Water hardness in La Puente
13 gpg very hard
Tap water in La Puente is very hard: 13 gpg (223 mg/L · 12.5 °dH · 22.3 °fH).
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA1910060 (2026-06) · data checked 2026-10-19
Range across supply zones: 216–230 mg/L.
The figure is for La Puente Valley County Water District, which serves only a small part of La Puente. State Water Resources Control Board lab results give a median of 223 mg/L as CaCO3 (13.0 gpg) from 200 finished-water results, 2021 to 2026, with a range of 216 to 230 mg/L. Other suppliers cover the rest of the city. Where it applies, the water is very hard.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 13 gpg |
|---|---|
| Utility | La Puente Valley Cwd |
How La Puente compares
- Tap water in La Puente is 44 % harder than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 452 of 1372 in the United States (1 = hardest); 67 % of these cities have softer water.
- In California it is number 99 of 336 cities; the regional median is 9.5 gpg.
- Nearest city with clearly softer water: West Covina, 4 km away (9.7 gpg).
- Nearest city with clearly harder water: La Habra Heights, 8 km away (17.9 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 La Puente
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 12 °dH |
| AEG / Electrolux | 3 |
| Beko | 3rd |
| Hoover | S2 |
| LG | H2 |
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 La Puente water hard or soft?
It is very hard: 223 mg/L as CaCO₃ (13 gpg, 12.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in La Puente 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 La Puente water?
13 gpg, equal to 12.5 °dH, 22.3 °fH or 223 mg/L calcium carbonate.
What dishwasher salt setting should I use in La Puente?
For 223 mg/L (12.5 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in La Puente?
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 CA1910060 (2026-06). Method: own measurement. California SWRCB Division of Drinking Water, EDT lab results, system CA1910060 · Outdated figure? Tell us