Hardness
Hard
179.5 PPM · 10.5 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 Madera County.
At a glance
EPA quarter 2026Q2
Hardness
Hard
179.5 PPM · 10.5 GPG
Compliance screen
Review needed
1 active health-based record
Lead 90th percentile
0.003 mg/L
20% of action level
Utility match
3 systems
Serves 66,560 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
179.5 PPM
Parts per million
179.5
mg/L as CaCO₃ equivalent
Grains per gallon
10.5
1 GPG ≈ 17.1 PPM
What this means at home
At 179.5 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
308
Nearest site
4.4 mi
Observation range
Feb 8, 2016–Aug 13, 2025
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 012S017E20H001M (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.
Madera median
180 PPM
About the same1 indexed ZIP readings · Range 179.5–179.5 PPM
California median
189 PPM
9 PPM lower678 indexed ZIP readings · Range 3.3–728.5 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)
0.003 mg/L
Reported Dec 31, 2025
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 0.003
EPA limit 0.015
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| LEAD AND COPPER RULE REVISIONSHealth-based | CA2010016 | Unaddressed | Oct 17, 2024 |
| LEAD AND COPPER RULE REVISIONS | CA2010016 | Unaddressed | Oct 17, 2024 |
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 Madera ZIP 93637 using 179.5 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
179.5 PPM is 1× 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 systemsDrinking water protection
LEAD AND COPPER RULE REVISIONS has a measured benchmark flag or active health-based SDWIS record in this profile.
A certified multi-stage RO system targets a broader range of dissolved contaminants at the kitchen tap.
Explore under-sink filtrationAffiliate 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 reports 1 active health-based violation among the associated community water systems. Review the affected utility's current notice and Consumer Confidence Report.
Nearby USGS observations produce an estimate of 179.5 PPM, or 10.5 grains per gallon, classified as hard. This is not a household tap measurement.
At 179.5 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.