Hard water in Westerville, OH
Reported by Westerville City PWS · January 2025
- OH typical
- 113 mg/L
- EPA health violations since 2016
- 1
- Softener for 3 people
- 24k grain
- Data
- Utility report
Westerville water measures 124 mg/L (7.2 gpg) of hardness, hard by USGS standards. The number comes from Westerville City PWS, dated January 2025.
Westerville sits 11 mg/L above the typical Ohio figure of 113. None of the 10 nearest cities we track has harder water. The range nearby runs from 94 mg/L in Powell to 97 in Worthington.
What 124 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 124 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 × 7.2 gpg = 1,624 grains a day. A 24,000-grain unit regenerates about every 14 days.
EPA record for Westerville's water system
1 health-based violation since 2016
Serves about 39,000 people from surface water.
- Health-based
- 1
- Monitoring or reporting
- 0
- Open now
- 0
| Contaminant or rule | Violations | Period | Status |
|---|---|---|---|
| Total trihalomethanes (TTHM)a disinfection byproduct | 1 | 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 Westerville water hard?
Yes. It measures about 124 mg/L (7.2 grains per gallon), which the USGS classes as hard.
What is the water hardness in Westerville in grains per gallon?
About 7.2 gpg. One grain per gallon equals 17.1 mg/L, so 124 mg/L divided by 17.1 gives 7.2.
What size water softener do I need in Westerville?
For 3 people using 75 gallons each per day, 7.2 gpg works out to about 1,624 grains a day. A 24,000-grain softener covers that with a regeneration about every 14 days.
Has the Westerville water system had EPA violations?
EPA records show 1 health-based violation for Westerville City PWS since 2016, involving Total trihalomethanes (TTHM).
Nearby cities
- Worthington97 mg/LModerately hard
- Gahanna96 mg/LModerately hard
- New Albany97 mg/LModerately hard
- Powell94 mg/LModerately hard
- Columbus97 mg/LModerately hard
- Upper Arlington97 mg/LModerately hard
- Whitehall97 mg/LModerately hard
- Bexley97 mg/LModerately hard
- Grandview Heights97 mg/LModerately hard
- Dublin97 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (utility report, January 13, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.