Water hardness in Charleston (South Carolina)
3.2 gpg soft
Tap water in Charleston (South Carolina) is soft: 3.2 gpg (54 mg/L · 3 °dH · 5.4 °fH).
Source: Charleston Water System - 2022 Water Quality Report (2022) · data checked 2026-10-23
This figure is over 3 years old; hardness may have changed.
Charleston Water System treats surface water from the Bushy Park Reservoir and the Edisto River at its Hanahan plant. Coastal Plain river water is low in minerals, so hardness is only 54 mg/L CaCO₃. Scale is minor and a softener adds little. The figure dates from 2022 and may have changed.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 3.2 gpg |
|---|---|
| Utility | Charleston Water System (CWS) |
How Charleston (South Carolina) compares
- Tap water in Charleston (South Carolina) is 65 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 1204 of 1372 in the United States (1 = hardest); 12 % of these cities have softer water.
- In South Carolina it is number 3 of 8 cities; the regional median is 2.6 gpg.
- Nearest city with clearly softer water: Summerville, 35 km away (1.3 gpg).
Ranking of the hardest and softest water in the United States →
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 Charleston
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 3 °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 Charleston (South Carolina) water hard or soft?
It is soft: 54 mg/L as CaCO₃ (3.2 gpg, 3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Charleston (South Carolina) safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
How many grains per gallon is Charleston (South Carolina) water?
3.2 gpg, equal to 3 °dH, 5.4 °fH or 54 mg/L calcium carbonate.
What dishwasher salt setting should I use in Charleston (South Carolina)?
For 54 mg/L (3 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Charleston (South Carolina)?
No. With soft water a softener adds nothing.
Source
Source: Charleston Water System - 2022 Water Quality Report (2022). Method: figure published by the water supplier. Charleston Water System - 2022 Water Quality Report · Outdated figure? Tell us