Water Hardness in Durham

County Durham, North East • 9 postcode districts

Moderately Hard

The average water hardness in Durham is 126 ppm, classified as moderately hard. Durham is served by Northumbrian Water, covering 9 postcode districts across County Durham in the North East region.

Hardness varies across the area — see the table below for a breakdown by postcode district.

Water Hardness by Postcode in Durham

Postcode	Water Company	Hardness	PPM	Level
DH7	Northumbrian Water	150 ppm	150 ppm	Moderately Hard
DH6	Northumbrian Water	149 ppm	149 ppm	Moderately Hard
DH5	Northumbrian Water	148 ppm	148 ppm	Moderately Hard
DH4	Northumbrian Water	147 ppm	147 ppm	Moderately Hard
DH3	Northumbrian Water	146 ppm	146 ppm	Moderately Hard
DH2	Northumbrian Water	145 ppm	145 ppm	Moderately Hard
DH1	Northumbrian Water	144 ppm	144 ppm	Moderately Hard
DH9	Northumbrian Water	51 ppm	51 ppm	Soft
DH8	Northumbrian Water	50 ppm	50 ppm	Soft

Water Companies Serving Durham

Northumbrian Water

Average hardness: 101 ppm (Slightly Hard) • 122 postcodes served

Get Water Hardness Updates

Be notified when your water company reports changes to hardness levels.