Water Hardness Atlas ZIP / postcode

Water hardness in Pittsburg

7.1 gpg hard

Tap water in Pittsburg is hard: 7.1 gpg (122 mg/L · 6.8 °dH · 12.2 °fH).

<6060–120120–180>180 mg/L

Source: California SWRCB Division of Drinking Water, EDT lab results, system CA0710008 (2025-07) · data checked 2026-10-19

Range across supply zones: 59–161 mg/L.

The Pittsburg figure comes from State Water Resources Control Board lab results for the City of Pittsburg system, using finished-water samples. It rests on 5 results from 2021 to 2025: a median of 122 mg/L as CaCO3 (7.1 gpg), with a range of 59.1 to 160.8 mg/L. That sits at the edge between moderately hard and hard. Scale builds slowly to moderately fast.

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

Water data

Total hardness7.1 gpg
UtilityCity Of Pittsburg

How Pittsburg 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 Pittsburg

BrandSetting for this water
BoschH01
Miele7 °dH
AEG / Electrolux2
Beko2nd
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 Pittsburg water hard or soft?

It is hard: 122 mg/L as CaCO₃ (7.1 gpg, 6.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.

Is tap water in Pittsburg 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 Pittsburg water?

7.1 gpg, equal to 6.8 °dH, 12.2 °fH or 122 mg/L calcium carbonate.

What dishwasher salt setting should I use in Pittsburg?

For 122 mg/L (6.8 °dH) check your manufacturer's table: level 4–5.

Do I need a water softener in Pittsburg?

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 CA0710008 (2025-07). Method: own measurement. California SWRCB Division of Drinking Water, EDT lab results, system CA0710008 · Outdated figure? Tell us

Nearby cities

Antioch4.7 gpgConcord4.3 gpgBrentwood21.8 gpgMartinez5.8 gpgWalnut Creek1.1 gpgBenicia4.9 gpg
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