Tap Water in CT6
Herne — South East Water
Tap water in Herne, supplied by South East Water, has the character of a chalk aquifer source, typical of southern and eastern England. It's moderately soft, in the lower end of the national range, with a total hardness of 108 mg/L as CaCO₃. Bicarbonate is high at 401 mg/L: this water suits dark-roasted, milk-based coffee well, but will strip the acidity from lighter roasts and pour-over brewing.
Mineral composition
| mg/L | |
|---|---|
| Calcium | 109 |
| Magnesium | 6 |
| Sodium | 16 |
| Sulfate | 22 |
| Chloride | 29 |
| Bicarbonate | 401 |
Additional info
| Hardness | 108.05 as CaCO₃ |
| Alkalinity | 328.25 as CaCO₃ |
| pH | 7.35 |
| Conductivity | 580.85 µS/cm |
| Source | South East Water |
| Data year | 2025 |
What this means
Kettle & appliances
Some light mineral residue may appear in kettles over time, but significant limescale buildup is unlikely. No treatment needed for most appliances.
Espresso
A good range for espresso. Enough mineral content to provide body and balance acidity without posing a real scale risk to the machine. Most specialty coffee water targets fall in or near this band.
Filter & pour-over
Excellent for filter brewing. The slight mineral content adds body and sweetness without masking acidity, giving a balanced cup across most roast levels. This is close to the SCA's recommended range for brewed coffee.
Drinking & cooking
Tastes clean with a slight mineral presence. Good all-round water for cooking; it won't interfere with delicate flavours or leave noticeable deposits.
Bicarbonate
Extremely high buffering that makes this water difficult to work with for any brewing or coffee application without significant dilution or acid treatment: mash pH will sit stubbornly high, extraction will be unbalanced, and espresso will taste flat and chalky with no discernible acidity.
Closest water profiles
Nearby areas
CT3
Your water is pumped from underground sources in the chalk at Wingham.
Southern Water
CT4
Your water is pumped from underground sources in the chalk at Wingham.
Southern Water
CT7
Your water is pumped from underground sources in the chalk at Wingham.
Southern Water
CT8
Your water is pumped from underground sources in the chalk at Martin Mill and Ma
Southern Water
CT9
Your water is pumped from underground sources in the chalk at Martin Mill and Ma
Southern Water
CT10
Your water is pumped from underground sources in the chalk at Lord of the Manor,
Southern Water
Data sourced from South East Water (2025). Looking for a specific address? Look up your full postcode for the most accurate result.