North East · County

Water hardness in County Durham

Average 107 ppm across 26 postcodes and 2 towns.

Range 50–150 ppm
Towns 2
Suppliers Northumbrian Water

County average

107

ppm CaCO₃

Slightly Hard

Soft

Moderate

Hard

Very hard

0100200300400+

107

Avg ppm

Min ppm

150

Max ppm

Postcodes

Water Hardness Across County Durham

The average water hardness in County Durham is 107 ppm, classified as slightly hard. Across 26 postcode districts in the North East region, hardness ranges from 50 ppm to 150 ppm.

County Durham is served by Northumbrian Water. With slightly hard water, limescale is unlikely to be a major concern in most homes.

By town

Towns in County Durham

Sorted by hardness — tap a town for full details.

Town	Hardness	PPM	Level
Durham	126	126 ppm	Moderately Hard
Darlington	97	97 ppm	Slightly Hard

Suppliers

Water Companies in County Durham

Companies supplying water to this county.

Northumbrian Water

101 ppm Slightly Hard

All postcodes

Postcodes in County Durham

Every postcode district in the county, sorted by hardness.

Postcode	Town	Hardness	PPM	Level
DH7	Durham	150	150 ppm	Moderately Hard
DH6	Durham	149	149 ppm	Moderately Hard
DH5	Houghton Le Spring	148	148 ppm	Moderately Hard
DH4	Houghton Le Spring	147	147 ppm	Moderately Hard
DH3	Chester Le Street	146	146 ppm	Moderately Hard
DH2	Chester Le Street	145	145 ppm	Moderately Hard
DH1	Durham	144	144 ppm	Moderately Hard
DL17	Ferryhill	122	122 ppm	Moderately Hard
DL16	Spennymoor	121	121 ppm	Moderately Hard
DL15	Crook	120	120 ppm	Slightly Hard
DL14	Bishop Auckland	119	119 ppm	Slightly Hard
DL13	Bishop Auckland	118	118 ppm	Slightly Hard
DL12	Barnard Castle	117	117 ppm	Slightly Hard
DL11	Richmond	116	116 ppm	Slightly Hard
DL10	Richmond	115	115 ppm	Slightly Hard
DL9	Catterick Garrison	82	82 ppm	Slightly Hard
DL8	Bedale	81	81 ppm	Slightly Hard
DL7	Northallerton	80	80 ppm	Slightly Hard
DL6	Northallerton	79	79 ppm	Slightly Hard
DL5	Newton Aycliffe	78	78 ppm	Slightly Hard
DL4	Shildon	77	77 ppm	Slightly Hard
DL3	Darlington	76	76 ppm	Slightly Hard
DL2	Darlington	75	75 ppm	Slightly Hard
DL1	Darlington	74	74 ppm	Slightly Hard
DH9	Stanley	51	51 ppm	Soft
DH8	Consett	50	50 ppm	Soft

Test Your Water in County Durham

At 107 ppm on average, your water is slightly hard. A home testing kit lets you verify the exact hardness for your postcode and check for other contaminants.

TESPERT 16-in-1 Water Testing Kit

From ~£10

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

View on Amazon

Hard Water Guides

Learn more about water hardness and how to manage it.

What Is Water Hardness? Hard Water Effects Solutions

All counties in North East · Hardest water areas · Softest water areas · Hard water solutions

Get County Durham Water Updates

Be notified when water companies in County Durham report changes to hardness levels.

Get a free quote