How hard is the water in Humboldt County, IA?
24 grains per gallon
A softener will pay its way here.
The median hardness measured in Humboldt County, IA is 410 mg/L as calcium carbonate, which is 24 gpg. That is very hard on the USGS scale. It comes from 5 samples at 5 sites between 1990 and 2005, 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 22.8 and 25 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 24 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 20.4 to 28.0 gpg
The softest single sample on record in Humboldt County was 350 mg/L and the hardest 480 mg/L, a 1-fold gap. The top quarter of sites read above 25 gpg and the bottom quarter below 22.8 gpg.
What a softener would cost to run
For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 523 lb of salt a year (14 bags of 40 lb, about $94), 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 $194 a year.
Sizing at 24 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,440 | 24,000 | 175 lb |
| 2 | 2,880 | 24,000 | 350 lb |
| 4 | 5,760 | 48,000 | 701 lb |
| 6 | 8,640 | 64,000 | 1,051 lb |
Humboldt County against the rest of Iowa
Among the 93 Iowa counties with data, Humboldt County is number 20 of 93 counting from the hardest. Across the whole country it is harder than 91% of counties.
Softest in Iowa: Taylor County at 8.2 gpg. Hardest: Pocahontas County at 45.3 gpg. Closest to Humboldt County: Ida County (23.7), Sac County (23.7), Crawford County (24.4).