How hard is the water in Cavalier County, ND?
23.4 grains per gallon
A softener will pay its way here.
The median hardness measured in Cavalier County, ND is 401 mg/L as calcium carbonate, which is 23.4 gpg. That is very hard on the USGS scale. It comes from 159 samples at 16 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 16.8 and 32.1 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 23.4 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 7.7 to 94.6 gpg
The softest single sample on record in Cavalier County was 132.5 mg/L and the hardest 1,620 mg/L, a 12-fold gap. The top quarter of sites read above 32.1 gpg and the bottom quarter below 16.8 gpg.
Wells 30.2 gpg, rivers and lakes 22.7 gpg
13 groundwater samples from 3 wells put the median at 517 mg/L. 146 surface samples from 13 sites put it at 388 mg/L. In Cavalier County the wells come out 7.5 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 32,000-grain unit covers a week between regenerations. Expect about 512 lb of salt a year (13 bags of 40 lb, about $92), 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 $192 a year.
Sizing at 23.4 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,404 | 24,000 | 171 lb |
| 2 | 2,808 | 24,000 | 342 lb |
| 4 | 5,616 | 40,000 | 683 lb |
| 6 | 8,424 | 64,000 | 1,025 lb |
Cavalier County against the rest of North Dakota
Among the 53 North Dakota counties with data, Cavalier County is number 15 of 53 counting from the hardest. Across the whole country it is harder than 90% of counties.
Softest in North Dakota: Hettinger County at 1.1 gpg. Hardest: Walsh County at 54 gpg. Closest to Cavalier County: LaMoure County (23.3), Barnes County (24.4), Nelson County (22.2).