How hard is the water in Davis County, UT?
9 grains per gallon
A softener is worth it here.
The median hardness measured in Davis County, UT is 154 mg/L as calcium carbonate, which is 9 gpg. That is hard on the USGS scale. It comes from 65 samples at 17 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 3.8 and 14.4 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 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 Davis 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 1.4 to 28.2 gpg
The softest single sample on record in Davis County was 24.7 mg/L and the hardest 482.5 mg/L, a 20-fold gap. The top quarter of sites read above 14.4 gpg and the bottom quarter below 3.8 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 9 gpg, rivers and lakes 16.6 gpg
65 groundwater samples from 17 wells put the median at 154 mg/L. 2,086 surface samples from 56 sites put it at 283.4 mg/L. In Davis County the rivers and lakes come out 7.6 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 196 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 9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 540 | 24,000 | 66 lb |
| 2 | 1,080 | 24,000 | 131 lb |
| 4 | 2,160 | 24,000 | 263 lb |
| 6 | 3,240 | 24,000 | 394 lb |
Davis County against the rest of Utah
Among the 29 Utah counties with data, Davis County is the softest. Across the whole country it is harder than 47% of counties.
Hardest: Emery County at 151.3 gpg. Closest to Davis County: Piute County (9.1), Garfield County (9.5), Duchesne County (10.3).