Hardness
Hard
164 PPM · 9.6 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 Cascade County.
At a glance
EPA quarter 2026Q2
Hardness
Hard
164 PPM · 9.6 GPG
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
0 mg/L
0% of action level
Utility match
3 systems
Serves 1,233 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
164 PPM
Parts per million
164
mg/L as CaCO₃ equivalent
Grains per gallon
9.6
1 GPG ≈ 17.1 PPM
What this means at home
At 164 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
6
Nearest site
53.1 mi
Observation range
May 26, 2022–Sep 18, 2024
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: Sheep Cr ab Moose Cr, nr White Sulphur Springs, MT (Stream).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.
Black Eagle median
164 PPM
About the same1 indexed ZIP readings · Range 164–164 PPM
Montana median
122 PPM
42 PPM higher129 indexed ZIP readings · Range 0.2–799.5 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, 2026
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 RuleHealth-based | MT0000526 | Resolved | Aug 4, 2023through May 8, 2024 |
| Consumer Confidence Rule | MT0000526 | Resolved | Jul 1, 2023through Jul 21, 2023 |
| E. COLI | MT0000526 | Resolved | Jun 21, 2023through Oct 10, 2024 |
| Arsenic | MT0002806 | Resolved | Apr 1, 2023through Jun 14, 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 Black Eagle ZIP 59414 using 164 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
164 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 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 164 PPM, or 9.6 grains per gallon, classified as hard. This is not a household tap measurement.
At 164 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.