How hard is the water in Romulus, MI?

Tap water hardness
92mg/L
5.4gpg
Moderately hard

Reported by Canton Township · September 2025

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

The water in Romulus carries roughly 92 mg/L of dissolved calcium and magnesium, or 5.4 grains per gallon. That is moderately hard water. The number comes from Canton Township, dated September 2025.

Romulus on the hardness scale, with nearby cities
060120180240300360+MI typical 112Wayne: 91 mg/LWayne 91Westland: 96 mg/LWestland 96Woodhaven: 96 mg/LWoodhaven 96Taylor: 102 mg/LTaylor 102Inkster: 104 mg/LInkster 104Garden City: 104 mg/LGarden City 104Allen Park: 104 mg/LAllen Park 104Dearborn Heights: 104 mg/LDearborn Heights 104Riverview: 109 mg/LRiverview 109Lincoln Park: 128 mg/LLincoln Park 128Romulus 92mg/L as calcium carbonate060120180240300360+MI 112Wayne: 91 mg/LWayne 91Westland: 96 mg/LWestland 96Taylor: 102 mg/LTaylor 102Inkster: 104 mg/LInkster 104Garden City: 104 mg/LGarden City 104Allen Park: 104 mg/LAllen Park 10492 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Romulus sits 20 mg/L below the typical Michigan figure of 112. Of the 10 nearest cities we track, 1 has softer water and 9 have harder. The range nearby runs from 91 mg/L in Wayne to 128 in Lincoln Park.

What 92 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 Romulus

3 people × 75 gallons a day × 5.4 gpg = 1,213 grains a day. A 24,000-grain unit regenerates about every 19 days.

Size it for your household

EPA record for Romulus's water system

Romulus · PWSID MI0005785

No health-based violations since 2016

Serves about 23,989 people from surface water.

Health-based
0
Monitoring or reporting
4
Open now
0

EPA lists Romulus as the system serving Romulus. The hardness figure above comes from a different system's report, which TapWaterData uses for Romulus.

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 Romulus water hard?

Somewhat. It measures about 92 mg/L (5.4 grains per gallon), which the USGS classes as moderately hard.

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

About 5.4 gpg. One grain per gallon equals 17.1 mg/L, so 92 mg/L divided by 17.1 gives 5.4.

What size water softener do I need in Romulus?

For 3 people using 75 gallons each per day, 5.4 gpg works out to about 1,213 grains a day. A 24,000-grain softener covers that with a regeneration about every 19 days.

Has the Romulus water system had EPA violations?

EPA records show no health-based violations for Romulus since 2016. There were also 4 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 118 cities in Michigan

Hardness data: TapWaterData US Water Hardness (utility report, September 8, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.