Tap water hardness in Chungcheongnam-do
We have published hardness data for 5 cities in Chungcheongnam-do. The median is 75 mg/L; the hardest water is in Cheonan (124 mg/L), the softest in Yesan (51 mg/L).
20 % of these cities have hard or very hard water (over 120 mg/L).
Korean waterworks report hardness (경도) in mg/L CaCO₃; the drinking-water standard is 300 mg/L (1,000 mg/L for some sources).
Cities in Chungcheongnam-do, hardest first
| mg/L | mg/L | ||
|---|---|---|---|
| Cheonan | 124 | 124 | hard |
| Dangjin | 82 | 82 | moderately hard |
| Boryeong | 75 | 75 | moderately hard |
| Gongju | 66 | 66 | moderately hard |
| Yesan | 51 | 51 | soft |