How hard is the water in Franklin, MA?

Tap water hardness
69mg/L
4.0gpg
Moderately hard

Reported by Franklin Water Department · March 2025

MA typical
38 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
Utility report

The water in Franklin carries roughly 69 mg/L of dissolved calcium and magnesium, or 4.0 grains per gallon. That is moderately hard water. The number comes from Franklin Water Department, dated March 2025.

Franklin on the hardness scale, with nearby cities
060120180240300360+MA typical 38Whitinsville: 28 mg/LWhitinsville 28Milford: 37 mg/LMilford 37Norwood: 46 mg/LNorwood 46Sharon: 47 mg/LSharon 47Foxborough: 48 mg/LFoxborough 48Mansfield Center: 50 mg/LMansfield Center 50Attleboro: 56 mg/LAttleboro 56Walpole: 66 mg/LWalpole 66North Attleborough: 71 mg/LNorth Attleborough 71Medfield: 95 mg/LMedfield 95Franklin 69mg/L as calcium carbonate060120180240300360+MA 38Milford: 37 mg/LMilford 37Foxborough: 48 mg/LFoxborough 48Mansfield Center: 50 mg/LMansfield. 50Walpole: 66 mg/LWalpole 66North Attleborough: 71 mg/LNorth Attl. 71Medfield: 95 mg/LMedfield 9569 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 69 mg/L, Franklin is 31 mg/L above the typical Massachusetts figure of 38. Of the 10 nearest cities we track, 8 have softer water and 2 have harder. The range nearby runs from 28 mg/L in Whitinsville to 95 in Medfield.

What 69 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 Franklin

3 people × 75 gallons a day × 4.0 gpg = 911 grains a day. A 24,000-grain unit regenerates about every 26 days.

Size it for your household

EPA record for Franklin's water system

Franklin Water Department · PWSID MA2101000

No health-based violations since 2016

Serves about 33,706 people from groundwater.

Health-based
0
Monitoring or reporting
1
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 Franklin water hard?

Somewhat. It measures about 69 mg/L (4.0 grains per gallon), which the USGS classes as moderately hard.

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

About 4.0 gpg. One grain per gallon equals 17.1 mg/L, so 69 mg/L divided by 17.1 gives 4.0.

What size water softener do I need in Franklin?

For 3 people using 75 gallons each per day, 4.0 gpg works out to about 911 grains a day. A 24,000-grain softener covers that with a regeneration about every 26 days.

Has the Franklin water system had EPA violations?

EPA records show no health-based violations for Franklin Water Department since 2016. 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, March 17, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.