How hard is the water in Kansas City, MO?

Tap water hardness
116mg/L
6.8gpg
Moderately hard

Reported by Kansas City PWS · October 2025

MO typical
121 mg/L
EPA health violations since 2016
1
Softener for 3 people
24k grain
Data
Utility report

The water in Kansas City carries roughly 116 mg/L of dissolved calcium and magnesium, or 6.8 grains per gallon. That is moderately hard water. The number comes from Kansas City PWS, dated October 2025.

Kansas City on the hardness scale, with nearby cities
060120180240300360+MO typical 121Lee's Summit: 97 mg/LLee's Summit 97Smithville: 106 mg/LSmithville 106North Kansas City: 116 mg/LNorth Kansas City 116Raytown: 116 mg/LRaytown 116Gladstone: 117 mg/LGladstone 117Independence: 118 mg/LIndependence 118Liberty: 162 mg/LLiberty 162Parkville: 172 mg/LParkville 172Grandview: 310 mg/LGrandview 310Blue Springs: 310 mg/LBlue Springs 310Kansas City 116mg/L as calcium carbonate060120180240300360+MO 121North Kansas City: 116 mg/LNorth Kans. 116Raytown: 116 mg/LRaytown 116Gladstone: 117 mg/LGladstone 117Independence: 118 mg/LIndependen. 118Liberty: 162 mg/LLiberty 162Parkville: 172 mg/LParkville 172116 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Kansas City sits close to the typical Missouri figure of 121 mg/L. Of the 10 nearest cities we track, 2 have softer water and 6 have harder. The range nearby runs from 97 mg/L in Lee's Summit to 310 in Grandview.

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 Kansas City

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 Kansas City's water system

Kansas City PWS · PWSID MO1010415

1 health-based violation since 2016

Serves about 553,295 people from surface water.

Health-based
1
Monitoring or reporting
3
Open now
1
20162017201820192020202120222023202420252026Surface Water Treatment Rule (LT2)'16'18'20'22'24'26Surface Water Treatment Rule (LT2)
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Surface Water Treatment Rule (LT2)filtration and disinfection12019Resolved

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 Kansas City 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 Kansas City 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 Kansas City?

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 Kansas City water system had EPA violations?

EPA records show 1 health-based violation for Kansas City PWS since 2016, involving Surface Water Treatment Rule (LT2). There were also 3 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 90 cities in Missouri

Hardness data: TapWaterData US Water Hardness (utility report, October 6, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.