How hard is the water in Franklin County, MA?

2.2 grains per gallon

You do not need a softener here.

The median hardness measured in Franklin County, MA is 38 mg/L as calcium carbonate, which is 2.2 gpg. That is soft on the USGS scale. It comes from 370 samples at 15 sites between 1990 and 2023, drawn from every sampling site in the county, wells and surface water together.

How much it varies here

Half the sites came in between 1 and 3 gpg. The whole middle of that range gives the same answer, so a test of your own tap is unlikely to change it. Confidence in the county figure: high (how it is measured).

What to do next

You can skip the softener. At 2.2 gpg the most a softener would fix is the odd water spot. If a salesperson in Franklin County says otherwise, ask to see their reading in grains per gallon and compare it with this one.

More on when a softener is not worth it.

From 0.5 to 5.1 gpg

The softest single sample on record in Franklin County was 8 mg/L and the hardest 87.7 mg/L, an 11-fold gap. The top quarter of sites read above 3 gpg and the bottom quarter below 1 gpg.

Wells 4.1 gpg, rivers and lakes 1.8 gpg

2 groundwater samples from 2 wells put the median at 70 mg/L. 368 surface samples from 13 sites put it at 30.6 mg/L. In Franklin County the wells come out 2.3 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. The two sources are close, so the county figure should hold whichever one your tap is on.

Franklin County against the rest of Massachusetts

Among the 12 Massachusetts counties with data, Franklin County is number 10 of 12 counting from the hardest. Across the whole country it is harder than 17% of counties.

Softest in Massachusetts: Barnstable County at 1.3 gpg. Hardest: Berkshire County at 8.9 gpg. Closest to Franklin County: Norfolk County (2.4), Bristol County (2.6), Plymouth County (1.3).