HardnessCheck

How hard is the water in Lassen County, CA?

4.6 grains per gallon

Optional: a softener helps, but plenty of homes skip it.

The median hardness measured in Lassen County, CA is 79 mg/L as calcium carbonate, which is 4.6 gpg. That is moderately hard on the USGS scale. It comes from 33 samples at 22 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 3.4 and 6.4 gpg. That spread crosses a decision line, so some homes here land on a different answer. A $10 test strip on your own tap settles it. Confidence in the county figure: high (how it is measured).

What to do next

At 4.6 gpg this is your call. Look for white film on glasses and crust on the shower head: if you see little of either, you can live without one. If you do want one, a 24,000-grain unit is enough, so ask for that size rather than a bigger one. Because Lassen County straddles a decision line, check your own tap with a $10 test strip before you spend anything.

More on when a softener is not worth it.

From 0.3 to 16.5 gpg

The softest single sample on record in Lassen County was 5 mg/L and the hardest 283 mg/L, a 57-fold gap. The top quarter of sites read above 6.4 gpg and the bottom quarter below 3.4 gpg.

Wells 4.6 gpg, rivers and lakes 6.4 gpg

33 groundwater samples from 22 wells put the median at 79.2 mg/L. 23 surface samples from 2 sites put it at 109.2 mg/L. In Lassen County the rivers and lakes come out 1.8 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. The two sources are close, so the county figure should hold whichever one your tap is on.

What a softener would cost to run

For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 101 lb of salt a year (3 bags of 40 lb, about $18), 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 $118 a year.

Sizing at 4.6 gpg

PeopleGrains a dayUnitSalt a year
127624,00034 lb
255224,00067 lb
41,10424,000134 lb
61,65624,000201 lb

Lassen County against the rest of California

Among the 58 California counties with data, Lassen County is number 48 of 58 counting from the hardest. Across the whole country it is harder than 29% of counties.

Softest in California: Sierra County at 1.7 gpg. Hardest: Calaveras County at 98.3 gpg. Closest to Lassen County: Placer County (4.6), Mono County (4.5), Shasta County (4.4).