Water hardness in Gwangju (Gwangju)
26 mg/L soft
Tap water in Gwangju (Gwangju) is soft: 26 mg/L (1.5 gpg · 1.5 °dH · 2.6 °fH).
Source: K-water / 전남광주통합특별시 광주광역시 via data.go.kr (2025) · data checked 2026-10-20
Range across supply zones: 25–27 mg/L.
Gwangju reports a median of 26.0 mg/L CaCO₃ for its treated water in 2025, with plants ranging from 25.0 to 27.0 mg/L. Water in this region comes mainly from the Yeongsan and Seomjin basins and their dams, such as Juam; this utility's own source is not confirmed here. At this level scale builds up slowly, so kettles and heating elements stay fairly clean and a softener is rarely needed.
Korean waterworks report hardness (경도) in mg/L CaCO₃; the drinking-water standard is 300 mg/L (1,000 mg/L for some sources).
Water data
| Total hardness | 26 mg/L |
|---|---|
| Utility | Gwangju (전남광주통합특별시 광주광역시) |
How Gwangju (Gwangju) compares
- Tap water in Gwangju (Gwangju) is 54 % softer than the median of the 127 cities we track in South Korea (57 mg/L).
- By hardness it ranks 116 of 127 in South Korea (1 = hardest); 9 % of these cities have softer water.
- Nearest city with clearly softer water: Wando, 95 km away (16 mg/L).
- Nearest city with clearly harder water: Hwasun, 12 km away (52 mg/L).
Ranking of the hardest and softest water in South Korea →
What it means at home
- Little or no limescale in kettles, water heaters or washing machines.
- Soap lathers easily; water does not dry skin or hair.
- Dishwasher: salt setting at minimum or off.
- No softener needed; a jug filter only changes taste.
How much salt will you use for softening?
No. Water this soft does not need softening.
Descale a coffee machine or kettle about every 6 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Gwangju
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 1 °dH |
| AEG / Electrolux | 1 |
| Beko | 1st |
| Hoover | S0 |
| LG | H0 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Gwangju (Gwangju) water hard or soft?
It is soft: 26 mg/L as CaCO₃ (1.5 gpg, 1.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Gwangju (Gwangju) safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Korean waterworks report hardness (경도) in mg/L CaCO₃; the drinking-water standard is 300 mg/L (1,000 mg/L for some sources).
How many grains per gallon is Gwangju (Gwangju) water?
1.5 gpg, equal to 1.5 °dH, 2.6 °fH or 26 mg/L calcium carbonate.
What dishwasher salt setting should I use in Gwangju (Gwangju)?
For 26 mg/L (1.5 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Gwangju (Gwangju)?
No. With soft water a softener adds nothing.
Source
Source: K-water / 전남광주통합특별시 광주광역시 via data.go.kr (2025). Method: figure published by the water supplier. K-water / 전남광주통합특별시 광주광역시 via data.go.kr · Outdated figure? Tell us