Hardness
Very Hard
203 PPM · 11.9 GPG
Local water dashboard
Official source aggregationWater quality in Mountain Iron, MN 55751
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for St. Louis County.
No active health-based violation reported
- Primary matched system
- Mountain Iron
- Source water
- Groundwater
- County
- St. Louis County
- Profile updated
At a glance
What the current records say
EPA quarter 2026Q2
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 2,880 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
203 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
203
mg/L as CaCO₃ equivalent
Grains per gallon
11.9
1 GPG ≈ 17.1 PPM
What this means at home
At 203 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
10
Nearest site
49.6 mi
Observation range
May 12, 2016–Sep 20, 2024
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: CWO2-C Cromwell Near Nest 0000773066 (Well).USGS source documentation ↗
Regional context
Is 55751 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Mountain Iron median
203 PPM
About the same3 indexed ZIP readings · Range 203–203 PPM
Minnesota median
318 PPM
115 PPM lower319 indexed ZIP readings · Range 46.1–716 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 mg/L
Reported Dec 31, 2023
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
EPA limit 0.015
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 2
- Health-based
- 0
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Revised Total Coliform Rule | MN1690035 | Resolved | Apr 1, 2021through Apr 30, 2021 |
| Chlorine | MN1690035 | Resolved | Apr 1, 2021through May 1, 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
Your personalized water action plan
Matched to Mountain Iron ZIP 55751 using 203 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
High-Capacity Whole House Water Softener
203 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.
Nearby indexed reports
Compare ZIPs in Mountain Iron
Estimates can differ across a city because monitoring locations and associated systems differ.
Frequently asked
Water questions for Mountain Iron
Is tap water safe in Mountain Iron?+
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.
How hard is the water?+
Nearby USGS observations produce an estimate of 203 PPM, or 11.9 grains per gallon, classified as very hard. This is not a household tap measurement.
Do I need a water softener?+
At 203 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.