Water hardness in Frechen
16.3 °dH very hard
Tap water in Frechen is very hard: 16.3 °dH (291 mg/L · 17 gpg · 29.1 °fH).
Source: RheinEnergie AG Trinkwasseranalyse Frechen Mischwasser (Ausgabe 2026) (2025) · data checked 2026-10-20
RheinEnergie AG publishes a mixed-water analysis for Frechen, combining the Türnich waterworks with a RheinEnergie waterworks (2026 edition). It reports 291.0 mg/L CaCO₃. The figure describes the blended supply, not individual streets. Limescale on heating elements and glass is likely.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 16.3 °dH |
|---|---|
| Utility | RheinEnergie AG |
How Frechen compares
- Tap water in Frechen is 42 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 211 of 809 in Germany (1 = hardest); 74 % of these cities have softer water.
- In Nordrhein-Westfalen it is number 19 of 153 cities; the regional median is 11.3 °dH.
- Nearest city with clearly softer water: Hürth, 5 km away (10.1 °dH).
- Nearest city with clearly harder water: Limburg an der Lahn, 104 km away (23.3 °dH).
Ranking of the hardest and softest water in Germany →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Frechen
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 16 °dH |
| AEG / Electrolux | 4 |
| Beko | 5th |
| Hoover | S2 |
| LG | H3 |
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 Frechen water hard or soft?
It is very hard: 291 mg/L as CaCO₃ (17 gpg, 16.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Frechen 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 Frechen water?
17 gpg, equal to 16.3 °dH, 29.1 °fH or 291 mg/L calcium carbonate.
What dishwasher salt setting should I use in Frechen?
For 291 mg/L (16.3 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Frechen?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: RheinEnergie AG Trinkwasseranalyse Frechen Mischwasser (Ausgabe 2026) (2025). Method: figure published by the water supplier. RheinEnergie AG Trinkwasseranalyse Frechen Mischwasser (Ausgabe 2026) · Outdated figure? Tell us