State distribution
Hardness across indexed ZIPs
Counts describe published ZIP profiles, not a population-weighted statewide sample.
Soft · 0–60 PPM0
Moderately hard · 61–120 PPM25
Hard · 121–180 PPM31
Very hard · 181+ PPM106
State water index
Ohio water hardness
Search 119 indexed communities and 162 ZIP profiles, then compare the underlying utility, source, distance, and reporting context.
Median indexed hardness
226PPM
Very Hard
Indexed range 77.2–387 PPM
- ZIP profiles
- 162
- Cities
- 119
- Matched utilities
- 119
- Counties
- 65
Understanding Ohio
Why local comparisons matter here
Ohio combines Lake Erie and river-supplied cities with glacial and bedrock aquifers across the interior and Appalachian southeast.
In this index, very hard is the largest category, covering 106 of 162 profiles with hardness data. The state median is 226 PPM, but the full indexed range is 77.2–387 PPM.
Evidence coverage
What the current records support
- Hardness estimate
- 100%
- Lead 90th percentile
- 100%
- Copper 90th percentile
- 86%
36
Low-confidence hardness profiles
35
Nearest site more than 25 miles away
Reported source water
Utility source mix
- Surface water
- 68
- Groundwater
- 50
- Groundwater influenced by surface water
- 1
Highest medians
Hardest indexed cities
- 1. Kenton387 PPM
- 2. Bellefontaine380 PPM
- 3. Circleville380 PPM
- 4. Pickerington380 PPM
- 5. Wapakoneta380 PPM
Lowest medians
Softest indexed cities
- 1. Lakewood77 PPM
- 2. Berea79 PPM
- 3. North Ridgeville90 PPM
- 4. Avon101 PPM
- 5. Warren109 PPM
City directory
Explore Ohio by city
Search by city or county, then sort by name, hardness, or ZIP coverage.
119 cities · 162 ZIP profiles
119 cities found
Page 1 of 5
Alliance
Stark County · 1 ZIP
137PPM
Single indexed valueNo active flag
Amherst
Lorain County · 1 ZIP
164PPM
Single indexed valueNo active flag
Ashland
Ashland County · 1 ZIP
215PPM
Single indexed valueNo active flag
Aurora
Portage County · 1 ZIP
112PPM
Single indexed valueNo active flag
Avon
Lorain County · 1 ZIP
101PPM
Single indexed valueNo active flag
Avon Lake
Lorain County · 1 ZIP
164PPM
Single indexed valueNo active flag
Barnesville
Belmont County · 1 ZIP
173PPM
Single indexed valueNo active flag
Bellbrook
Greene County · 1 ZIP
365PPM
Single indexed valueNo active flag
Bellefontaine
Logan County · 1 ZIP
380PPM
Single indexed valueNo active flag
Bellevue
Huron County · 1 ZIP
200PPM
Single indexed valueNo active flag
Belpre
Washington County · 1 ZIP
110PPM
Single indexed valueNo active flag
Berea
Cuyahoga County · 1 ZIP
79PPM
Single indexed valueNo active flag
Berlin
Holmes County · 2 ZIPs
253PPM
Range 238.5–267No active flag
Bowling Green
Wood County · 2 ZIPs
226PPM
Single indexed valueNo active flag
Brilliant
Jefferson County · 1 ZIP
172PPM
Single indexed valueNo active flag
Brookville
Montgomery County · 1 ZIP
336PPM
Single indexed valueNo active flag
Bryan
Williams County · 1 ZIP
335PPM
Single indexed valueNo active flag
Bucyrus
Crawford County · 1 ZIP
228PPM
Single indexed valueNo active flag
Byesville
Guernsey County · 1 ZIP
206PPM
Single indexed valueNo active flag
Canal Fulton
Stark County · 1 ZIP
204PPM
Single indexed valueNo active flag
Canfield
Mahoning County · 1 ZIP
121PPM
Single indexed valueNo active flag
Chardon
Geauga County · 1 ZIP
164PPM
Single indexed valueNo active flag
Chauncey
Athens County · 1 ZIP
153PPM
Single indexed valueNo active flag
Chillicothe
Ross County · 1 ZIP
367PPM
Single indexed valueNo active flag
County comparison
Highest indexed county medians
| County | Median | Range | ZIP profiles |
|---|---|---|---|
| Hardin County | 387 PPM | 387–387 | 1 |
| Pickaway County | 380 PPM | 379.5–379.5 | 1 |
| Logan County | 380 PPM | 380–380 | 1 |
| Auglaize County | 380 PPM | 379.5–379.5 | 1 |
| Champaign County | 379 PPM | 378.5–378.5 | 1 |
| Clark County | 369 PPM | 367–371 | 7 |
| Pike County | 369 PPM | 369–369 | 1 |
| Ross County | 367 PPM | 367–367 | 1 |
| Fairfield County | 366 PPM | 352–380 | 2 |
| Greene County | 366 PPM | 364.5–367 | 2 |
| Clermont County | 364 PPM | 363–364.5 | 2 |
| Butler County | 350 PPM | 336–364 | 2 |