Arlington, WA water hardness

Tap water hardness
29mg/L
1.7gpg
SoftCounty estimate

County estimate from 33,817 water samples in Snohomish County · July 2026

WA typical
36 mg/L
EPA health violations since 2016
0
Data
County estimate

Water samples from around Arlington put hardness at about 29 mg/L (1.7 gpg), which would be soft on the USGS scale. Treat this as a rough guide: it is the median of 33,817 samples taken across Snohomish County, mostly wells and streams, not a test of Arlington's treated tap water. One more reason for caution: EPA lists Arlington's water system as using surface water, which is often softer than the wells behind the county figure.

Arlington on the hardness scale, with nearby cities
060120180240300360+WA typical 36Mukilteo: 13 mg/LMukilteo 13Lake Stickney: 13 mg/LLake Stickney 13Mill Creek: 13 mg/LMill Creek 13Mount Vernon: 18 mg/LMount Vernon 18Everett: 19 mg/LEverett 19Eastmont: 22 mg/LEastmont 22Marysville: 29 mg/LMarysville 29Lake Stevens: 36 mg/LLake Stevens 36Snohomish: 36 mg/LSnohomish 36Silver Firs: 43 mg/LSilver Firs 43Arlington 29mg/L as calcium carbonate060120180240300360+WA 36Mount Vernon: 18 mg/LMount Vern. 18Everett: 19 mg/LEverett 19Eastmont: 22 mg/LEastmont 22Marysville: 29 mg/LMarysville 29Lake Stevens: 36 mg/LLake Steve. 36Snohomish: 36 mg/LSnohomish 3629 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Arlington sits close to the typical Washington figure of 36 mg/L. Of the 10 nearest cities we track, 6 have softer water and 3 have harder. The range nearby runs from 13 mg/L in Mukilteo to 43 in Silver Firs.

What 29 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 29 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 Arlington's water system

Arlington City of · PWSID WA5302950

No health-based violations since 2016

Serves about 29,508 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

EPA lists this system as serving Arlington.

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 Arlington water hard?

No. It measures about 29 mg/L (1.7 grains per gallon), which the USGS classes as soft.

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

About 1.7 gpg. One grain per gallon equals 17.1 mg/L, so 29 mg/L divided by 17.1 gives 1.7.

Has the Arlington water system had EPA violations?

EPA records show no health-based violations for Arlington City of since 2016.

Nearby cities

All 145 cities in Washington

Hardness data: TapWaterData US Water Hardness (county estimate, July 4, 2026), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.