Water hardness in Röttgen
6.2 °dH moderately hard
Tap water in Röttgen is moderately hard: 6.2 °dH (111 mg/L · 6.5 gpg · 11.1 °fH).
Source: SWB Energie und Wasser Wasseranalyse Bonn, Mittelwerte 2020 (2020) · data checked 2026-11-06
This figure is over 3 years old; hardness may have changed.
For Röttgen we only have a value of 110.7 mg/L from the 2020 averages published by SWB Energie und Wasser (Stadtwerke Bonn). It is a supply-area figure covering several districts, not Röttgen alone, and it is outdated. For a current figure at your address, ask the utility directly.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 6.2 °dH |
|---|---|
| Utility | SWB Energie und Wasser (Stadtwerke Bonn) |
How Röttgen compares
- Tap water in Röttgen is 46 % softer than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 689 of 809 in Germany (1 = hardest); 15 % of these cities have softer water.
- In Nordrhein-Westfalen it is number 134 of 153 cities; the regional median is 11.3 °dH.
- Nearest city with clearly softer water: Siegburg, 17 km away (4.8 °dH).
- Nearest city with clearly harder water: Bornheim (Rhein-Sieg), 11 km away (12 °dH).
Ranking of the hardest and softest water in Germany →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Röttgen
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 6 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H1 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Röttgen water hard or soft?
It is moderately hard: 111 mg/L as CaCO₃ (6.5 gpg, 6.2 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Röttgen safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
How many grains per gallon is Röttgen water?
6.5 gpg, equal to 6.2 °dH, 11.1 °fH or 111 mg/L calcium carbonate.
What dishwasher salt setting should I use in Röttgen?
For 111 mg/L (6.2 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Röttgen?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: SWB Energie und Wasser Wasseranalyse Bonn, Mittelwerte 2020 (2020). Method: older figure, source currently unavailable. SWB Energie und Wasser Wasseranalyse Bonn, Mittelwerte 2020 · Outdated figure? Tell us