Water Hardness Atlas ZIP / postcode

Water hardness in Glendora

8.2 gpg hard

Tap water in Glendora is hard: 8.2 gpg (140 mg/L · 7.8 °dH · 14 °fH).

<6060–120120–180>180 mg/L

Source: California SWRCB Division of Drinking Water, EDT lab results, system CA1910044 (2026-07) · data checked 2026-10-19

Range across supply zones: 113–360 mg/L.

The Glendora figure comes from State Water Resources Control Board lab results for the city water department. The median of 24 results from 2024 to 2026, taken at 8 well points, is 140 mg/L as CaCO3 (8.2 gpg), but results run from 113 to 360 mg/L. The water is hard on median and varies a lot by well. Ask the city which supply serves your address.

USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.

Water data

Total hardness8.2 gpg
UtilityGlendora-City, Water Dept.

How Glendora compares

Ranking of the hardest and softest water in the United States →

What it means at home

How much salt will you use for softening?

Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.

Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).

Estimates for planning, not a quote. Check your appliance manual for exact settings.

Dishwasher setting in Glendora

BrandSetting for this water
BoschH01
Miele8 °dH
AEG / Electrolux2
Beko3rd
HooverS1
LGH2

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 Glendora water hard or soft?

It is hard: 140 mg/L as CaCO₃ (8.2 gpg, 7.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.

Is tap water in Glendora 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 Glendora water?

8.2 gpg, equal to 7.8 °dH, 14 °fH or 140 mg/L calcium carbonate.

What dishwasher salt setting should I use in Glendora?

For 140 mg/L (7.8 °dH) check your manufacturer's table: level 4–5.

Do I need a water softener in Glendora?

Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.

Source

Source: California SWRCB Division of Drinking Water, EDT lab results, system CA1910044 (2026-07). Method: own measurement. California SWRCB Division of Drinking Water, EDT lab results, system CA1910044 · Outdated figure? Tell us

Nearby cities

San Dimas16.4 gpgAzusa8.2 gpgLa Verne19.3 gpgDuarte8.4 gpgPomona15.5 gpgWest Covina9.7 gpg
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