How hard is the water in Harper Woods, MI?

Tap water hardness
95mg/L
5.5gpg
Moderately hard

Reported by Detroit City of · September 2025

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

Tap water in Harper Woods has about 95 mg/L of hardness, which is 5.5 grains per gallon. On the USGS scale that counts as moderately hard. The number comes from Detroit City of, dated September 2025.

Harper Woods on the hardness scale, with nearby cities
060120180240300360+MI typical 112Hamtramck: 87 mg/LHamtramck 87Grosse Pointe: 95 mg/LGrosse Pointe 95Grosse Pointe Park: 95 mg/LGrosse Pointe Park 95Warren: 95 mg/LWarren 95Detroit: 96 mg/LDetroit 96St. Clair Shores: 101 mg/LSt. Clair Shores 101Roseville: 101 mg/LRoseville 101Fraser: 101 mg/LFraser 101Grosse Pointe Farms: 110 mg/LGrosse Pointe Farms 110Eastpointe: 266 mg/LEastpointe 266Harper Woods 95mg/L as calcium carbonate060120180240300360+MI 112Grosse Pointe: 95 mg/LGrosse Poi. 95Grosse Pointe Park: 95 mg/LGrosse Poi. 95St. Clair Shores: 101 mg/LSt. Clair. 101Roseville: 101 mg/LRoseville 101Grosse Pointe Farms: 110 mg/LGrosse Poi. 110Eastpointe: 266 mg/LEastpointe 26695 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 95 mg/L, Harper Woods is 17 mg/L below the typical Michigan figure of 112. Of the 10 nearest cities we track, 1 has softer water and 6 have harder. The range nearby runs from 87 mg/L in Hamtramck to 266 in Eastpointe.

What 95 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 Harper Woods

3 people × 75 gallons a day × 5.5 gpg = 1,246 grains a day. A 24,000-grain unit regenerates about every 19 days.

Size it for your household

EPA record for Harper Woods's water system

Harper Woods · PWSID MI0003020

1 health-based violation since 2016

Serves about 14,236 people from surface water.

Health-based
1
Monitoring or reporting
4
Open now
0

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

20162017201820192020202120222023202420252026Lead and Copper Rule'16'18'20'22'24'26Lead and Copper Rule
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Lead and Copper Rulecorrosion control and lead sampling12023Resolved

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 Harper Woods water hard?

Somewhat. It measures about 95 mg/L (5.5 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in Harper Woods in grains per gallon?

About 5.5 gpg. One grain per gallon equals 17.1 mg/L, so 95 mg/L divided by 17.1 gives 5.5.

What size water softener do I need in Harper Woods?

For 3 people using 75 gallons each per day, 5.5 gpg works out to about 1,246 grains a day. A 24,000-grain softener covers that with a regeneration about every 19 days.

Has the Harper Woods water system had EPA violations?

EPA records show 1 health-based violation for Harper Woods since 2016, involving Lead and Copper Rule. 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 3, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.