Average 86 ppm across 82 postcodes and 3 towns.
The average water hardness in Devon is 86 ppm, classified as slightly hard. Across 82 postcode districts in the South West region, hardness ranges from 28 ppm to 138 ppm.
Devon is served by South West Water. With slightly hard water, limescale is unlikely to be a major concern in most homes.
Sorted by hardness — tap a town for full details.
Companies supplying water to this county.
Every postcode district in the county, sorted by hardness.
Learn more about water hardness and how to manage it.
Be notified when water companies in Devon report changes to hardness levels.