How hard is the water in Dearborn, MI?

Tap water hardness
99mg/L
5.8gpg
Moderately hard

Reported by Dearborn · August 2025

MI typical
112 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
Utility report

Tap water in Dearborn has about 99 mg/L of hardness, which is 5.8 grains per gallon. On the USGS scale that counts as moderately hard. The number comes from Dearborn, dated August 2025.

Dearborn on the hardness scale, with nearby cities
060120180240300360+MI typical 112River Rouge: 96 mg/LRiver Rouge 96Detroit: 96 mg/LDetroit 96Taylor: 102 mg/LTaylor 102Melvindale: 104 mg/LMelvindale 104Allen Park: 104 mg/LAllen Park 104Dearborn Heights: 104 mg/LDearborn Heights 104Ecorse: 104 mg/LEcorse 104Inkster: 104 mg/LInkster 104Garden City: 104 mg/LGarden City 104Lincoln Park: 128 mg/LLincoln Park 128Dearborn 99mg/L as calcium carbonate060120180240300360+MI 112River Rouge: 96 mg/LRiver Rouge 96Melvindale: 104 mg/LMelvindale 104Allen Park: 104 mg/LAllen Park 104Dearborn Heights: 104 mg/LDearborn H. 104Ecorse: 104 mg/LEcorse 104Lincoln Park: 128 mg/LLincoln Pa. 12899 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Dearborn sits 13 mg/L below the typical Michigan figure of 112. Of the 10 nearest cities we track, 2 have softer water and 8 have harder. The range nearby runs from 96 mg/L in River Rouge to 128 in Lincoln Park.

What 99 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 Dearborn

3 people × 75 gallons a day × 5.8 gpg = 1,298 grains a day. A 24,000-grain unit regenerates about every 18 days.

Size it for your household

EPA record for Dearborn's water system

Dearborn · PWSID MI0001730

No health-based violations since 2016

Serves about 109,976 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

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 Dearborn water hard?

Somewhat. It measures about 99 mg/L (5.8 grains per gallon), which the USGS classes as moderately hard.

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

About 5.8 gpg. One grain per gallon equals 17.1 mg/L, so 99 mg/L divided by 17.1 gives 5.8.

What size water softener do I need in Dearborn?

For 3 people using 75 gallons each per day, 5.8 gpg works out to about 1,298 grains a day. A 24,000-grain softener covers that with a regeneration about every 18 days.

Has the Dearborn water system had EPA violations?

EPA records show no health-based violations for Dearborn since 2016.

Nearby cities

All 118 cities in Michigan

Hardness data: TapWaterData US Water Hardness (utility report, August 1, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.