Water hardness

PL8 Plymouth

Near or below the UK average. Limescale builds slowly.

At 137 ppm, Plymouth ranks near the UK's softest water areas — compare it against the hardest areas.

Moderately Hard 137 ppm South West South West Water
Your reading
137
parts per million
Soft
Moderate
Hard
Very hard
0100200300400+

What this means for your home

Based on 137 ppm in Plymouth (moderately hard water).

  • Noticeable limescale buildup in kettles and boilers
  • Soap may not lather as easily
  • Showerhead may need descaling periodically
  • Slight film on glassware after washing
Heat loss
4%
Light scaling
Softener salt
£8–13
per year
Worth it?
No
at 137 ppm
Suggested for moderately 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 Plymouth?

A verdict and running-cost estimate based on PL8's 137 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 19.6 days
Salt running cost
£8–13
per year (~28 kg salt)
Limescale
4%
est. heater efficiency loss. Light scaling
Soap saving
Low
Some saving: expect to use slightly less soap and detergent.

Appliance impact at 137 ppm: slight: minor descaling extends kettle/boiler life. Sized for a 4-person home; regenerates roughly every 20 days (estimate). Figures are conservative estimates and vary with household size and usage.

Water quality details

Hardness data for PL8

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

Hardness measurements

Parts per million (ppm CaCO₃)137
Degrees Clark (°Clark)9.6
Degrees French (°fH)13.7
Degrees German (°dH)7.7
Calcium (mg/L Ca²⁺)55

Supplier and area

Water supplier South West Water
Region South West
County Devon
Hardness band Moderately Hard
UK average 207 ppm
Visit South West Water page
Official source
South West Water water-hardness report

Most of the region is soft water, except East Devon; use the postcode lookup on this page to find your address's specific water quality.

Nearby

Other areas near Plymouth

PL7
Plymouth
136ppm
Moderately Hard
PL9
Plymouth
138ppm
Moderately Hard
PL10
Torpoint
44ppm
Soft
FAQ

Common questions about PL8

What is the water hardness in PL8 Plymouth?
The water in PL8 Plymouth has a hardness level of 137 ppm (parts per million) calcium carbonate, classified as moderately hard. This is 70 ppm below the UK national average of 207 ppm.
Which water company supplies PL8?
PL8 Plymouth is supplied by South West Water. South West Water serves the South West region.
Is the water in PL8 safe to drink?
Yes. Moderately Hard water at 137 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 PL8?
At 137 ppm, the water in PL8 is moderately hard and unlikely to cause significant issues. A jug filter can improve taste, but a water softener is generally not necessary.
What does 137 ppm water hardness mean?
137 ppm means there are 137 parts per million of calcium carbonate dissolved in the water. This is equivalent to 9.6 Clark degrees, 7.7 German degrees, or 13.7 French degrees. Water above 180 ppm is generally considered hard.
What size water softener do I need in PL8?
For a typical 4-person home at 137 ppm, a 24,000 grain softener is a sensible size. It would regenerate roughly every 19.6 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 PL8?
At 137 ppm, expect to use about 28 kg of salt a year, costing roughly £8–£13/year. Water is soft to moderate, so limescale and soap costs are low and a softener rarely pays back.

Your Plymouth water action plan

Enter your email for the short list of things worth doing at 137 ppm, and the upgrades you can safely ignore.

Check another postcode

Compare hardness across areas before moving or buying a softener.