DE65 Derby
Harder than the UK average. Expect visible limescale on kettles and taps.
At 198 ppm, Derby sits among the UK's hardest water areas — compare it against the softest areas.
What this means for your home
Based on 198 ppm in Derby (hard water).
- Significant limescale buildup in kettles, pipes and boilers
- Soap scum on shower screens and taps
- Higher energy bills from scale in heating elements
- Dry skin and dull hair after washing
- White residue on dishes and glassware
Should you soften the water in Derby?
A verdict and running-cost estimate based on DE65's 198 ppm reading, for a typical 4-person household.
Hardness is moderate to hard, so a softener cuts scale and soap use and usually pays back over its lifetime.
Appliance impact at 198 ppm: slight: minor descaling extends kettle/boiler life. Sized for a 4-person home; regenerates roughly every 14 days (estimate). Figures are conservative estimates and vary with household size and usage.
Hardness data for DE65
Sourced from Severn Trent Water's published water-quality reports and public records.
Hardness measurements
| Parts per million (ppm CaCO₃) | 198 |
| Degrees Clark (°Clark) | 13.9 |
| Degrees French (°fH) | 19.8 |
| Degrees German (°dH) | 11.1 |
| Calcium (mg/L Ca²⁺) | 79 |
Supplier and area
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Common questions about DE65
What is the water hardness in DE65 Derby?
Which water company supplies DE65?
Is the water in DE65 safe to drink?
How can I reduce water hardness in DE65?
What does 198 ppm water hardness mean?
What size water softener do I need in DE65?
How much does it cost to run a water softener in DE65?
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