How hard is the water in Wilmington, MA?

Tap water hardness
68mg/L
4.0gpg
Moderately hardReports range 68–80

Reported by Tewksbury Water Department · September 2025

MA typical
38 mg/L
EPA health violations since 2016
1
Softener for 3 people
24k grain
Data
Utility report

Wilmington water measures 68 mg/L (4.0 gpg) of hardness, moderately hard by USGS standards. The number comes from Tewksbury Water Department, dated September 2025. Reports for this system disagree, with values from 68 to 80 mg/L.

Wilmington on the hardness scale, with nearby cities
060120180240300360+MA typical 38Stoneham: 16 mg/LStoneham 16Winchester: 20 mg/LWinchester 20Reading: 22 mg/LReading 22Lexington: 33 mg/LLexington 33Andover: 38 mg/LAndover 38Wakefield: 51 mg/LWakefield 51Pinehurst: 62 mg/LPinehurst 62Lynnfield: 72 mg/LLynnfield 72Woburn: 99 mg/LWoburn 99Burlington: 104 mg/LBurlington 104Wilmington 68mg/L as calcium carbonate060120180240300360+MA 38Reading: 22 mg/LReading 22Andover: 38 mg/LAndover 38Wakefield: 51 mg/LWakefield 51Pinehurst: 62 mg/LPinehurst 62Woburn: 99 mg/LWoburn 99Burlington: 104 mg/LBurlington 10468 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Wilmington sits 30 mg/L above the typical Massachusetts figure of 38. Of the 10 nearest cities we track, 7 have softer water and 3 have harder. The range nearby runs from 16 mg/L in Stoneham to 104 in Burlington.

What 68 mg/L means at home

You may see faint white spots on glasses and shower doors after the water dries.

Scale builds up slowly. A kettle or coffee maker needs descaling now and then, maybe every few months.

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

Optional. Plenty of households at this level live with it and descale the kettle now and then.

Water softener

Worth a look if spots on glass bother you, or if your tankless water heater manual asks for softer water.

Carbon filter

Improves taste and removes chlorine. It leaves calcium and magnesium in place.

Softener size for Wilmington

3 people × 75 gallons a day × 4.0 gpg = 900 grains a day. A 24,000-grain unit regenerates about every 26 days.

Size it for your household

EPA record for Wilmington's water system

Wilmington Water Dept · PWSID MA3342000

1 health-based violation since 2016

Serves about 21,654 people from surface water.

Health-based
1
Monitoring or reporting
0
Open now
0

EPA lists Wilmington Water Dept as the system serving Wilmington. The hardness figure above comes from a different system's report, which TapWaterData uses for Wilmington.

20162017201820192020202120222023202420252026Total Coliform Rule'16'18'20'22'24'26Total Coliform Rule
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Total Coliform Rulebacteria12022Resolved

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 Wilmington water hard?

Somewhat. It measures about 68 mg/L (4.0 grains per gallon), which the USGS classes as moderately hard.

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

About 4.0 gpg. One grain per gallon equals 17.1 mg/L, so 68 mg/L divided by 17.1 gives 4.0.

What size water softener do I need in Wilmington?

For 3 people using 75 gallons each per day, 4.0 gpg works out to about 900 grains a day. A 24,000-grain softener covers that with a regeneration about every 26 days.

Has the Wilmington water system had EPA violations?

EPA records show 1 health-based violation for Wilmington Water Dept since 2016, involving Total Coliform Rule.

Nearby cities

All 104 cities in Massachusetts

Hardness data: TapWaterData US Water Hardness (utility report, September 28, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.