Hardness
Hard
179 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 Fresno County.
At a glance
EPA quarter 2026Q2
Hardness
Hard
179 PPM · 10.5 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 9,306 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
179 PPM
Parts per million
179
mg/L as CaCO₃ equivalent
Grains per gallon
10.5
1 GPG ≈ 17.1 PPM
What this means at home
At 179 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
17
Nearest site
47.5 mi
Observation range
Sep 29, 2016–Mar 2, 2023
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: SALINAS R NR BRADLEY CA (Stream).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.
Huron median
179 PPM
About the same1 indexed ZIP readings · Range 179–179 PPM
California median
189 PPM
10 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 mg/L
Reported Dec 31, 2025
Copper (CU90)
Not available
No numerical 90th-percentile result
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Measured in mg/L
Local 0
EPA limit 0.015
Measured in MG/L
Local 0.16
EPA limit 0.08
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Surface Water Treatment RuleHealth-based | CA1010044 | Archived | Mar 1, 2026through Mar 31, 2026 |
| Surface Water Treatment RuleHealth-based | CA1010044 | Archived | Feb 1, 2026through Feb 28, 2026 |
| TTHMHealth-basedReported 0.16 MG/L · MCL 0.08 | CA1010044 | Archived | Jul 1, 2021through Sep 30, 2021 |
| TTHMHealth-basedReported 0.14 MG/L · MCL 0.08 | CA1010044 | Archived | Apr 1, 2021through Jun 30, 2021 |
| TTHMHealth-basedReported 0.138 MG/L · MCL 0.08 | CA1010044 | Archived | Jan 1, 2021through Mar 31, 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 Huron ZIP 93234 using 179 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
179 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
TTHM 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 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 179 PPM, or 10.5 grains per gallon, classified as hard. This is not a household tap measurement.
At 179 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.