Hardness
Moderately Hard
68.8 PPM · 4 GPG
Local water dashboard
Official source aggregationWater quality in Frankfort, SD 57440
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Spink County.
No active health-based violation reported
- Primary matched system
- Spink Colony
- Source water
- Groundwater
- County
- Spink 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
0.001 mg/L
7% of action level
Utility match
3 systems
Serves 108 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
68.8 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
68.8
mg/L as CaCO₃ equivalent
Grains per gallon
4
1 GPG ≈ 17.1 PPM
What this means at home
At 68.8 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
1
Nearest site
74.5 mi
Observation range
May 1, 2024–May 1, 2024
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: 127N057W03AD (Britton BDM well 1) (Well).USGS source documentation ↗
Regional context
Is 57440 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Frankfort median
69 PPM
About the same1 indexed ZIP readings · Range 68.8–68.8 PPM
South Dakota median
516 PPM
447 PPM lower234 indexed ZIP readings · Range 20.5–1330 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)
0.001 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.
Lead (90th percentile)
Measured in mg/L
Local 0.001
EPA limit 0.015
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 5
- Health-based
- 1
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Revised Total Coliform RuleHealth-based | SD4602060 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Revised Total Coliform Rule | SD4602060 | Resolved | Oct 1, 2024through Oct 31, 2024 |
| Combined Uranium | SD4602059 | Resolved | Jan 1, 2022through Dec 31, 2022 |
| Gross Alpha, Excl. Radon and U | SD4602059 | Resolved | Jan 1, 2022through Dec 31, 2022 |
| Combined Radium (-226 and -228) | SD4602059 | Resolved | Jan 1, 2022through Dec 31, 2022 |
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 Frankfort ZIP 57440 using 68.8 PPM nearby hardness and 1 reported measurement benchmarks.
No urgent match
Start with an independent water test
This profile does not trigger a treatment recommendation. Test at the tap before investing in equipment.
Affiliate 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 Frankfort
Is tap water safe in Frankfort?+
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 68.8 PPM, or 4 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.