How hard is the water in Tillamook County, OR?

2.2 grains per gallon

You do not need a softener here.

The median hardness measured in Tillamook County, OR is 37 mg/L as calcium carbonate, which is 2.2 gpg. That is soft on the USGS scale. It comes from 224 samples at 68 sites between 1990 and 2024, 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 1.1 and 3.2 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

You can skip the softener. At 2.2 gpg the most a softener would fix is the odd water spot. If a salesperson in Tillamook 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 0.1 to 12.9 gpg

The softest single sample on record in Tillamook County was 1.6 mg/L and the hardest 221.5 mg/L, a 138-fold gap. The top quarter of sites read above 3.2 gpg and the bottom quarter below 1.1 gpg. So even in a soft county, a handful of wells here produce water hard enough to scale a heater.

Wells 2.2 gpg, rivers and lakes 1.6 gpg

224 groundwater samples from 68 wells put the median at 37.4 mg/L. 304 surface samples from 60 sites put it at 27.2 mg/L. In Tillamook County the wells come out 0.6 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. The two sources are close, so the county figure should hold whichever one your tap is on.

Tillamook County against the rest of Oregon

Among the 36 Oregon counties with data, Tillamook County is number 34 of 36 counting from the hardest. Across the whole country it is harder than 17% of counties.

Softest in Oregon: Columbia County at 1.4 gpg. Hardest: Malheur County at 17.8 gpg. Closest to Tillamook County: Clatsop County (2.2), Lake County (2.3), Curry County (2.4).