How hard is the water in Petersburg Borough, AK?

0.3 grains per gallon

You do not need a softener here.

The median hardness measured in Petersburg Borough, AK is 5 mg/L as calcium carbonate, which is 0.3 gpg. That is soft on the USGS scale. It comes from 10 samples at 2 sites between 2005 and 2006, drawn from every sampling site in the county, wells and surface water together.

How much it varies here

Half the sites came in between 0.2 and 0.3 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 0.3 gpg the most a softener would fix is the odd water spot. If a salesperson in Petersburg Borough 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 0.4 gpg

The softest single sample on record in Petersburg Borough was 3.5 mg/L and the hardest 6.4 mg/L, a 2-fold gap. The top quarter of sites read above 0.3 gpg and the bottom quarter below 0.2 gpg.

Petersburg Borough against the rest of Alaska

Among the 22 Alaska counties with data, Petersburg Borough is the softest. Across the whole country it is harder than 0% of counties.

Hardest: Southeast Fairbanks Census Area at 16.3 gpg. Closest to Petersburg Borough: Sitka City and Borough (0.9), Ketchikan Gateway Borough (0.9), Lake and Peninsula Borough (1.3).