South West Water water hardness
Ranges from soft to hard across the supply area.
South West Water supplies water ranging from soft to hard across its area, so the figure for your own postcode is worth checking.
Most of the water in our region is sourced from moorland rivers and reservoirs and is classed as soft or moderately soft. If you live in East Devon, your water comes from boreholes drilled deep underground, and this water is classed as slightly or moderately hard.
South West Water, on their own website, source — checked 2026-08-24
Mostly soft granite-moorland water in Devon and Cornwall. The Bournemouth Water area it now owns is hard, so the range is misleading if read as one figure.
What this means for your home
You have soft water — there is no limescale problem to fix.
A water softener would be money spent on a problem you do not have, and anyone trying to sell you one here is worth questioning. If you want to improve your water it will be about taste, chlorine or older pipework, not hardness. Soft water is also slightly more inclined to dissolve metals from old plumbing, which is a different reason to filter drinking water.
Where South West Water supplies
Regions: South West England
Counties and areas: Devon, Cornwall, Dorset, Somerset
Supply boundaries do not follow county boundaries, and several companies may supply parts of the same county. Always check your own postcode.