How hard is the water in Somerset County, NJ?
8.9 grains per gallon
A softener is worth it here.
The median hardness measured in Somerset County, NJ is 153 mg/L as calcium carbonate, which is 8.9 gpg. That is hard on the USGS scale. It comes from 47 samples at 22 sites between 1990 and 2023, drawn from groundwater wells, which is what most taps and private wells in the county draw on.
How much it varies here
Half the sites came in between 6.1 and 13.7 gpg. That spread crosses a decision line, so some homes here land on a different answer. A $10 test strip on your own tap settles it. Confidence in the county figure: high (how it is measured).
What to do next
At 8.9 gpg a softener is worth getting, mainly to protect the water heater and cut soap use. Get at least two quotes, ask each installer what grain capacity they are fitting, and check it against the sizing table below. Because Somerset County straddles a decision line, check your own tap with a $10 test strip before you spend anything.
More on sizing a softener for your household.
From 3.7 to 47.7 gpg
The softest single sample on record in Somerset County was 63 mg/L and the hardest 817 mg/L, a 13-fold gap. The top quarter of sites read above 13.7 gpg and the bottom quarter below 6.1 gpg.
Wells 8.9 gpg, rivers and lakes 5.1 gpg
47 groundwater samples from 22 wells put the median at 152.8 mg/L. 1,142 surface samples from 37 sites put it at 86.5 mg/L. In Somerset County the wells come out 3.8 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. A utility here that draws from the river can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 195 lb of salt a year (5 bags of 40 lb, about $35), and roughly 2,346 gallons of regeneration water. Installed, most units run $1,000 to $4,500; spread over 15 years with salt, that is about $135 a year.
Sizing at 8.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 534 | 24,000 | 65 lb |
| 2 | 1,068 | 24,000 | 130 lb |
| 4 | 2,136 | 24,000 | 260 lb |
| 6 | 3,204 | 24,000 | 390 lb |
Somerset County against the rest of New Jersey
Among the 21 New Jersey counties with data, Somerset County is number 7 of 21 counting from the hardest. Across the whole country it is harder than 46% of counties.
Softest in New Jersey: Ocean County at 0.8 gpg. Hardest: Hudson County at 17.2 gpg. Closest to Somerset County: Passaic County (8.6), Hunterdon County (8.3), Morris County (7.4).