Hardness
Very Hard
181 PPM · 10.6 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 Robertson County.
At a glance
EPA quarter 2026Q2
Hardness
Very Hard
181 PPM · 10.6 GPG
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
3.0e-4 mg/L
2% of action level
Utility match
1 system
Serves 9,162 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
181 PPM
Parts per million
181
mg/L as CaCO₃ equivalent
Grains per gallon
10.6
1 GPG ≈ 17.1 PPM
What this means at home
At 181 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
19
Nearest site
13 mi
Observation range
Apr 12, 2022–Jul 24, 2025
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: Rb:M-001 (Well).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.
Greenbrier median
181 PPM
About the same1 indexed ZIP readings · Range 181–181 PPM
Tennessee median
50 PPM
131 PPM higher323 indexed ZIP readings · Range 4.5–247 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)
3.0e-4 mg/L
Reported Dec 31, 2025
Copper (CU90)
Not available
No numerical 90th-percentile result
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Measured in mg/L
Local 3.0e-4
EPA limit 0.015
Measured in MG/L
Local 0.0648
EPA limit 0.06
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Consumer Confidence Rule | TN0000271 | Unaddressed | Jul 1, 2025 |
| Consumer Confidence Rule | TN0000271 | Unaddressed | Jul 1, 2024 |
| TTHM | TN0000271 | Resolved | Jan 1, 2023through Mar 31, 2023 |
| Total Haloacetic Acids (HAA5) | TN0000271 | Resolved | Jan 1, 2023through Mar 31, 2023 |
| Consumer Confidence Rule | TN0000271 | Resolved | Jul 1, 2022through Jul 19, 2022 |
| Total Haloacetic Acids (HAA5)Health-basedReported 0.0648 MG/L · MCL 0.06 | TN0000271 | Resolved | Jul 1, 2022through Sep 30, 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
Matched to Greenbrier ZIP 37073 using 181 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
181 PPM is 2× 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
Total Haloacetic Acids (HAA5) 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
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 181 PPM, or 10.6 grains per gallon, classified as very hard. This is not a household tap measurement.
At 181 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.