Hardness
Moderately Hard
71.6 PPM · 4.2 GPG
Local water dashboard
Official source aggregationWater quality in Copper Harbor, MI 49918
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Keweenaw County.
1 reported benchmark flag
- Primary matched system
- Grant Township - Copper Harbor
- Source water
- Groundwater
- County
- Keweenaw 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
7.8e-4 mg/L
5% of action level
Utility match
1 system
Serves 200 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
71.6 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
71.6
mg/L as CaCO₃ equivalent
Grains per gallon
4.2
1 GPG ≈ 17.1 PPM
What this means at home
At 71.6 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
8
Nearest site
46.8 mi
Observation range
May 16, 2016–Oct 18, 2016
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: STE-51-024 (Spring).USGS source documentation ↗
Regional context
Is 49918 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Copper Harbor median
72 PPM
About the same1 indexed ZIP readings · Range 71.6–71.6 PPM
Michigan median
283 PPM
211 PPM lower504 indexed ZIP readings · Range 41.3–459.5 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 pass1 fail
Lead (PB90)
7.8e-4 mg/L
Reported Dec 31, 2023
Copper (CU90)
1.48 mg/L
Reported Dec 31, 2020
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 7.8e-4
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 1.48
EPA limit 1.3
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 4
- Health-based
- 1
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Lead and Copper RuleHealth-based | MI0001630 | Resolved | Jan 1, 2024through Jun 30, 2024 |
| Chlorine | MI0001630 | Resolved | Jul 1, 2023through Sep 30, 2023 |
| Total Haloacetic Acids (HAA5) | MI0001630 | Archived | Jan 1, 2023through Dec 31, 2025 |
| TTHM | MI0001630 | 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
Your personalized water action plan
Matched to Copper Harbor ZIP 49918 using 71.6 PPM nearby hardness and 2 reported measurement benchmarks.
Drinking water protection
Under-Sink Reverse Osmosis System
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.
Frequently asked
Water questions for Copper Harbor
Is tap water safe in Copper Harbor?+
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 71.6 PPM, or 4.2 grains per gallon, classified as moderately hard. This is not a household tap measurement.
Do I need a water softener?+
There is no high-hardness trigger in this profile. Confirm with a tap test before buying equipment.