How hard is the water in Maryville, MO?
Calculated from the utility's calcium and magnesium results · December 2020
- MO typical
- 121 mg/L
- EPA health violations since 2016
- 4
- Softener for 3 people
- 24k grain
- Data
- Calculated from utility data
The water in Maryville carries roughly 112 mg/L of dissolved calcium and magnesium, or 6.5 grains per gallon. That is moderately hard water. TapWaterData worked it out from the calcium and magnesium levels the local utility reports (December 2020).
At 112 mg/L, Maryville is close to the typical Missouri figure of 121 mg/L. Of the 10 nearest cities we track, 2 have softer water and 8 have harder. The range nearby runs from 106 mg/L in Smithville to 206 in St. Joseph.
What 112 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.
3 people × 75 gallons a day × 6.5 gpg = 1,474 grains a day. A 24,000-grain unit regenerates about every 16 days.
EPA record for Maryville's water system
4 health-based violations since 2016
Serves about 10,775 people from surface water.
- Health-based
- 4
- Monitoring or reporting
- 9
- Open now
- 0
EPA lists this system as serving Maryville.
| Contaminant or rule | Violations | Period | Status |
|---|---|---|---|
| Surface Water Treatment Rulefiltration and disinfection | 1 | 2025 | Resolved |
| Chlorite | 2 | 2024 | Resolved |
| Surface Water Treatment Rule (LT2)filtration and disinfection | 1 | 2022 | 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 Maryville water hard?
Somewhat. It measures about 112 mg/L (6.5 grains per gallon), which the USGS classes as moderately hard.
What is the water hardness in Maryville in grains per gallon?
About 6.5 gpg. One grain per gallon equals 17.1 mg/L, so 112 mg/L divided by 17.1 gives 6.5.
What size water softener do I need in Maryville?
For 3 people using 75 gallons each per day, 6.5 gpg works out to about 1,474 grains a day. A 24,000-grain softener covers that with a regeneration about every 16 days.
Has the Maryville water system had EPA violations?
EPA records show 4 health-based violations for Maryville PWS since 2016, involving Surface Water Treatment Rule, Chlorite, Surface Water Treatment Rule (LT2). There were also 9 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Savannah118 mg/LModerately hard
- St. Joseph206 mg/LVery hard
- Cameron143 mg/LHard
- Smithville106 mg/LModerately hard
- Kearney135 mg/LHard
- Excelsior Springs154 mg/LHard
- Parkville172 mg/LHard
- Chillicothe108 mg/LModerately hard
- Liberty162 mg/LHard
- Gladstone117 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (calculated from utility data, December 22, 2020), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.