Hardness
Very Hard
394 PPM · 23 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 Winnebago County.
At a glance
EPA quarter 2026Q2
Hardness
Very Hard
394 PPM · 23 GPG
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
0.0073 mg/L
49% of action level
Utility match
6 systems
Serves 147,051 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
394 PPM
Parts per million
394
mg/L as CaCO₃ equivalent
Grains per gallon
23
1 GPG ≈ 17.1 PPM
What this means at home
At 394 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
75
Nearest site
7.1 mi
Observation range
May 30, 2017–Aug 8, 2023
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 44N 3E-34.2a1 (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.
Rockford median
394 PPM
About the same8 indexed ZIP readings · Range 373.5–396 PPM
Illinois median
285 PPM
109 PPM higher1065 indexed ZIP readings · Range 115–408 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)
0.0073 mg/L
Reported Jun 30, 2026
Copper (CU90)
1.48 mg/L
Reported Dec 31, 1992
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Measured in mg/L
Local 0.0073
EPA limit 0.015
Measured in mg/L
Local 1.48
EPA limit 1.3
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Revised Total Coliform Rule | IL2015345 | Archived | Mar 1, 2026through Mar 31, 2026 |
| Chlorine | IL2015345 | Archived | Mar 1, 2026through Mar 31, 2026 |
| Lead and Copper Rule | IL2015425 | Unaddressed | Oct 1, 2025 |
| LEAD AND COPPER RULE REVISIONS | IL2015100 | Unaddressed | Jul 2, 2025 |
| LEAD AND COPPER RULE REVISIONS | IL2015100 | Resolved | Oct 17, 2024through Jul 16, 2025 |
| LEAD AND COPPER RULE REVISIONSHealth-based | IL2015100 | Resolved | Oct 17, 2024through Jul 16, 2025 |
| Total Haloacetic Acids (HAA5) | IL2010300 | Resolved | Oct 1, 2024through Dec 31, 2024 |
| Consumer Confidence Rule | IL2015425 | Resolved | Jul 1, 2024through Jul 15, 2024 |
| Public Notice | IL2015345 | Resolved | Feb 9, 2024through Apr 24, 2024 |
| Public Notice | IL2015345 | Resolved | Feb 9, 2024through Apr 24, 2024 |
| Nitrate | IL2015100 | Resolved | Jan 1, 2024through Dec 31, 2024 |
| Nitrate | IL2015100 | Resolved | Jan 1, 2024through Dec 31, 2024 |
| Consumer Confidence Rule | IL2015100 | Resolved | Jul 1, 2023through Jun 25, 2024 |
| cis-1,2-Dichloroethylene | IL2010300 | Resolved | Jan 1, 2023through Dec 31, 2023 |
| Dinoseb | IL2010300 | Archived | Jan 1, 2023through Dec 31, 2025 |
| Chlordane | IL2010300 | Archived | Jan 1, 2023through Dec 31, 2025 |
| Chlordane | IL2010300 | Archived | Jan 1, 2023through Dec 31, 2025 |
| 2,4-D | IL2010300 | Archived | Jan 1, 2023through Dec 31, 2025 |
| 2,4,5-TP | IL2010300 | Archived | Jan 1, 2023through Dec 31, 2025 |
| Pentachlorophenol | IL2010300 | Archived | Jan 1, 2023through Dec 31, 2025 |
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 Rockford ZIP 61108 using 394 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
394 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) 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.
Nearby indexed reports
Estimates can differ across a city because monitoring locations and associated systems differ.
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 394 PPM, or 23 grains per gallon, classified as very hard. This is not a household tap measurement.
At 394 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.