How hard is the water in Putnam County, OH?
17.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Putnam County, OH is 306 mg/L as calcium carbonate, which is 17.9 gpg. That is very hard on the USGS scale. It comes from 983 samples at 76 sites between 1996 and 2024, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 16.1 and 19.8 gpg. The whole middle of that range gives the same answer, so a test of your own tap is unlikely to change it. Confidence in the county figure: high (how it is measured).
What to do next
At 17.9 gpg a softener pays its way here. Before you buy, check the quoted unit's grain capacity against the sizing table below, and ask whether it regenerates on demand, which uses less salt than a timer. Call your utility for its own report if you are on city water.
More on sizing a softener for your household.
From 8.5 to 44.9 gpg
The softest single sample on record in Putnam County was 146 mg/L and the hardest 768 mg/L, a 5-fold gap. The top quarter of sites read above 19.8 gpg and the bottom quarter below 16.1 gpg.
Wells 24.6 gpg, rivers and lakes 17.9 gpg
5 groundwater samples from 3 wells put the median at 421 mg/L. 933 surface samples from 69 sites put it at 306 mg/L. In Putnam County the wells come out 6.7 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. A utility here that draws from the river can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 391 lb of salt a year (10 bags of 40 lb, about $70), and roughly 2,346 gallons of regeneration water. Installed, most units run $1,000 to $4,500; spread over 15 years with salt, that is about $170 a year.
Sizing at 17.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,074 | 24,000 | 131 lb |
| 2 | 2,148 | 24,000 | 261 lb |
| 4 | 4,296 | 32,000 | 523 lb |
| 6 | 6,444 | 48,000 | 784 lb |
Putnam County against the rest of Ohio
Among the 88 Ohio counties with data, Putnam County is number 47 of 88 counting from the hardest. Across the whole country it is harder than 78% of counties.
Softest in Ohio: Scioto County at 5.7 gpg. Hardest: Perry County at 113.3 gpg. Closest to Putnam County: Morrow County (18.1), Van Wert County (17.6), Harrison County (18.2).