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Well water hardness in Rolette County, North Dakota

23.6 gpg very hard

Private wells in Rolette County typically give very hard water: the median well sampled by the U.S. Geological Survey has 23.6 gpg (404 mg/L as CaCO₃).

<6060–120120–180>180 mg/L

Wells differ a lot, even next door: one in ten sampled wells had less than 226 mg/L and one in ten more than 662 mg/L. The figure comes from 61 wells and 71 samples taken between 1980 and 2022 (half of them by 1981).

Most samples are older than ten years. Groundwater hardness comes from the rock the well is drilled into and changes slowly, but your own well can be quite different, so treat this as a regional indication and test your water.

What this hardness means for a well household

How to test your well in North Dakota

Hardness is only one part of a well test. Federal health agencies advise every private well owner to test regularly:

Your county health department can tell you which certified laboratories accept private well samples.

Testing is your own responsibility: no state agency samples existing private wells routinely.

If no local lab suits you, mail-in kits from certified labs test a wider panel at home; they cost more than a state or county lab.

Treating hard well water

At this hardness an ion-exchange softener sized for your household is the usual answer. Test iron, manganese and pH first: well water often needs an iron filter or a pH correction in front of the softener.

Nearby counties

Towner County27.7 gpgMcHenry County14.6 gpgPierce County15 gpgBottineau County19 gpgWard County18.1 gpgWells County22.5 gpg

FAQ

How hard is well water in Rolette County, North Dakota?

The median well sampled by the USGS in Rolette County has 23.6 gpg (404 mg/L as CaCO₃), which is very hard. One in ten wells had less than 226 mg/L and one in ten more than 662 mg/L.

Is my own well the same?

Not necessarily. Hardness depends on the rock layer your well draws from and on its depth, so neighbouring wells can differ by a factor of two or more. Only a test of your own water tells you.

How often should I test my well in North Dakota?

Every year for coliform bacteria, nitrate, total dissolved solids and pH (EPA and CDC advice), and after floods, repairs or a change in taste or smell. Hardness, iron and manganese once, and again before you buy a softener.

Do I need a water softener for my well?

Yes, unless you are only passing through: scale damages appliances within a few years.

Where does this figure come from?

From 71 samples of 61 wells measured by the U.S. Geological Survey between 1980 and 2022, retrieved from the Water Quality Portal. We publish a county only when at least 10 wells were sampled.

Source and method

Computed by Water Hardness Atlas from USGS National Water Information System samples (characteristic "Hardness, Ca, Mg", sites of type well, samples since 1980), retrieved 2026-10-29 through the Water Quality Portal. For each well we take the median of its samples, then the median of all wells in the county; wells above 1,000 mg/L (oil, gas or mine brines) are left out. USGS data are in the U.S. public domain. Water Quality Portal query

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