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Well water hardness in Murray County, Oklahoma

18 gpg very hard

Private wells in Murray County typically give very hard water: the median well sampled by the U.S. Geological Survey has 18 gpg (309 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 230 mg/L and one in ten more than 408 mg/L. The figure comes from 39 wells and 47 samples taken between 1987 and 2012 (half of them by 2002).

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 Oklahoma

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

Use a certified laboratory: Oklahoma DEQ, State Environmental Laboratory Services and Laboratory Accreditation search.

Federal and state governments do not regulate privately owned wells in Oklahoma, so the owner alone is responsible for testing (DEQ fact sheet).

What a test costs (Oklahoma DEQ State Environmental Laboratory Services, fee schedule FY2027 (effective 2026-07-01))

Hardness, total (EPA 130.1)$25
Total coliform & E. coli P/A$33
Private well annual list: coliform/E. coli, nitrate/nitrite, pH, conductivity$75
Private well diagnostics list: annual list + calcium, copper, iron, manganese, sodium, hardness$175

Prices as printed by the lab (2026-06-30); check the current fee before you send a sample. Oklahoma DEQ State Environmental Laboratory Services, fee schedule FY2027 (effective 2026-07-01)

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

Johnston County20.3 gpgPottawatomie County7.9 gpgCleveland County7.6 gpgGrady County16.7 gpgOklahoma County12 gpgLincoln County11.1 gpg

FAQ

How hard is well water in Murray County, Oklahoma?

The median well sampled by the USGS in Murray County has 18 gpg (309 mg/L as CaCO₃), which is very hard. One in ten wells had less than 230 mg/L and one in ten more than 408 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 Oklahoma?

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 47 samples of 39 wells measured by the U.S. Geological Survey between 1987 and 2012, 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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