Water hardness

DE23 Derby

Harder than the UK average. Expect visible limescale on kettles and taps.

At 215 ppm, Derby sits among the UK's hardest water areas — compare it against the softest areas.

Hard 215 ppm East Midlands Severn Trent Water
Your reading
215
parts per million
Soft
Moderate
Hard
Very hard
0100200300400+

What this means for your home

Based on 215 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
Heat loss
8%
Moderate scaling
Softener salt
£12–21
per year
Worth it?
Yes
at 215 ppm
Suggested for hard water
Whole-house water softener
Best long-term protection for boilers and pipes.
From £600 installed
Shower head filter
A simple first step for limescale on tiles and glass.
From £25
Filter jug or under-sink
Improves taste and reduces kettle scale.
From £20
Softening

Should you soften the water in Derby?

A verdict and running-cost estimate based on DE23's 215 ppm reading, for a typical 4-person household.

Softener recommended

Hardness is moderate to hard, so a softener cuts scale and soap use and usually pays back over its lifetime.

Recommended size
24k
grain capacity, regenerates ~every 12.5 days
Salt running cost
£12–21
per year (~44 kg salt)
Limescale
8%
est. heater efficiency loss. Moderate scaling
Soap saving
Moderate
Noticeable saving: soaps lather more easily, cutting detergent use.

Appliance impact at 215 ppm: noticeable: boiler/dishwasher life cut without descaling. Sized for a 4-person home; regenerates roughly every 12 days (estimate). Figures are conservative estimates and vary with household size and usage.

Water quality details

Hardness data for DE23

Sourced from Severn Trent Water's published water-quality reports and public records.

Hardness measurements

Parts per million (ppm CaCO₃)215
Degrees Clark (°Clark)15
Degrees French (°fH)21.5
Degrees German (°dH)12
Calcium (mg/L Ca²⁺)86

Supplier and area

Water supplier Severn Trent Water
Region East Midlands
County Derbyshire
Hardness band Hard
UK average 207 ppm
Visit Severn Trent Water page
Official source
Severn Trent Water water-hardness report

Enter your postcode and pick a timeframe to see your area's measured water quality including hardness, with a downloadable PDF report.

Nearby

Other areas near Derby

DE22
Derby
214ppm
Hard
DE24
Derby
216ppm
Hard
FAQ

Common questions about DE23

What is the water hardness in DE23 Derby?
The water in DE23 Derby has a hardness level of 215 ppm (parts per million) calcium carbonate, classified as hard. This is 8 ppm above the UK national average of 207 ppm.
Which water company supplies DE23?
DE23 Derby is supplied by Severn Trent Water. Severn Trent Water serves the East Midlands region.
Is the water in DE23 safe to drink?
Yes. Hard water at 215 ppm is safe to drink. Water hardness affects taste and can cause limescale, but it is not a health risk. In fact, hard water contains beneficial minerals like calcium and magnesium.
How can I reduce water hardness in DE23?
For hard water at 215 ppm, a whole-house water softener is the most effective solution. You can also use a jug filter for drinking water, descaling products for appliances, and a shower filter for better skin and hair.
What does 215 ppm water hardness mean?
215 ppm means there are 215 parts per million of calcium carbonate dissolved in the water. This is equivalent to 15 Clark degrees, 12 German degrees, or 21.5 French degrees. Water above 180 ppm is generally considered hard.
What size water softener do I need in DE23?
For a typical 4-person home at 215 ppm, a 24,000 grain softener is a sensible size. It would regenerate roughly every 12.5 days. Larger households or higher daily use need a bigger unit. These figures are conservative estimates.
How much does it cost to run a water softener in DE23?
At 215 ppm, expect to use about 44 kg of salt a year, costing roughly £12–£21/year. Hardness is moderate to hard, so a softener cuts scale and soap use and usually pays back over its lifetime.

Fix hard water in Derby

Enter your email and we will send the limescale fixes that actually work at 215 ppm, plus what to skip.

Check another postcode

Compare hardness across areas before moving or buying a softener.