How hard is the water in Smithville, MO?

Tap water hardness

106mg/L

6.2gpg

Moderately hardReports range 74–106

Calculated from the utility's calcium and magnesium results · April 2025

MO typical: 121 mg/L
EPA health violations since 2016: 2
Softener for 3 people: 24k grain
Data: Calculated from utility data

Smithville water measures 106 mg/L (6.2 gpg) of hardness, moderately hard by USGS standards. TapWaterData worked it out from the calcium and magnesium levels the local utility reports (April 2025). Reports for this system disagree, with values from 74 to 106 mg/L.

Smithville on the hardness scale, with nearby cities

Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 106 mg/L, Smithville is 15 mg/L below the typical Missouri figure of 121. None of the 10 nearest cities we track has softer water. The range nearby runs from 116 mg/L in North Kansas City to 206 in St. Joseph.

What 106 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 Smithville

3 people × 75 gallons a day × 6.2 gpg = 1,400 grains a day. A 24,000-grain unit regenerates about every 17 days.

Size it for your household

EPA record for Smithville's water system

Smithville PWS · PWSID MO1010748

2 health-based violations since 2016

Serves about 10,885 people from surface water.

Health-based: 2
Monitoring or reporting: 1
Open now: 0

EPA lists this system as serving Smithville.

Each dot is one health-based violation, placed at the start of its compliance period.

Contaminant or rule	Violations	Period	Status
Total trihalomethanes (TTHM)a disinfection byproduct	2	2016	Resolved

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 Smithville water hard?

Somewhat. It measures about 106 mg/L (6.2 grains per gallon), which the USGS classes as moderately hard.

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

About 6.2 gpg. One grain per gallon equals 17.1 mg/L, so 106 mg/L divided by 17.1 gives 6.2.

What size water softener do I need in Smithville?

For 3 people using 75 gallons each per day, 6.2 gpg works out to about 1,400 grains a day. A 24,000-grain softener covers that with a regeneration about every 17 days.

Has the Smithville water system had EPA violations?

EPA records show 2 health-based violations for Smithville PWS since 2016, involving Total trihalomethanes (TTHM). There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.

Nearby cities

All 90 cities in Missouri

Hardness data: TapWaterData US Water Hardness (calculated from utility data, April 28, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.