Water hardness

CO7 Colchester

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

At 279 ppm, Colchester sits among the UK's hardest water areas — compare it against the softest areas.

Hard 279 ppm East Of England Anglian Water
Your reading
279
parts per million
Soft
Moderate
Hard
Very hard
0100200300400+

What this means for your home

Based on 279 ppm in Colchester (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
£16–27
per year
Worth it?
Yes
at 279 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 Colchester?

A verdict and running-cost estimate based on CO7's 279 ppm reading, for a typical 4-person household.

Softener recommended

Water is hard to very hard, so appliance, scale and soap savings typically pay back a softener within a few years.

Recommended size
24k
grain capacity, regenerates ~every 9.6 days
Salt running cost
£16–27
per year (~57 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 279 ppm: noticeable: boiler/dishwasher life cut without descaling. Sized for a 4-person home; regenerates roughly every 10 days (estimate). Figures are conservative estimates and vary with household size and usage.

Water quality details

Hardness data for CO7

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

Hardness measurements

Parts per million (ppm CaCO₃)279
Degrees Clark (°Clark)19.5
Degrees French (°fH)27.9
Degrees German (°dH)15.6
Calcium (mg/L Ca²⁺)112

Supplier and area

Water supplier Anglian Water
Region East Of England
County Essex
Hardness band Hard
UK average 207 ppm
Visit Anglian Water page
Official source
Anglian Water Services Ltd water-hardness report

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.

Nearby

Other areas near Colchester

CO6
Colchester
278ppm
Hard
CO8
Bures
280ppm
Hard
CO9
Halstead
281ppm
Hard
FAQ

Common questions about CO7

What is the water hardness in CO7 Colchester?
The water in CO7 Colchester has a hardness level of 279 ppm (parts per million) calcium carbonate, classified as hard. This is 72 ppm above the UK national average of 207 ppm.
Which water company supplies CO7?
CO7 Colchester is supplied by Anglian Water. Anglian Water serves the East Of England region.
Is the water in CO7 safe to drink?
Yes. Hard water at 279 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 CO7?
For hard water at 279 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 279 ppm water hardness mean?
279 ppm means there are 279 parts per million of calcium carbonate dissolved in the water. This is equivalent to 19.5 Clark degrees, 15.6 German degrees, or 27.9 French degrees. Water above 180 ppm is generally considered hard.
What size water softener do I need in CO7?
For a typical 4-person home at 279 ppm, a 24,000 grain softener is a sensible size. It would regenerate roughly every 9.6 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 CO7?
At 279 ppm, expect to use about 57 kg of salt a year, costing roughly £16–£27/year. Water is hard to very hard, so appliance, scale and soap savings typically pay back a softener within a few years.

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