Forest Grove, OR water hardness

Tap water hardness
42mg/L
2.4gpg
Soft

Reported by Forest Grove, City of · July 2025

OR typical
24 mg/L
EPA health violations since 2016
0
Data
Utility report

The water in Forest Grove carries roughly 42 mg/L of dissolved calcium and magnesium, or 2.4 grains per gallon. That is soft water. The number comes from Forest Grove, City of, dated July 2025.

Forest Grove on the hardness scale, with nearby cities
060120180240300360+OR typical 24Bull Mountain: 22 mg/LBull Mountain 22Rockcreek: 23 mg/LRockcreek 23Aloha: 23 mg/LAloha 23Bethany: 23 mg/LBethany 23Cedar Mill: 23 mg/LCedar Mill 23Hillsboro: 24 mg/LHillsboro 24Oak Hills: 35 mg/LOak Hills 35Marlene Village: 35 mg/LMarlene Village 35Beaverton: 35 mg/LBeaverton 35Cedar Hills: 35 mg/LCedar Hills 35Forest Grove 42mg/L as calcium carbonate060120180240300360+OR 24Rockcreek: 23 mg/LRockcreek 23Aloha: 23 mg/LAloha 23Bethany: 23 mg/LBethany 23Hillsboro: 24 mg/LHillsboro 24Oak Hills: 35 mg/LOak Hills 35Marlene Village: 35 mg/LMarlene Vi. 3542 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 42 mg/L, Forest Grove is 18 mg/L above the typical Oregon figure of 24. None of the 10 nearest cities we track has harder water. The range nearby runs from 22 mg/L in Bull Mountain to 35 in Oak Hills.

What 42 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 42 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 Forest Grove's water system

Forest Grove, City of · PWSID OR4100305

No health-based violations since 2016

Serves about 26,838 people from surface water.

Health-based
0
Monitoring or reporting
26
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 Forest Grove water hard?

No. It measures about 42 mg/L (2.4 grains per gallon), which the USGS classes as soft.

What is the water hardness in Forest Grove in grains per gallon?

About 2.4 gpg. One grain per gallon equals 17.1 mg/L, so 42 mg/L divided by 17.1 gives 2.4.

Has the Forest Grove water system had EPA violations?

EPA records show no health-based violations for Forest Grove, City of since 2016. There were also 26 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 53 cities in Oregon

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.