Portland, ME water hardness

Tap water hardness
8mg/L
0.5gpg
SoftReports range 8–24

Reported by Portland Water District-Greater · October 2025

ME typical
16 mg/L
EPA health violations since 2016
0
Data
Utility report

The water in Portland carries roughly 8 mg/L of dissolved calcium and magnesium, or 0.5 grains per gallon. That is soft water. The number comes from Portland Water District-Greater, dated October 2025. Reports for this system disagree, with values from 8 to 24 mg/L.

Portland on the hardness scale, with nearby cities
060120180240300360+ME typical 16South Portland: 8 mg/LSouth Portland 8Gorham: 8 mg/LGorham 8Bath: 9 mg/LBath 9Saco: 14 mg/LSaco 14Brunswick: 14 mg/LBrunswick 14Topsham: 39 mg/LTopsham 39Kennebunk: 59 mg/LKennebunk 59Biddeford: 71 mg/LBiddeford 71Yarmouth: 76 mg/LYarmouth 76Auburn: 89 mg/LAuburn 89Portland 8mg/L as calcium carbonate060120180240300360+ME 16South Portland: 8 mg/LSouth Port. 8Gorham: 8 mg/LGorham 8Saco: 14 mg/LSaco 14Brunswick: 14 mg/LBrunswick 14Biddeford: 71 mg/LBiddeford 71Yarmouth: 76 mg/LYarmouth 768 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Portland sits close to the typical Maine figure of 16 mg/L. None of the 10 nearest cities we track has softer water. The range nearby runs from 8 mg/L in South Portland to 89 in Auburn.

What 8 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 8 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 Portland's water system

Portland Water District-Greater · PWSID ME0091300

No health-based violations since 2016

Serves about 135,068 people from surface water.

Health-based
0
Monitoring or reporting
6
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 Portland water hard?

No. It measures about 8 mg/L (0.5 grains per gallon), which the USGS classes as soft.

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

About 0.5 gpg. One grain per gallon equals 17.1 mg/L, so 8 mg/L divided by 17.1 gives 0.5.

Has the Portland water system had EPA violations?

EPA records show no health-based violations for Portland Water District-Greater since 2016. There were also 6 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 23 cities in Maine

Hardness data: TapWaterData US Water Hardness (utility report, October 3, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.