How hard is the water in Toledo, OH?

Tap water hardness
76mg/L
4.4gpg
Moderately hard

Reported by Toledo City of · September 2025

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

Toledo water measures 76 mg/L (4.4 gpg) of hardness, moderately hard by USGS standards. The number comes from Toledo City of, dated September 2025.

Toledo on the hardness scale, with nearby cities
060120180240300360+OH typical 113Oberlin: 50 mg/LOberlin 50Perrysburg: 85 mg/LPerrysburg 85Waterville: 110 mg/LWaterville 110Findlay: 138 mg/LFindlay 138Lorain: 220 mg/LLorain 220Sandusky: 260 mg/LSandusky 260Bowling Green: 265 mg/LBowling Green 265Lima: 301 mg/LLima 301Marion: 311 mg/LMarion 311Bryan: 380 mg/LBryan 380Toledo 76mg/L as calcium carbonate060120180240300360+OH 113Perrysburg: 85 mg/LPerrysburg 85Waterville: 110 mg/LWaterville 110Findlay: 138 mg/LFindlay 138Sandusky: 260 mg/LSandusky 260Bowling Green: 265 mg/LBowling Gr. 265Bryan: 380 mg/LBryan 38076 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 76 mg/L, Toledo is 37 mg/L below the typical Ohio figure of 113. Of the 10 nearest cities we track, 1 has softer water and 9 have harder. The range nearby runs from 50 mg/L in Oberlin to 380 in Bryan.

What 76 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 Toledo

3 people × 75 gallons a day × 4.4 gpg = 999 grains a day. A 24,000-grain unit regenerates about every 24 days.

Size it for your household

EPA record for Toledo's water system

Toledo City of · PWSID OH4801411

1 health-based violation since 2016

Serves about 360,000 people from surface water.

Health-based
1
Monitoring or reporting
3
Open now
0
20162017201820192020202120222023202420252026Surface Water Treatment Rule'16'18'20'22'24'26Surface Water Treatment Rule
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Surface Water Treatment Rulefiltration and disinfection12023Resolved

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 Toledo water hard?

Somewhat. It measures about 76 mg/L (4.4 grains per gallon), which the USGS classes as moderately hard.

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

About 4.4 gpg. One grain per gallon equals 17.1 mg/L, so 76 mg/L divided by 17.1 gives 4.4.

What size water softener do I need in Toledo?

For 3 people using 75 gallons each per day, 4.4 gpg works out to about 999 grains a day. A 24,000-grain softener covers that with a regeneration about every 24 days.

Has the Toledo water system had EPA violations?

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

Nearby cities

All 108 cities in Ohio

Hardness data: TapWaterData US Water Hardness (utility report, September 15, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.