How hard is the water in Eddy County, ND?
15.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Eddy County, ND is 269 mg/L as calcium carbonate, which is 15.7 gpg. That is very hard on the USGS scale. It comes from 59 samples at 49 sites between 1990 and 2024, 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 13.4 and 21.3 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
At 15.7 gpg a softener pays its way here. Before you buy, check the quoted unit's grain capacity against the sizing table below, and ask whether it regenerates on demand, which uses less salt than a timer. Call your utility for its own report if you are on city water.
More on sizing a softener for your household.
From 5.8 to 50.6 gpg
The softest single sample on record in Eddy County was 98.6 mg/L and the hardest 867 mg/L, a 9-fold gap. The top quarter of sites read above 21.3 gpg and the bottom quarter below 13.4 gpg.
Wells 15.7 gpg, rivers and lakes 21.4 gpg
59 groundwater samples from 49 wells put the median at 269 mg/L. 200 surface samples from 16 sites put it at 367 mg/L. In Eddy County the rivers and lakes come out 5.7 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. A utility here that draws from the aquifer 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 343 lb of salt a year (9 bags of 40 lb, about $62), 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 $162 a year.
Sizing at 15.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 942 | 24,000 | 115 lb |
| 2 | 1,884 | 24,000 | 229 lb |
| 4 | 3,768 | 32,000 | 458 lb |
| 6 | 5,652 | 40,000 | 688 lb |
Eddy County against the rest of North Dakota
Among the 53 North Dakota counties with data, Eddy County is number 38 of 53 counting from the hardest. Across the whole country it is harder than 71% of counties.
Softest in North Dakota: Hettinger County at 1.1 gpg. Hardest: Walsh County at 54 gpg. Closest to Eddy County: Mountrail County (15.5), Renville County (16), McKenzie County (16.4).