

Potsdam, Brandenburg · Postcode 14467, 14469, 14471, 14473, 14476, 14478 …

This page is a translation of the German version; the German page is authoritative. German version · Report a translation error

Short answer: The tap water in Potsdam has a total hardness of 14.1 °dH, hardness range “hard” (as of 24 July 2025). All tested parameters with a legal limit (15) meet the limits set by the German Drinking Water Ordinance (TrinkwV). Source: test report by EWP. WaterScore: 99.3 out of 100 (data coverage: 7 of 7 core parameters).

Limits of the Drinking Water OrdinancemetAll tested parameters (15), at the waterworks
Water hardness14.1 °dH, hardNo legal limit, only a range
Data coverageCore parameters: 7 of 7Score based on complete data

Verified drinking-water values

Parameter	Value	Limit (TrinkwV)	Sampling date	Source	Status
Nitrate	1.6 mg/L	50 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Nitrite	< 0.03 mg/L	0.5 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
PFAS (sum)	< 0.001 µg/L	0.1 µg/L in force since 12 January 2026 from 12 January 2028: additionally PFAS-4 0.02 µg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Lead	< 0.0003 mg/L	0.01 mg/L from 12 January 2028: 0.005 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Arsenic	< 0.0003 mg/L	0.01 mg/L new plants from 2028, all from 2036: 0.004 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Uranium	0.0006 mg/L	0.01 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Mercury	< 0.0001 mg/L	0.001 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Copper	< 0.001 mg/L	2 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Cadmium	< 0.0001 mg/L	0.003 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Chromium	< 0.0001 mg/L	0.025 mg/L from 12 January 2030: 0.005 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Nickel	< 0.0005 mg/L	0.02 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Chloride	70 mg/L 28 % of the limit	250 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Sulphate	80 mg/L 32 % of the limit	250 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Sodium	45 mg/L 23 % of the limit	200 mg/L	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Calcium	90 mg/L	–	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Magnesium	8.5 mg/L	–	24 July 2025	Energie und Wasser Potsdam GmbH	verified
pH	7.7	6.5–9.5	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Total hardness	14.1 °dH (hard)	no legal limit	24 July 2025	Energie und Wasser Potsdam GmbH	verified
Electrical conductivity	675 µS/cm	–	24 July 2025	Energie und Wasser Potsdam GmbH	verified

Note from the test report (in the German original): EWP · Analysenwerte Stand 24.07.2025 für das Wasserwerk Leipziger Straße (versorgt u. a. die südliche Innenstadt/Zentrum Ost). Potsdam wird aus fünf Wasserwerken versorgt (Leipziger Straße, Wildpark, Nedlitz, Rehbrücke, Ferch); die Gesamthärte reicht von 10,6 °dH (Ferch, mittel) bis 20,5 °dH (Wildpark, hart) – vier der fünf Werke liegen im Härtebereich hart. Beim Wasserwerk Nedlitz liegt die Summe PFAS-20 mit 0,000017 mg/l (17 % des ab 2026 geltenden Grenzwerts) höher als in den übrigen Potsdamer Werken.

Is a value wrong or out of date? Report an error – we check every report against the original source.

Water at your own tap: The values describe the water the supplier delivers – not automatically the water at your tap. The water supplier is responsible up to the service connection (Hausanschluss); the building owner is responsible for the pipes beyond it. Lead can dissolve from lead pipes, leaded solder joints or old brass fittings, especially when water has stood in the pipes for a long time (stagnant water); this mainly affects buildings constructed before about 1973. If water has stood in the pipes for several hours, let it run until it comes out cool. If you suspect lead pipes, a lead analysis of the stagnant water by an accredited laboratory will help.

Background on household plumbing, not a measurement: in Potsdam, 41 % of buildings with living space were built before 1970, and a further 6 % 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 Potsdam

Nitrate 1.6 mg/L – about 3 % 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 0.6 µg/L – unremarkable against a limit of 10 µg/L. In some regions uranium occurs naturally from the rock (geogenic).
pH 7.7 – 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 Potsdam in everyday life

At 14.1 °dH, Potsdam 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 Potsdam 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 Potsdam 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)

Values at the waterworks next to the maximum levels for bottled water “suitable for infant food”
Substance	Maximum level	Value in Potsdam
Sodium	20 mg/l	45 mg/l – above
Nitrate	10 mg/l	1.6 mg/l – not above
Nitrite	0.02 mg/l	below the detection limit (0.03 mg/l) – cannot be assessed
Sulphate	240 mg/l	80 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	below the detection limit (0.0003 mg/l) – not above
Uranium	0.002 mg/l	0.0006 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 Potsdam

Can you drink the tap water in Potsdam?

According to the verified values, yes: All tested parameters with a legal limit (15) meet the limits set by the German Drinking Water Ordinance (TrinkwV). WaterScore: 99.3 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 Potsdam?

The total hardness is 14.1 °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 Potsdam?

Not in measurable amounts: according to the published analysis by EWP (as of 24 July 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. 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 Potsdam?

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

Total99.3 / 100
Chemical safety100 / 100
Heavy metals100 / 100
PFAS100 / 100
Nutrients100 / 100
General parameters100 / 100
Data timeliness95.1 / 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 – Analysenwerte des Trinkwassers im Versorgungsbereich Potsdam, Ausgang Wasserwerke, Stand 24.07.2025 (Energie und Wasser Potsdam GmbH) · SHA-256 of the evaluated file: 9132e5e35ef92259…, checked on 3 October 2026

Suggested citation: Trinkwassermonitor (2025): Tap water in Potsdam. Values according to the water supplier’s test report, sampling date 24 July 2025; at the waterworks, not household plumbing. https://trinkwassermonitor.ink/en/tap-water/potsdam/

JSON: /api/v1/evidence?city=potsdam

Data as of: 24 July 2025 · verified: 19 of 19 evaluated parameters. (older than twelve months – under § 46 TrinkwV your supplier must publish current values online)

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 Potsdam. Retrieved from https://trinkwassermonitor.ink/en/tap-water/potsdam/.”