Hardness
Moderately Hard
109 PPM · 6.4 GPG
Local water dashboard
Official source aggregationWater quality in Madill, OK 73446
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Marshall County.
2 reported benchmark flags
- Primary matched system
- Madill
- Source water
- Surface water
- County
- Marshall 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
0.0017 mg/L
11% of action level
Utility match
1 system
Serves 3,410 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
109 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
109
mg/L as CaCO₃ equivalent
Grains per gallon
6.4
1 GPG ≈ 17.1 PPM
What this means at home
At 109 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
38
Nearest site
10.8 mi
Observation range
Apr 4, 2016–May 20, 2026
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: Lk Texoma at Hwy 70 Bridge nr Little City, OK (Lake, Reservoir, Impoundment).USGS source documentation ↗
Regional context
Is 73446 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Madill median
109 PPM
About the same1 indexed ZIP readings · Range 109–109 PPM
Oklahoma median
226 PPM
117 PPM lower148 indexed ZIP readings · Range 7–610 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 pass2 fail
Lead (PB90)
0.0017 mg/L
Reported Dec 31, 2023
Copper (CU90)
Not available
No numerical 90th-percentile result
Numerical coverage
3 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0.0017
EPA limit 0.015
Total Haloacetic Acids (HAA5)
Measured in MG/L
Local 0.061
EPA limit 0.06
TTHM
Measured in MG/L
Local 0.096
EPA limit 0.08
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 56
- Health-based
- 30
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Chlorine | OK1010820 | Archived | Jan 1, 2026through Jan 31, 2026 |
| Revised Total Coliform Rule | OK1010820 | Archived | Jan 1, 2026through Jan 31, 2026 |
| Total Haloacetic Acids (HAA5) | OK1010820 | Resolved | Dec 30, 2025through Feb 4, 2026 |
| TTHM | OK1010820 | Resolved | Dec 30, 2025through Feb 4, 2026 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.061 MG/L · MCL 0.06 | OK1010820 | Archived | Oct 1, 2025through Dec 31, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.072 MG/L · MCL 0.06 | OK1010820 | Archived | Oct 1, 2025through Dec 31, 2025 |
| TTHMHealth-basedReported 0.096 MG/L · MCL 0.08 | OK1010820 | Archived | Oct 1, 2025through Dec 31, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.072 MG/L · MCL 0.06 | OK1010820 | Archived | Jul 1, 2025through Sep 30, 2025 |
| TTHMHealth-basedReported 0.084 MG/L · MCL 0.08 | OK1010820 | Archived | Jul 1, 2025through Sep 30, 2025 |
| TTHMHealth-basedReported 0.092 MG/L · MCL 0.08 | OK1010820 | Archived | Jul 1, 2025through Sep 30, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.066 MG/L · MCL 0.06 | OK1010820 | Archived | Jul 1, 2025through Sep 30, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.07 MG/L · MCL 0.06 | OK1010820 | Archived | Apr 1, 2025through Jun 30, 2025 |
| TTHMHealth-basedReported 0.093 MG/L · MCL 0.08 | OK1010820 | Archived | Apr 1, 2025through Jun 30, 2025 |
| TTHMHealth-basedReported 0.092 MG/L · MCL 0.08 | OK1010820 | Archived | Apr 1, 2025through Jun 30, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.069 MG/L · MCL 0.06 | OK1010820 | Archived | Apr 1, 2025through Jun 30, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.076 MG/L · MCL 0.06 | OK1010820 | Archived | Jan 1, 2025through Mar 31, 2025 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.069 MG/L · MCL 0.06 | OK1010820 | Archived | Jan 1, 2025through Mar 31, 2025 |
| TTHMHealth-basedReported 0.1 MG/L · MCL 0.08 | OK1010820 | Archived | Jan 1, 2025through Mar 31, 2025 |
| TTHMHealth-basedReported 0.1 MG/L · MCL 0.08 | OK1010820 | Archived | Jan 1, 2025through Mar 31, 2025 |
| TTHMHealth-basedReported 0.1 MG/L · MCL 0.08 | OK1010820 | Archived | Oct 1, 2024through Dec 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 Madill ZIP 73446 using 109 PPM nearby hardness and 3 reported measurement benchmarks.
Drinking water protection
Under-Sink Reverse Osmosis System
Total Haloacetic Acids (HAA5), TTHM have 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 Madill
Is tap water safe in Madill?+
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 109 PPM, or 6.4 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.