How hard is the water in Sierra County, NM?
27.6 grains per gallon
A softener will pay its way here.
The median hardness measured in Sierra County, NM is 473 mg/L as calcium carbonate, which is 27.6 gpg. That is very hard on the USGS scale. It comes from 46 samples at 17 sites between 1994 and 2019, 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 20 and 33 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: high (how it is measured).
What to do next
At 27.6 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.
More on sizing a softener for your household.
From 3.4 to 74.8 gpg
The softest single sample on record in Sierra County was 57.8 mg/L and the hardest 1,280 mg/L, a 22-fold gap. The top quarter of sites read above 33 gpg and the bottom quarter below 20 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 27.6 gpg, rivers and lakes 12.1 gpg
46 groundwater samples from 17 wells put the median at 473 mg/L. 305 surface samples from 26 sites put it at 206.5 mg/L. In Sierra County the wells come out 15.5 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 40,000-grain unit covers a week between regenerations. Expect about 603 lb of salt a year (16 bags of 40 lb, about $109), 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 $209 a year.
Sizing at 27.6 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,656 | 24,000 | 201 lb |
| 2 | 3,312 | 24,000 | 403 lb |
| 4 | 6,624 | 48,000 | 806 lb |
| 6 | 9,936 | 80,000 | 1,209 lb |
Sierra County against the rest of New Mexico
Among the 33 New Mexico counties with data, Sierra County is number 6 of 33 counting from the hardest. Across the whole country it is harder than 93% of counties.
Softest in New Mexico: Rio Arriba County at 2.3 gpg. Hardest: Chaves County at 116.2 gpg. Closest to Sierra County: Eddy County (27.1), Union County (26.4), Otero County (31.3).