How hard is the water in Chelan County, WA?
0.6 grains per gallon
You do not need a softener here.
The median hardness measured in Chelan County, WA is 10 mg/L as calcium carbonate, which is 0.6 gpg. That is soft on the USGS scale. It comes from 7 samples at 2 sites between 2009 and 2010, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 0.4 and 0.7 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: low (how it is measured).
What to do next
You can skip the softener. At 0.6 gpg the most a softener would fix is the odd water spot. If a salesperson in Chelan County says otherwise, ask to see their reading in grains per gallon and compare it with this one.
More on when a softener is not worth it.
From 0.2 to 0.9 gpg
The softest single sample on record in Chelan County was 3.4 mg/L and the hardest 15.9 mg/L, a 5-fold gap. The top quarter of sites read above 0.7 gpg and the bottom quarter below 0.4 gpg.
Chelan County against the rest of Washington
Among the 38 Washington counties with data, Chelan County is the softest. Across the whole country it is harder than 3% of counties.
Hardest: Island County at 20.7 gpg. Closest to Chelan County: Lewis County (0.9), Jefferson County (1.4), Cowlitz County (1.6).