Water hardness in Yeosu
33 mg/L soft
Tap water in Yeosu is soft: 33 mg/L (1.9 gpg · 1.8 °dH · 3.3 °fH).
Source: K-water / 전남광주통합특별시 여수시 via data.go.kr (2025) · data checked 2026-10-21
Range across supply zones: 23–39 mg/L.
Statutory tests of treated water in Yeosu give 32.5 mg/L CaCO₃ as the 2025 median, with plants ranging from 22.5 to 39.0 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. Limescale is a minor issue at this level, mostly a thin film on kettles and shower glass.
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 | 33 mg/L |
|---|---|
| Utility | Yeosu-si (전남광주통합특별시 여수시) |
How Yeosu compares
- Tap water in Yeosu is 43 % softer than the median of the 127 cities we track in South Korea (57 mg/L).
- By hardness it ranks 105 of 127 in South Korea (1 = hardest); 17 % of these cities have softer water.
- In Jeollanam-do it is number 11 of 19 cities; the regional median is 35 mg/L.
- Nearest city with clearly softer water: Goheung, 36 km away (21 mg/L).
- Nearest city with clearly harder water: Gwangyang, 20 km away (41 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 Yeosu
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 2 °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 Yeosu water hard or soft?
It is soft: 33 mg/L as CaCO₃ (1.9 gpg, 1.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Yeosu 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 Yeosu water?
1.9 gpg, equal to 1.8 °dH, 3.3 °fH or 33 mg/L calcium carbonate.
What dishwasher salt setting should I use in Yeosu?
For 33 mg/L (1.8 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Yeosu?
No. With soft water a softener adds nothing.
Source
Source: K-water / 전남광주통합특별시 여수시 via data.go.kr (2025). Method: figure published by the water supplier. K-water / 전남광주통합특별시 여수시 via data.go.kr · Outdated figure? Tell us