Hardness
Very Hard
417 PPM · 24.4 GPG
Local water dashboard
Official source aggregationWater quality in Mukwonago, WI 53149
A 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.
1 active health-based violation
- Primary matched system
- Mukwonago Waterworks
- Source water
- Groundwater
- County
- Waukesha County
- Profile updated
At a glance
What the current records say
EPA quarter 2026Q2
Compliance screen
Review needed
1 active health-based record
Lead 90th percentile
0.0033 mg/L
22% of action level
Utility match
3 systems
Serves 8,190 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
417 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
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
71
Nearest site
7.5 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: 4N19E-1.7c (Well).USGS source documentation ↗
Regional context
Is 53149 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Mukwonago 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
Contaminant snapshot
Available numerical results from associated SDWIS community water systems, compared with the applicable action level or federal MCL. Federal measured-value coverage is incomplete.
1 pass
Lead (PB90)
0.0033 mg/L
Reported Sep 30, 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.
Lead (90th percentile)
Measured in mg/L
Local 0.0033
EPA limit 0.015
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 90
- Health-based
- 2
- Active health-based
- 1
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Public Notice | WI2680246 | Unaddressed | Dec 20, 2025 |
| Groundwater RuleHealth-based | WI2680246 | Unaddressed | Dec 20, 2025 |
| Di(2-ethylhexyl) phthalate | WI2680246 | Archived | Oct 1, 2025through Dec 31, 2025 |
| Consumer Confidence Rule | WI2680246 | Unaddressed | Jul 1, 2025 |
| Consumer Confidence Rule | WI2680246 | Unaddressed | Jul 1, 2025 |
| Lead and Copper Rule | WI2680246 | Unaddressed | Jan 1, 2025 |
| Lead and Copper Rule | WI2680624 | Resolved | Jun 1, 2024through Sep 23, 2025 |
| Lead and Copper Rule | WI2680246 | Resolved | Jan 1, 2023through Jun 25, 2024 |
| Radium-226 | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| Radium-228 | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| CHLOROBENZENE | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| DICHLOROMETHANE | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| Ethylbenzene | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| Tetrachloroethylene | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| Trichloroethylene | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| Carbon tetrachloride | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| 1,1-Dichloroethylene | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| p-Dichlorobenzene | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| o-Dichlorobenzene | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
| Xylenes, Total | WI2680246 | Resolved | Oct 1, 2022through Dec 31, 2022 |
No reported violation does not prove that every contaminant was tested or absent; SDWIS measured values are incomplete and lag state records.
Solutions matcher
Your personalized water action plan
Matched to Mukwonago ZIP 53149 using 417 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
High-Capacity Whole House Water Softener
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
Under-Sink Reverse Osmosis System
Groundwater Rule 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
Water questions for Mukwonago
Is tap water safe in Mukwonago?+
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.
How hard is the water?+
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.
Do I need a water softener?+
At 417 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.