Water hardness in Glendale (California)
21 gpg very hard
Tap water in Glendale (California) is very hard: 21 gpg (360 mg/L · 20.2 °dH · 36 °fH).
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA1910043 (2025-04) · data checked 2026-10-19
Range across supply zones: 350–370 mg/L.
The Glendale figure comes from State Water Resources Control Board lab results for the Glendale water system. The median of 17 finished-water results from 2021 to 2025 is 360 mg/L as CaCO3 (21.0 gpg), in a narrow range of 350 to 370 mg/L. The samples are listed at treatment-plant points. This is among the hardest water in our US set, and a softener is worth serious consideration.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 21 gpg |
|---|---|
| Utility | Glendale-City, Water Dept. |
How Glendale (California) compares
- Tap water in Glendale (California) is 132 % harder than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 108 of 1372 in the United States (1 = hardest); 92 % of these cities have softer water.
- In California it is number 23 of 336 cities; the regional median is 9.5 gpg.
- Nearest city with clearly softer water: Pasadena, 10 km away (10 gpg).
- Nearest city with clearly harder water: Redondo Beach, 40 km away (29.3 gpg).
Ranking of the hardest and softest water in the United States →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Glendale
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 20 °dH |
| AEG / Electrolux | 5 |
| Beko | 6th |
| Hoover | S3 |
| LG | H3 |
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 Glendale (California) water hard or soft?
It is very hard: 360 mg/L as CaCO₃ (21 gpg, 20.2 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Glendale (California) 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 Glendale (California) water?
21 gpg, equal to 20.2 °dH, 36 °fH or 360 mg/L calcium carbonate.
What dishwasher salt setting should I use in Glendale (California)?
For 360 mg/L (20.2 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Glendale (California)?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA1910043 (2025-04). Method: own measurement. California SWRCB Division of Drinking Water, EDT lab results, system CA1910043 · Outdated figure? Tell us