How hard is the water in Alamosa County, CO?
12 grains per gallon
A softener will pay its way here.
The median hardness measured in Alamosa County, CO is 205 mg/L as calcium carbonate, which is 12 gpg. That is very hard on the USGS scale. It comes from 41 samples at 31 sites between 1990 and 2026, 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 8 and 13.9 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 12 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 Alamosa 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 1.1 to 25.6 gpg
The softest single sample on record in Alamosa County was 18.9 mg/L and the hardest 438 mg/L, a 23-fold gap. The top quarter of sites read above 13.9 gpg and the bottom quarter below 8 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 12 gpg, rivers and lakes 3.7 gpg
41 groundwater samples from 31 wells put the median at 205 mg/L. 622 surface samples from 22 sites put it at 63.5 mg/L. In Alamosa County the wells come out 8.3 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. 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 262 lb of salt a year (7 bags of 40 lb, about $47), 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 $147 a year.
Sizing at 12 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 720 | 24,000 | 88 lb |
| 2 | 1,440 | 24,000 | 175 lb |
| 4 | 2,880 | 24,000 | 350 lb |
| 6 | 4,320 | 32,000 | 526 lb |
Alamosa County against the rest of Colorado
Among the 63 Colorado counties with data, Alamosa County is number 31 of 63 counting from the hardest. Across the whole country it is harder than 58% of counties.
Softest in Colorado: Larimer County at 0.4 gpg. Hardest: Mesa County at 143.7 gpg. Closest to Alamosa County: El Paso County (12.4), Clear Creek County (12.7), Kit Carson County (12.7).