Is Plymouth Water Hard or Soft? Slightly Hard at 91 ppm

The average water hardness in Plymouth is 91 ppm, classified as slightly hard. Plymouth is served by South West Water, covering 35 postcode districts across Devon in the South West region.

Hardness varies across the area. See the table below for a breakdown by postcode district. PL9 has the hardest water at 138 ppm, while PL10 is the softest at 44 ppm.

By postcode

Water Hardness by Postcode in Plymouth

Sorted by hardness. Tap a postcode for full details.

Postcode	Water Company	Hardness	PPM	Level
PL9	South West Water	138	138 ppm	Moderately Hard
PL8	South West Water	137	137 ppm	Moderately Hard
PL7	South West Water	136	136 ppm	Moderately Hard
PL6	South West Water	135	135 ppm	Moderately Hard
PL5	South West Water	134	134 ppm	Moderately Hard
PL4	South West Water	133	133 ppm	Moderately Hard
PL3	South West Water	132	132 ppm	Moderately Hard
PL2	South West Water	131	131 ppm	Moderately Hard
PL1	South West Water	130	130 ppm	Moderately Hard
PL35	South West Water	115	115 ppm	Slightly Hard
PL34	South West Water	114	114 ppm	Slightly Hard
PL33	South West Water	113	113 ppm	Slightly Hard
PL32	South West Water	112	112 ppm	Slightly Hard
PL31	South West Water	111	111 ppm	Slightly Hard
PL30	South West Water	110	110 ppm	Slightly Hard
PL29	South West Water	86	86 ppm	Slightly Hard
PL28	South West Water	85	85 ppm	Slightly Hard
PL27	South West Water	84	84 ppm	Slightly Hard
PL26	South West Water	83	83 ppm	Slightly Hard
PL25	South West Water	82	82 ppm	Slightly Hard
PL24	South West Water	81	81 ppm	Slightly Hard
PL23	South West Water	80	80 ppm	Slightly Hard
PL22	South West Water	79	79 ppm	Slightly Hard
PL21	South West Water	78	78 ppm	Slightly Hard
PL20	South West Water	77	77 ppm	Slightly Hard
PL19	South West Water	53	53 ppm	Soft
PL18	South West Water	52	52 ppm	Soft
PL17	South West Water	51	51 ppm	Soft
PL16	South West Water	50	50 ppm	Soft
PL15	South West Water	49	49 ppm	Soft
PL14	South West Water	48	48 ppm	Soft
PL13	South West Water	47	47 ppm	Soft
PL12	South West Water	46	46 ppm	Soft
PL11	South West Water	45	45 ppm	Soft
PL10	South West Water	44	44 ppm	Soft

Suppliers

Water Companies Serving Plymouth

Tap for full coverage area and hardness data.

South West Water

80 ppm Slightly Hard

Each water company publishes its own hardness data, so you can cross-check the Plymouth figures here against the published hardness data from South West Water.

Test Your Water in Plymouth

At 91 ppm, your water is slightly hard. A home testing kit lets you verify the exact hardness and check for other contaminants.

TESPERT 16-in-1 Water Testing Kit

Home water test strips that check hardness, pH, chlorine, lead, and 12 other parameters. Results in around 60 seconds. 125 strips per pack.

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FAQ

Common questions about Plymouth water

Is Plymouth water hard or soft?

Plymouth is classified as slightly hard, averaging 91 ppm across 35 postcode districts. Limescale build-up is minimal at this level, though individual postcodes vary.

Which postcode in Plymouth has the hardest water?

PL9 has the hardest water in Plymouth at 138 ppm, while PL10 is the softest at 44 ppm. See the full table above for every district.

Which water company supplies Plymouth?

Plymouth is supplied by South West Water, covering 35 postcode districts across Devon.

Is tap water in Plymouth safe to drink?

Hardness is not a safety issue: the World Health Organization sets no health-based limit for water hardness, so hard and soft water are both fine to drink. Drinking water quality is regulated by the Drinking Water Inspectorate in England and Wales and the Drinking Water Quality Regulator in Scotland, and your water company publishes test results for your area.

Does Plymouth have any harder-water postcodes?

PL9 is the hardest district at 138 ppm (moderately hard), though most of Plymouth averages 91 ppm.