State water index

Michigan water hardness

Search 382 indexed communities and 512 ZIP profiles, then compare the underlying utility, source, distance, and reporting context.

Median indexed hardness

283PPM

Very Hard

Indexed range 41.3–459.5 PPM

ZIP profiles: 512
Cities: 382
Matched utilities: 430
Counties: 82

Understanding Michigan

Why local comparisons matter here

Michigan is surrounded by the Great Lakes but also contains extensive glacial and bedrock groundwater systems, with distinct settings across both peninsulas.

In this index, very hard is the largest category, covering 431 of 504 profiles with hardness data. The state median is 283 PPM, but the full indexed range is 41.3–459.5 PPM.

State distribution

Hardness across indexed ZIPs

Counts describe published ZIP profiles, not a population-weighted statewide sample.

Soft · 0–60 PPM7

Moderately hard · 61–120 PPM34

Hard · 121–180 PPM32

Very hard · 181+ PPM431

Evidence coverage

What the current records support

Hardness estimate: 98%
Lead 90th percentile: 95%
Copper 90th percentile: 13%

324

Low-confidence hardness profiles

223

Nearest site more than 25 miles away

Reported source water

Utility source mix

Groundwater: 283
Surface water: 145
Groundwater influenced by surface water: 2

Highest medians

Hardest indexed cities

1. Coleman460 PPM
2. Edmore410 PPM
3. Lakeview410 PPM
4. Mount Pleasant410 PPM
5. Stanton410 PPM

Lowest medians

Softest indexed cities

City directory

Explore Michigan by city

Search by city or county, then sort by name, hardness, or ZIP coverage.

382 cities · 512 ZIP profiles

Search city or county

County

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382 cities found

Page 1 of 16

Addison

Lenawee County · 1 ZIP

377PPM

County	Median	Range	ZIP profiles
Montcalm County	410 PPM	408.5–410	5
Isabella County	410 PPM	410–410	2
Sanilac County	404 PPM	404–404	2
Tuscola County	404 PPM	403–404	3
Midland County	401 PPM	394–459.5	3
Gratiot County	399 PPM	392–408.5	6
Mason County	398 PPM	398–398	2
Ionia County	397 PPM	374–408.5	8
Lapeer County	396 PPM	283–403	6
Clinton County	394 PPM	374.5–403.5	7
Shiawassee County	392 PPM	283–403	7
Kent County	392 PPM	367–408.5	18

Why local comparisons matter here

Hardness across indexed ZIPs

What the current records support

Utility source mix

Hardest indexed cities

Softest indexed cities

Explore Michigan by city

Addison

Adrian

Ahmeek

Albion

Allegan

Allen Park

Allendale

Alma

Almont

Alpena

Alpha

Amasa

Ann Arbor

Armada

Ashley

Atlanta

Au Gres

Auburn

Auburn Hills

Augusta

Bad Axe

Baldwin

Bancroft

Bangor

Highest indexed county medians