Water hardness in Summerville
1.3 gpg soft
Tap water in Summerville is soft: 1.3 gpg (23 mg/L · 1.3 °dH · 2.3 °fH).
Source: Summerville CPW Water Quality Report, reporting year 2025 (2025 data) (2025) · data checked 2026-10-20
Summerville Commissioners of Public Works reports 23 mg/L (1.3 gpg) in its 2025 water quality report, and says the water comes from the Santee Cooper Regional Water System. The figure is a single 2025 sample, so treat it as a snapshot rather than a yearly average. This is very soft water: scale is unlikely, and a softener would add little.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 1.3 gpg |
|---|---|
| Utility | Summerville Commissioners of Public Works (CPW) |
How Summerville compares
- Tap water in Summerville is 85 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 1312 of 1372 in the United States (1 = hardest); 4 % of these cities have softer water.
- In South Carolina it is number 7 of 8 cities; the regional median is 2.6 gpg.
- Nearest city with clearly harder water: North Charleston, 26 km away (3.4 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 Summerville
| 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 Summerville water hard or soft?
It is soft: 23 mg/L as CaCO₃ (1.3 gpg, 1.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Summerville 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 Summerville water?
1.3 gpg, equal to 1.3 °dH, 2.3 °fH or 23 mg/L calcium carbonate.
What dishwasher salt setting should I use in Summerville?
For 23 mg/L (1.3 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Summerville?
No. With soft water a softener adds nothing.
Source
Source: Summerville CPW Water Quality Report, reporting year 2025 (2025 data) (2025). Method: figure published by the water supplier. Summerville CPW Water Quality Report, reporting year 2025 (2025 data) · Outdated figure? Tell us