How hard is the water in Owensboro, KY?

Tap water hardness
116mg/L
6.8gpg
Moderately hardCounty estimate

County estimate from 205 water samples in Daviess County · July 2026

KY typical
134 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
County estimate

Water samples from around Owensboro put hardness at about 116 mg/L (6.8 gpg), which would be moderately hard on the USGS scale. Treat this as a rough guide: it is the median of 205 samples taken across Daviess County, mostly wells and streams, not a test of Owensboro's treated tap water.

Owensboro on the hardness scale, with nearby cities
060120180240300360+KY typical 134Paducah: 63 mg/LPaducah 63Hopkinsville: 86 mg/LHopkinsville 86Louisville: 134 mg/LLouisville 134St. Matthews: 134 mg/LSt. Matthews 134Bowling Green: 135 mg/LBowling Green 135Nicholasville: 160 mg/LNicholasville 160Radcliff: 186 mg/LRadcliff 186Elizabethtown: 186 mg/LElizabethtown 186Henderson: 198 mg/LHenderson 198Frankfort: 199 mg/LFrankfort 199Owensboro 116mg/L as calcium carbonate060120180240300360+KY 134Hopkinsville: 86 mg/LHopkinsvil. 86Louisville: 134 mg/LLouisville 134Bowling Green: 135 mg/LBowling Gr. 135Radcliff: 186 mg/LRadcliff 186Elizabethtown: 186 mg/LElizabetht. 186Henderson: 198 mg/LHenderson 198116 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Owensboro sits 18 mg/L below the typical Kentucky figure of 134. Of the 10 nearest cities we track, 2 have softer water and 8 have harder. The range nearby runs from 63 mg/L in Paducah to 199 in Frankfort.

What 116 mg/L means at home

You may see faint white spots on glasses and shower doors after the water dries.

Scale builds up slowly. A kettle or coffee maker needs descaling now and then, maybe every few months.

Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.

What to do about it

Optional. Plenty of households at this level live with it and descale the kettle now and then.

Water softener

Worth a look if spots on glass bother you, or if your tankless water heater manual asks for softer water.

Carbon filter

Improves taste and removes chlorine. It leaves calcium and magnesium in place.

Softener size for Owensboro

3 people × 75 gallons a day × 6.8 gpg = 1,526 grains a day. A 24,000-grain unit regenerates about every 15 days.

Size it for your household

EPA record for Owensboro's water system

Owensboro Municipal Utilities · PWSID KY0300336

No health-based violations since 2016

Serves about 60,473 people from groundwater.

Health-based
0
Monitoring or reporting
1
Open now
0

EPA lists this system as serving Owensboro.

Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.

Questions

Is Owensboro water hard?

Somewhat. It measures about 116 mg/L (6.8 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in Owensboro in grains per gallon?

About 6.8 gpg. One grain per gallon equals 17.1 mg/L, so 116 mg/L divided by 17.1 gives 6.8.

What size water softener do I need in Owensboro?

For 3 people using 75 gallons each per day, 6.8 gpg works out to about 1,526 grains a day. A 24,000-grain softener covers that with a regeneration about every 15 days.

Has the Owensboro water system had EPA violations?

EPA records show no health-based violations for Owensboro Municipal Utilities since 2016. There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.

Nearby cities

All 37 cities in Kentucky

Hardness data: TapWaterData US Water Hardness (county estimate, July 4, 2026), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.