Hardness
Hard
126 PPM · 7.4 GPG
Local water dashboard
Official source aggregationWater quality in Hamilton, MT 59840
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Ravalli County.
1 reported benchmark flag
- Primary matched system
- Hamilton City Of
- Source water
- Groundwater
- County
- Ravalli 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
0.002 mg/L
13% of action level
Utility match
10 systems
Serves 5,660 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
126 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
126
mg/L as CaCO₃ equivalent
Grains per gallon
7.4
1 GPG ≈ 17.1 PPM
What this means at home
At 126 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
33
Nearest site
33.5 mi
Observation range
Mar 4, 2016–Jun 9, 2026
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: CHIEF JOSEPH PASS SNOW SITE, MT (Land).USGS source documentation ↗
Regional context
Is 59840 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Hamilton median
126 PPM
About the same1 indexed ZIP readings · Range 126–126 PPM
Montana median
122 PPM
About the same129 indexed ZIP readings · Range 0.2–799.5 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)
0.002 mg/L
Reported Dec 31, 2025
Copper (CU90)
7.11 mg/L
Reported Dec 31, 2010
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0.002
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 7.11
EPA limit 1.3
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 |
|---|---|---|---|
| Lead and Copper Rule | MT0003982 | Resolved | Dec 30, 2024through Mar 17, 2025 |
| Consumer Confidence Rule | MT0004533 | Resolved | Jul 1, 2024through Jul 31, 2024 |
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 Hamilton ZIP 59840 using 126 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
High-Capacity Whole House Water Softener
126 PPM is 1× 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
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 Hamilton
Is tap water safe in Hamilton?+
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 126 PPM, or 7.4 grains per gallon, classified as hard. This is not a household tap measurement.
Do I need a water softener?+
At 126 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.