WaterWater Hardness in Hertfordshire
South East • 53 postcode districts • 3 towns
Water Hardness Across Hertfordshire
The average water hardness in Hertfordshire is 303 ppm, classified as very hard. Across 53 postcode districts in the South East region, hardness ranges from 239 ppm to 378 ppm.
Hertfordshire is served by Affinity Water and Anglian Water and Thames Water. With very hard water, residents may benefit from a <a href="/water-softener-guide/">water softener</a> to reduce limescale and protect appliances.
Towns in Hertfordshire
| Town | Avg Hardness | PPM | Level |
|---|---|---|---|
| Stevenage | 352 ppm | Very Hard | |
| Hemel Hempstead | 288 ppm | Hard | |
| St Albans | 244 ppm | Hard |
Water Companies in Hertfordshire
All Postcodes in Hertfordshire
| Postcode | Town | Hardness | PPM | Level |
|---|---|---|---|---|
| SG9 | Buntingford | 378 ppm | Very Hard | |
| SG8 | Royston | 377 ppm | Very Hard | |
| SG7 | Baldock | 376 ppm | Very Hard | |
| SG6 | Letchworth Garden City | 375 ppm | Very Hard | |
| SG5 | Hitchin | 374 ppm | Very Hard | |
| SG4 | Hitchin | 373 ppm | Very Hard | |
| SG3 | Knebworth | 372 ppm | Very Hard | |
| SG2 | Stevenage | 371 ppm | Very Hard | |
| SG1 | Stevenage | 370 ppm | Very Hard | |
| SG19 | Sandy | 337 ppm | Very Hard | |
| SG18 | Biggleswade | 336 ppm | Very Hard | |
| SG17 | Shefford | 335 ppm | Very Hard | |
| SG16 | Henlow | 334 ppm | Very Hard | |
| SG15 | Arlesey | 333 ppm | Very Hard | |
| SG14 | Hertford | 332 ppm | Very Hard | |
| SG13 | Hertford | 331 ppm | Very Hard | |
| SG12 | Ware | 330 ppm | Very Hard | |
| SG11 | Ware | 329 ppm | Very Hard | |
| SG10 | Much Hadham | 328 ppm | Very Hard | |
| HP9 | Beaconsfield | 326 ppm | Very Hard | |
| HP8 | Chalfont St Giles | 325 ppm | Very Hard | |
| HP7 | Amersham | 324 ppm | Very Hard | |
| HP6 | Amersham | 323 ppm | Very Hard | |
| HP5 | Chesham | 322 ppm | Very Hard | |
| HP4 | Berkhamsted | 321 ppm | Very Hard | |
| HP3 | Hemel Hempstead | 320 ppm | Very Hard | |
| HP2 | Hemel Hempstead | 319 ppm | Very Hard | |
| HP1 | Hemel Hempstead | 318 ppm | Very Hard | |
| HP27 | Princes Risborough | 292 ppm | Hard | |
| HP23 | Tring | 288 ppm | Hard | |
| HP22 | Aylesbury | 287 ppm | Hard | |
| HP21 | Aylesbury | 286 ppm | Hard | |
| HP20 | Aylesbury | 285 ppm | Hard | |
| HP19 | Aylesbury | 261 ppm | Hard | |
| HP18 | Aylesbury | 260 ppm | Hard | |
| HP17 | Aylesbury | 259 ppm | Hard | |
| HP16 | Great Missenden | 258 ppm | Hard | |
| HP15 | High Wycombe | 257 ppm | Hard | |
| HP14 | High Wycombe | 256 ppm | Hard | |
| HP13 | High Wycombe | 255 ppm | Hard | |
| AL10 | Hatfield | 254 ppm | Hard | |
| HP12 | High Wycombe | 254 ppm | Hard | |
| HP11 | High Wycombe | 253 ppm | Hard | |
| HP10 | High Wycombe | 252 ppm | Hard | |
| AL9 | Hatfield | 247 ppm | Hard | |
| AL8 | Welwyn Garden City | 246 ppm | Hard | |
| AL7 | Welwyn Garden City | 245 ppm | Hard | |
| AL6 | Welwyn | 244 ppm | Hard | |
| AL5 | Harpenden | 243 ppm | Hard | |
| AL4 | St Albans | 242 ppm | Hard | |
| AL3 | St Albans | 241 ppm | Hard | |
| AL2 | St Albans | 240 ppm | Hard | |
| AL1 | St Albans | 239 ppm | Hard |
Recommended Products for Hertfordshire
Top picks for households in very hard water areas across Hertfordshire.
Water2Buy W2B200 Water Softener
From ~£400Best-value whole-house ion-exchange softener for UK homes. Eliminates limescale from pipes, boilers, and appliances. Digital metered regeneration — low salt use. 7-year warranty.
View on AmazonPhilips AWP1775 Shower Filter
From ~£30Instant improvement for skin and hair. Reduces chlorine and limescale at the showerhead — no plumbing needed. A good first step before committing to a full softener.
View on AmazonHard Water Guides
Learn more about water hardness and how to manage it.
All counties in South East • Hardest water areas • Softest water areas • Hard water solutions
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