NN1 Northampton
Harder than the UK average. Expect visible limescale on kettles and taps.
At 290 ppm, Northampton sits among the UK's hardest water areas — compare it against the softest areas.
What this means for your home
Based on 290 ppm in Northampton (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 Northampton?
A verdict and running-cost estimate based on NN1's 290 ppm reading, for a typical 4-person household.
Water is hard to very hard, so appliance, scale and soap savings typically pay back a softener within a few years.
Appliance impact at 290 ppm: noticeable: boiler/dishwasher life cut without descaling. Sized for a 4-person home; regenerates roughly every 9 days (estimate). Figures are conservative estimates and vary with household size and usage.
Hardness data for NN1
Sourced from Anglian Water's published water-quality reports and public records.
Hardness measurements
| Parts per million (ppm CaCO₃) | 290 |
| Degrees Clark (°Clark) | 20.3 |
| Degrees French (°fH) | 29 |
| Degrees German (°dH) | 16.2 |
| Calcium (mg/L Ca²⁺) | 116 |
Supplier and area
Read the hard water explainer then use the linked postcode checker to confirm if you are in a hard water area; the region averages very hard.
Other areas near Northampton
Common questions about NN1
What is the water hardness in NN1 Northampton?
Which water company supplies NN1?
Is the water in NN1 safe to drink?
How can I reduce water hardness in NN1?
What does 290 ppm water hardness mean?
What size water softener do I need in NN1?
How much does it cost to run a water softener in NN1?
Fix hard water in Northampton
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