How hard is the water in Mohave County, AZ?
16.6 grains per gallon
A softener will pay its way here.
The median hardness measured in Mohave County, AZ is 285 mg/L as calcium carbonate, which is 16.6 gpg. That is very hard on the USGS scale. It comes from 1,387 samples at 639 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 9.9 and 26 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 16.6 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. Because Mohave 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 0.3 to 198.0 gpg
The softest single sample on record in Mohave County was 5 mg/L and the hardest 3,390 mg/L, a 678-fold gap. The top quarter of sites read above 26 gpg and the bottom quarter below 9.9 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 16.6 gpg, rivers and lakes 17.3 gpg
1,387 groundwater samples from 639 wells put the median at 285 mg/L. 635 surface samples from 60 sites put it at 295.3 mg/L. In Mohave County the rivers and lakes come out 0.7 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. 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 24,000-grain unit covers a week between regenerations. Expect about 364 lb of salt a year (10 bags of 40 lb, about $65), 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 $165 a year.
Sizing at 16.6 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 996 | 24,000 | 121 lb |
| 2 | 1,992 | 24,000 | 242 lb |
| 4 | 3,984 | 32,000 | 485 lb |
| 6 | 5,976 | 48,000 | 727 lb |
Mohave County against the rest of Arizona
Among the 15 Arizona counties with data, Mohave County is number 2 of 15 counting from the hardest. Across the whole country it is harder than 75% of counties.
Softest in Arizona: Navajo County at 9 gpg. Hardest: Yuma County at 28.7 gpg. Closest to Mohave County: Gila County (16.6), Coconino County (14.6), Yavapai County (14.3).