How hard is the water in Island County, WA?
20.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Island County, WA is 355 mg/L as calcium carbonate, which is 20.7 gpg. That is very hard on the USGS scale. It comes from 43 samples at 34 sites between 1994 and 2014, 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 12.1 and 53.7 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 20.7 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 5.7 to 86.5 gpg
The softest single sample on record in Island County was 98.4 mg/L and the hardest 1,480 mg/L, a 15-fold gap. The top quarter of sites read above 53.7 gpg and the bottom quarter below 12.1 gpg.
Wells 20.7 gpg, rivers and lakes 10.2 gpg
43 groundwater samples from 34 wells put the median at 355 mg/L. 19 surface samples from 6 sites put it at 174.8 mg/L. In Island County the wells come out 10.5 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 32,000-grain unit covers a week between regenerations. Expect about 453 lb of salt a year (12 bags of 40 lb, about $82), 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 $182 a year.
Sizing at 20.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,242 | 24,000 | 151 lb |
| 2 | 2,484 | 24,000 | 302 lb |
| 4 | 4,968 | 40,000 | 604 lb |
| 6 | 7,452 | 64,000 | 907 lb |
Island County against the rest of Washington
Among the 38 Washington counties with data, Island County is the hardest. Across the whole country it is harder than 85% of counties.
Softest in Washington: Chelan County at 0.6 gpg. Closest to Island County: Franklin County (15.3), Adams County (14.7), Grant County (12.2).