Hardness
Very Hard
362.5 PPM · 21.2 GPG
Local water dashboard
Official source aggregationA source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Calhoun County.
At a glance
EPA quarter 2026Q2
Hardness
Very Hard
362.5 PPM · 21.2 GPG
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
0 mg/L
0% of action level
Utility match
1 system
Serves 722 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
362.5 PPM
Parts per million
362.5
mg/L as CaCO₃ equivalent
Grains per gallon
21.2
1 GPG ≈ 17.1 PPM
What this means at home
At 362.5 PPM, mineral scale can build up on fixtures and heating elements, reduce soap lather, and leave visible spotting. Hardness is primarily an aesthetic and appliance concern—not itself a tap-water safety rating.
USGS sites used
74
Nearest site
19.6 mi
Observation range
Jun 20, 2016–Oct 11, 2023
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: Coldwater Fen piezometer 1b-Branch County, MI (Well).USGS source documentation ↗
Regional context
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Tekonsha median
363 PPM
About the same1 indexed ZIP readings · Range 362.5–362.5 PPM
Michigan median
283 PPM
80 PPM higher504 indexed ZIP readings · Range 41.3–459.5 PPM
EPA benchmark screen
Available numerical results from associated SDWIS community water systems, compared with the applicable action level or federal MCL. Federal measured-value coverage is incomplete.
Lead (PB90)
0 mg/L
Reported Dec 31, 2023
Copper (CU90)
Not available
No numerical 90th-percentile result
Numerical coverage
1 comparable result
Missing values remain blank; absence is not treated as a pass.
Measured in mg/L
Local 0
EPA limit 0.015
100% line = listed limit
No violation record was returned for the associated systems in the imported lookback window beginning Jan 1, 2021.
No reported violation does not prove that every contaminant was tested or absent; SDWIS measured values are incomplete and lag state records.
Solutions matcher
Matched to Tekonsha ZIP 49092 using 362.5 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
362.5 PPM is 3× the high-hardness trigger used by this matcher.
Designed to reduce scale on fixtures, water heaters, glassware, and plumbing throughout the home.
Compare whole-house systemsAffiliate disclosure: we may earn a commission from qualifying purchases, at no added cost to you. Product matching is educational and does not replace certified water testing.
Frequently asked
EPA ECHO shows no active health-based violation for the associated systems in this reporting snapshot. This does not prove every contaminant is absent; federal records can lag and household plumbing can change tap conditions.
Nearby USGS observations produce an estimate of 362.5 PPM, or 21.2 grains per gallon, classified as very hard. This is not a household tap measurement.
At 362.5 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.