Hardness
Very Hard
417 PPM · 24.4 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 Waukesha County.
At a glance
EPA quarter 2026Q2
Hardness
Very Hard
417 PPM · 24.4 GPG
Compliance screen
Review needed
1 active health-based record
Lead 90th percentile
0.0013 mg/L
8% of action level
Utility match
7 systems
Serves 410 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
417 PPM
Parts per million
417
mg/L as CaCO₃ equivalent
Grains per gallon
24.4
1 GPG ≈ 17.1 PPM
What this means at home
At 417 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
67
Nearest site
4.2 mi
Observation range
May 31, 2017–Aug 8, 2024
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 7N20E-18.1c (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.
Elm Grove median
417 PPM
About the same1 indexed ZIP readings · Range 417–417 PPM
Wisconsin median
288 PPM
129 PPM higher556 indexed ZIP readings · Range 41.3–467 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)
0.0013 mg/L
Reported Sep 30, 2024
Copper (CU90)
4.4 mg/L
Reported Sep 30, 2015
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Measured in mg/L
Local 0.0013
EPA limit 0.015
Measured in mg/L
Local 4.4
EPA limit 1.3
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| LEAD AND COPPER RULE REVISIONS | WI2680201 | Resolved | Jul 2, 2025through Nov 28, 2025 |
| LEAD AND COPPER RULE REVISIONS | WI2680862 | Unaddressed | Jul 2, 2025 |
| LEAD AND COPPER RULE REVISIONS | WI2680288 | Unaddressed | Jul 2, 2025 |
| Consumer Confidence Rule | WI2680862 | Resolved | Jul 1, 2025through Oct 2, 2025 |
| Consumer Confidence Rule | WI2680862 | Resolved | Jul 1, 2025through Oct 2, 2025 |
| Consumer Confidence Rule | WI2680288 | Resolved | Jul 1, 2025through Oct 2, 2025 |
| Consumer Confidence Rule | WI2680288 | Resolved | Jul 1, 2025through Oct 2, 2025 |
| Lead and Copper Rule | WI2680201 | Resolved | Jan 1, 2025through Jan 2, 2025 |
| Lead and Copper Rule | WI2682406 | Resolved | Jan 1, 2025through Dec 11, 2025 |
| Lead and Copper Rule | WI2680288 | Resolved | Jan 1, 2025through Jan 2, 2025 |
| LEAD AND COPPER RULE REVISIONS | WI2680201 | Resolved | Oct 17, 2024through Oct 18, 2024 |
| LEAD AND COPPER RULE REVISIONSHealth-based | WI2685370 | Resolved | Oct 17, 2024through Oct 17, 2024 |
| Public Notice | WI2685370 | Unaddressed | Oct 17, 2024 |
| Public Notice | WI2685370 | Unaddressed | Oct 17, 2024 |
| LEAD AND COPPER RULE REVISIONS | WI2685370 | Resolved | Oct 17, 2024through Oct 17, 2024 |
| LEAD AND COPPER RULE REVISIONS | WI2682406 | Resolved | Oct 17, 2024through Feb 27, 2025 |
| Public Notice | WI2682406 | Unaddressed | Oct 17, 2024 |
| Public Notice | WI2682406 | Unaddressed | Oct 17, 2024 |
| LEAD AND COPPER RULE REVISIONSHealth-based | WI2682406 | Unaddressed | Oct 17, 2024 |
| Groundwater RuleHealth-based | WI2682406 | Resolved | Jul 2, 2023through Aug 15, 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 Elm Grove ZIP 53122 using 417 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
417 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 systemsDrinking water protection
Copper (90th percentile), LEAD AND COPPER RULE REVISIONS have 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 417 PPM, or 24.4 grains per gallon, classified as very hard. This is not a household tap measurement.
At 417 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.