Hard water in Fort Riley, KS
Reported by Frusi Water Treatment Plant · October 2025
- KS typical
- 138 mg/L
- EPA health violations since 2016
- 3
- Softener for 3 people
- 24k grain
- Data
- Utility report
The water in Fort Riley carries roughly 140 mg/L of dissolved calcium and magnesium, or 8.2 grains per gallon. That is hard water. The number comes from Frusi Water Treatment Plant, dated October 2025.
At 140 mg/L, Fort Riley is close to the typical Kansas figure of 138 mg/L. Of the 10 nearest cities we track, 3 have softer water and 7 have harder. The range nearby runs from 76 mg/L in Emporia to 363 in McPherson.
What 140 mg/L means at home
Expect white crust on faucets and showerheads, plus spots on dishes that come out of the dishwasher.
Kettles collect scale quickly. Water heaters build up sediment at the bottom of the tank, which makes them work harder over time.
Soap and detergent need a little more to lather, and soap scum shows up in the tub.
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
At 140 mg/L most of the trouble is scale, and only a few things deal with it.
Ion-exchange water softener
The standard whole-house fix. It swaps calcium and magnesium for sodium or potassium and needs salt plus a drain. Size it with the calculator below.
Salt-free conditioner
No salt and no drain line. It changes how minerals form scale instead of removing them, so water still tests hard.
Reverse osmosis or carbon filter
Under-sink reverse osmosis removes minerals from drinking water only. Plain carbon filters improve taste but do not soften.
3 people × 75 gallons a day × 8.2 gpg = 1,843 grains a day. A 24,000-grain unit regenerates about every 13 days.
EPA record for Fort Riley's water system
3 health-based violations since 2016
Serves about 35,784 people from groundwater.
- Health-based
- 3
- Monitoring or reporting
- 0
- Open now
- 0
| Contaminant or rule | Violations | Period | Status |
|---|---|---|---|
| Total trihalomethanes (TTHM)a disinfection byproduct | 3 | 2018–2019 | 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 Fort Riley water hard?
Yes. It measures about 140 mg/L (8.2 grains per gallon), which the USGS classes as hard.
What is the water hardness in Fort Riley in grains per gallon?
About 8.2 gpg. One grain per gallon equals 17.1 mg/L, so 140 mg/L divided by 17.1 gives 8.2.
What size water softener do I need in Fort Riley?
For 3 people using 75 gallons each per day, 8.2 gpg works out to about 1,843 grains a day. A 24,000-grain softener covers that with a regeneration about every 13 days.
Has the Fort Riley water system had EPA violations?
EPA records show 3 health-based violations for Frusi Water Treatment Plant since 2016, involving Total trihalomethanes (TTHM).
Nearby cities
- Junction City168 mg/LHard
- Manhattan103 mg/LModerately hard
- Salina330 mg/LVery hard
- Emporia76 mg/LModerately hard
- Topeka145 mg/LHard
- McPherson363 mg/LVery hard
- Newton260 mg/LVery hard
- Lawrence142 mg/LHard
- El Dorado117 mg/LModerately hard
- Ottawa144 mg/LHard
Hardness data: TapWaterData US Water Hardness (utility report, October 16, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.