Hardness
Very Hard
290 PPM · 17 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 Whiteside County.
At a glance
EPA quarter 2026Q2
Hardness
Very Hard
290 PPM · 17 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 537 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
290 PPM
Parts per million
290
mg/L as CaCO₃ equivalent
Grains per gallon
17
1 GPG ≈ 17.1 PPM
What this means at home
At 290 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
23
Nearest site
25.3 mi
Observation range
May 22, 2017–Jun 11, 2020
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 081N05E09CAD 1997NAWQA (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.
Lyndon median
290 PPM
About the same1 indexed ZIP readings · Range 290–290 PPM
Illinois median
285 PPM
5 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 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
EPA limit 0.015
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Revised Total Coliform Rule | IL1950300 | Resolved | Aug 1, 2025through Aug 31, 2025 |
| Chlorine | IL1950300 | Resolved | Aug 1, 2025through Aug 31, 2025 |
| LEAD AND COPPER RULE REVISIONS | IL1950300 | Resolved | Jul 2, 2025through Dec 10, 2025 |
| Nitrate | IL1950300 | Resolved | Jul 1, 2023through Sep 30, 2023 |
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 Lyndon ZIP 61261 using 290 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
290 PPM is 2× 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 systemsAffiliate 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 290 PPM, or 17 grains per gallon, classified as very hard. This is not a household tap measurement.
At 290 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.