How hard is the water in Foster County, ND?
21.4 grains per gallon
A softener will pay its way here.
The median hardness measured in Foster County, ND is 367 mg/L as calcium carbonate, which is 21.4 gpg. That is very hard on the USGS scale. It comes from 7 samples at 6 sites between 1990 and 2016, 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 17 and 21.7 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: medium (how it is measured).
What to do next
At 21.4 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 9.5 to 43.3 gpg
The softest single sample on record in Foster County was 163 mg/L and the hardest 741.5 mg/L, a 5-fold gap. The top quarter of sites read above 21.7 gpg and the bottom quarter below 17 gpg.
Wells 21.4 gpg, rivers and lakes 19.1 gpg
7 groundwater samples from 6 wells put the median at 366.5 mg/L. 282 surface samples from 5 sites put it at 327 mg/L. In Foster 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.
What a softener would cost to run
For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 468 lb of salt a year (12 bags of 40 lb, about $84), 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 $184 a year.
Sizing at 21.4 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,284 | 24,000 | 156 lb |
| 2 | 2,568 | 24,000 | 312 lb |
| 4 | 5,136 | 40,000 | 625 lb |
| 6 | 7,704 | 64,000 | 937 lb |
Foster County against the rest of North Dakota
Among the 53 North Dakota counties with data, Foster County is number 22 of 53 counting from the hardest. Across the whole country it is harder than 87% of counties.
Softest in North Dakota: Hettinger County at 1.1 gpg. Hardest: Walsh County at 54 gpg. Closest to Foster County: Traill County (21.4), Richland County (21.3), Cass County (21.2).