Leominster, MA water hardness

Tap water hardness
10mg/L
0.6gpg
Soft

Reported by Leominster Water Division · September 2025

MA typical
38 mg/L
EPA health violations since 2016
2
Data
Utility report

Tap water in Leominster has about 10 mg/L of hardness, which is 0.6 grains per gallon. On the USGS scale that counts as soft. The number comes from Leominster Water Division, dated September 2025.

Leominster on the hardness scale, with nearby cities
060120180240300360+MA typical 38Clinton: 14 mg/LClinton 14Fitchburg: 41 mg/LFitchburg 41Gardner: 41 mg/LGardner 41Worcester: 42 mg/LWorcester 42Lowell: 43 mg/LLowell 43Framingham: 52 mg/LFramingham 52West Concord: 57 mg/LWest Concord 57Marlborough: 67 mg/LMarlborough 67Maynard: 86 mg/LMaynard 86Northborough: 110 mg/LNorthborough 110Leominster 10mg/L as calcium carbonate060120180240300360+MA 38Clinton: 14 mg/LClinton 14Fitchburg: 41 mg/LFitchburg 41Gardner: 41 mg/LGardner 41Marlborough: 67 mg/LMarlborough 67Maynard: 86 mg/LMaynard 86Northborough: 110 mg/LNorthborou. 11010 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 10 mg/L, Leominster is 28 mg/L below the typical Massachusetts figure of 38. None of the 10 nearest cities we track has softer water. The range nearby runs from 14 mg/L in Clinton to 110 in Northborough.

What 10 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 10 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 Leominster's water system

Leominster Water Division · PWSID MA2153000

2 health-based violations since 2016

Serves about 41,683 people from surface water.

Health-based
2
Monitoring or reporting
1
Open now
0
20162017201820192020202120222023202420252026Haloacetic acids (HAA5)'16'18'20'22'24'26Haloacetic acids (HAA5)
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Haloacetic acids (HAA5)a disinfection byproduct22018Resolved

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 Leominster water hard?

No. It measures about 10 mg/L (0.6 grains per gallon), which the USGS classes as soft.

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

About 0.6 gpg. One grain per gallon equals 17.1 mg/L, so 10 mg/L divided by 17.1 gives 0.6.

Has the Leominster water system had EPA violations?

EPA records show 2 health-based violations for Leominster Water Division since 2016, involving Haloacetic acids (HAA5). There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.

Nearby cities

All 104 cities in Massachusetts

Hardness data: TapWaterData US Water Hardness (utility report, September 2, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.