Water hardness

DL1 Darlington

Near or below the UK average. Limescale builds slowly.

At 74 ppm, Darlington ranks near the UK's softest water areas — compare it against the hardest areas.

Slightly Hard 74 ppm North East Northumbrian Water
Your reading
74
parts per million
Soft
Moderate
Hard
Very hard
0100200300400+

What this means for your home

Based on 74 ppm in Darlington (slightly hard water).

  • Minor limescale may appear in kettles over time
  • Soap lathers reasonably well
  • Appliances generally unaffected
  • Good balance of mineral taste
Heat loss
1%
Minimal scaling
Softener salt
£4–7
per year
Worth it?
No
at 74 ppm
Suggested for slightly hard water
Filter jug (optional)
Mainly a taste preference, limescale won't be a real issue here.
From £20
Maintenance habits
Routine descaling once or twice a year is plenty.
Free
Softening

Should you soften the water in Darlington?

A verdict and running-cost estimate based on DL1's 74 ppm reading, for a typical 4-person household.

Softener optional

Water is soft to moderate, so limescale and soap costs are low and a softener rarely pays back.

Recommended size
24k
grain capacity, regenerates ~every 36.2 days
Salt running cost
£4–7
per year (~15 kg salt)
Limescale
1%
est. heater efficiency loss. Minimal scaling
Soap saving
Minimal
Water is already soft, so there is little detergent saving from softening.

Appliance impact at 74 ppm: negligible: appliances reach full expected life. Sized for a 4-person home; regenerates roughly every 36 days (estimate). Figures are conservative estimates and vary with household size and usage.

Water quality details

Hardness data for DL1

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

Hardness measurements

Parts per million (ppm CaCO₃)74
Degrees Clark (°Clark)5.2
Degrees French (°fH)7.4
Degrees German (°dH)4.1
Calcium (mg/L Ca²⁺)30

Supplier and area

Water supplier Northumbrian Water
Region North East
County County Durham
Hardness band Slightly Hard
UK average 207 ppm
Visit Northumbrian Water page
Official source
Northumbrian Water water-hardness report

This page explains local hardness and links to a postcode water quality checker so you can find your supply zone's level.

Nearby

Other areas near Darlington

DL2
Darlington
75ppm
Slightly Hard
DL3
Darlington
76ppm
Slightly Hard
FAQ

Common questions about DL1

What is the water hardness in DL1 Darlington?
The water in DL1 Darlington has a hardness level of 74 ppm (parts per million) calcium carbonate, classified as slightly hard. This is 133 ppm below the UK national average of 207 ppm.
Which water company supplies DL1?
DL1 Darlington is supplied by Northumbrian Water. Northumbrian Water serves the North East region.
Is the water in DL1 safe to drink?
Yes. Slightly Hard water at 74 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 DL1?
At 74 ppm, the water in DL1 is slightly hard and unlikely to cause significant issues. A jug filter can improve taste, but a water softener is generally not necessary.
What does 74 ppm water hardness mean?
74 ppm means there are 74 parts per million of calcium carbonate dissolved in the water. This is equivalent to 5.2 Clark degrees, 4.1 German degrees, or 7.4 French degrees. Water above 180 ppm is generally considered hard.
What size water softener do I need in DL1?
For a typical 4-person home at 74 ppm, a 24,000 grain softener is a sensible size. It would regenerate roughly every 36.2 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 DL1?
At 74 ppm, expect to use about 15 kg of salt a year, costing roughly £4–£7/year. Water is soft to moderate, so limescale and soap costs are low and a softener rarely pays back.

Your Darlington water action plan

Enter your email for the short list of things worth doing at 74 ppm, and the upgrades you can safely ignore.

Check another postcode

Compare hardness across areas before moving or buying a softener.