Water hardness in Sonora
1.3 gpg soft
Tap water in Sonora is soft: 1.3 gpg (23 mg/L · 1.3 °dH · 2.3 °fH).
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA5510001 (2025-08) · data checked 2026-10-20
Range across supply zones: 15–199 mg/L.
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 | Tud - Sonora/Jamestown Water System |
How Sonora compares
- Tap water in Sonora is 85 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 1317 of 1372 in the United States (1 = hardest); 4 % of these cities have softer water.
- In California it is number 322 of 336 cities; the regional median is 9.5 gpg.
- Nearest city with clearly softer water: Isleton, 109 km away (0.9 gpg).
- Nearest city with clearly harder water: Oakdale, 47 km away (4.6 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 Sonora
| 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 Sonora 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 Sonora 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 Sonora 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 Sonora?
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 Sonora?
No. With soft water a softener adds nothing.
Source
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA5510001 (2025-08). Method: own measurement. California SWRCB Division of Drinking Water, EDT lab results, system CA5510001 · Outdated figure? Tell us