How hard is the water in Eddy County, NM?
27.1 grains per gallon
A softener will pay its way here.
The median hardness measured in Eddy County, NM is 465 mg/L as calcium carbonate, which is 27.1 gpg. That is very hard on the USGS scale. It comes from 22 samples at 12 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 18.3 and 48.4 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: medium (how it is measured).
What to do next
At 27.1 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.
More on sizing a softener for your household.
From 1.4 to 109.3 gpg
The softest single sample on record in Eddy County was 23.4 mg/L and the hardest 1,871.6 mg/L, an 80-fold gap. The top quarter of sites read above 48.4 gpg and the bottom quarter below 18.3 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 27.1 gpg, rivers and lakes 108.7 gpg
22 groundwater samples from 12 wells put the median at 464.5 mg/L. 491 surface samples from 27 sites put it at 1860 mg/L. In Eddy County the rivers and lakes come out 81.6 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 40,000-grain unit covers a week between regenerations. Expect about 593 lb of salt a year (15 bags of 40 lb, about $107), 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 $207 a year.
Sizing at 27.1 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,626 | 24,000 | 198 lb |
| 2 | 3,252 | 24,000 | 396 lb |
| 4 | 6,504 | 48,000 | 791 lb |
| 6 | 9,756 | 80,000 | 1,187 lb |
Eddy County against the rest of New Mexico
Among the 33 New Mexico counties with data, Eddy County is number 7 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 Eddy County: Sierra County (27.6), Union County (26.4), Otero County (31.3).