Auburn, CA water hardness

Tap water hardness
11mg/L
0.6gpg
Soft

Reported by Placer Cwa - Auburn/Bowman · July 2025

CA typical
121 mg/L
EPA health violations since 2016
0
Data
Utility report

Tap water in Auburn has about 11 mg/L of hardness, which is 0.6 grains per gallon. On the USGS scale that counts as soft. The number comes from Placer Cwa - Auburn/Bowman, dated July 2025.

Auburn on the hardness scale, with nearby cities
060120180240300360+CA typical 121Loomis: 11 mg/LLoomis 11Rocklin: 11 mg/LRocklin 11North Auburn: 12 mg/LNorth Auburn 12Granite Bay: 13 mg/LGranite Bay 13El Dorado Hills: 14 mg/LEl Dorado Hills 14Cameron Park: 14 mg/LCameron Park 14Lincoln: 15 mg/LLincoln 15Alta Sierra: 16 mg/LAlta Sierra 16Folsom: 18 mg/LFolsom 18Roseville: 19 mg/LRoseville 19Auburn 11mg/L as calcium carbonate060120180240300360+CA 121Loomis: 11 mg/LLoomis 11Rocklin: 11 mg/LRocklin 11North Auburn: 12 mg/LNorth Aubu. 12Granite Bay: 13 mg/LGranite Bay 13El Dorado Hills: 14 mg/LEl Dorado. 14Lincoln: 15 mg/LLincoln 1511 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 11 mg/L, Auburn is 110 mg/L below the typical California figure of 121. None of the 10 nearest cities we track has softer water. The range nearby runs from 11 mg/L in Loomis to 19 in Roseville.

What 11 mg/L means at home

Soap and shampoo lather with very little product. Kettles and showerheads stay mostly free of white crust.

Some people notice that soap feels slow to rinse off in soft water. That slippery feel is normal and harmless.

Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.

What to do about it

Nothing, as far as hardness goes. At 11 mg/L a softener would have almost nothing to remove.

Carbon filter

If the water tastes of chlorine, a pitcher or faucet carbon filter takes care of that. It does not change hardness.

EPA record for Auburn's water system

Placer Cwa - Auburn/Bowman · PWSID CA3110005

No health-based violations since 2016

Serves about 27,317 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.

Questions

Is Auburn water hard?

No. It measures about 11 mg/L (0.6 grains per gallon), which the USGS classes as soft.

What is the water hardness in Auburn in grains per gallon?

About 0.6 gpg. One grain per gallon equals 17.1 mg/L, so 11 mg/L divided by 17.1 gives 0.6.

Has the Auburn water system had EPA violations?

EPA records show no health-based violations for Placer Cwa - Auburn/Bowman since 2016.

Nearby cities

All 515 cities in California

Hardness data: TapWaterData US Water Hardness (utility report, July 23, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.