How hard is the water in San Miguel County, CO?
11.1 grains per gallon
A softener will pay its way here.
The median hardness measured in San Miguel County, CO is 190 mg/L as calcium carbonate, which is 11.1 gpg. That is very hard on the USGS scale. It comes from 3,172 samples at 101 sites between 1991 and 2026, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 7 and 19.1 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 11.1 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 San Miguel 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 2.5 to 58.2 gpg
The softest single sample on record in San Miguel County was 43.5 mg/L and the hardest 996 mg/L, a 23-fold gap. The top quarter of sites read above 19.1 gpg and the bottom quarter below 7 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 51.1 gpg, rivers and lakes 11 gpg
1 groundwater samples from 1 wells put the median at 875 mg/L. 2,919 surface samples from 96 sites put it at 189 mg/L. In San Miguel County the wells come out 40.1 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 24,000-grain unit covers a week between regenerations. Expect about 242 lb of salt a year (7 bags of 40 lb, about $44), 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 $144 a year.
Sizing at 11.1 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 666 | 24,000 | 81 lb |
| 2 | 1,332 | 24,000 | 162 lb |
| 4 | 2,664 | 24,000 | 324 lb |
| 6 | 3,996 | 32,000 | 486 lb |
San Miguel County against the rest of Colorado
Among the 63 Colorado counties with data, San Miguel County is number 32 of 63 counting from the hardest. Across the whole country it is harder than 55% of counties.
Softest in Colorado: Larimer County at 0.4 gpg. Hardest: Mesa County at 143.7 gpg. Closest to San Miguel County: Yuma County (10.5), Alamosa County (12), Broomfield County (9.9).