Water hardness in Overath
9.7 °dH hard
Tap water in Overath is hard: 9.7 °dH (173 mg/L · 10.1 gpg · 17.3 °fH).
Source: RheinEnergie BELKAW Trinkwasseranalyse, Jahresmittelwerte 2025 (linked from Stadtwerke Overath) (2025) · data checked 2026-10-23
Range across supply zones: 117–229 mg/L.
2 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °dH | mg/L | ||
|---|---|---|---|
| RheinEnergie BELKAW (Lieferant) | 12.8 | 229 | very hard |
| Stadtwerke Rösrath (Lieferant) | 6.5 | 117 | moderately hard |
Overath is supplied by several sources through the Stadtwerke network, so there is no single citywide figure. The RheinEnergie BELKAW share is 228.5 mg/L CaCO₃ (2025 annual mean) and the Rösrath share is 116.9 mg/L, while the Aggerverband and Lohmar shares are only labelled soft without numbers. Ask Stadtwerke Overath which supplier serves your address.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 9.7 °dH |
|---|---|
| Utility | Stadtwerke Overath (Netz); Wasser von Aggerverband, RheinEnergie BELKAW, Stadtwerke Rösrath, Stadtwerke Lohmar |
How Overath compares
- Tap water in Overath is 16 % softer than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 494 of 809 in Germany (1 = hardest); 39 % of these cities have softer water.
- In Nordrhein-Westfalen it is number 97 of 153 cities; the regional median is 11.3 °dH.
- Nearest city with clearly softer water: Rösrath, 8 km away (6.5 °dH).
- Nearest city with clearly harder water: Cologne, 23 km away (16.9 °dH).
Ranking of the hardest and softest water in Germany →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Overath
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 10 °dH |
| AEG / Electrolux | 2 |
| Beko | 3rd |
| Hoover | S1 |
| LG | H2 |
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 Overath water hard or soft?
It is hard: 173 mg/L as CaCO₃ (10.1 gpg, 9.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Overath 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 Overath water?
10.1 gpg, equal to 9.7 °dH, 17.3 °fH or 173 mg/L calcium carbonate.
What dishwasher salt setting should I use in Overath?
For 173 mg/L (9.7 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Overath?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: RheinEnergie BELKAW Trinkwasseranalyse, Jahresmittelwerte 2025 (linked from Stadtwerke Overath) (2025). Method: figure published by the water supplier. RheinEnergie BELKAW Trinkwasseranalyse, Jahresmittelwerte 2025 (linked from Stadtwerke Overath) · Outdated figure? Tell us