Hardness
Very Hard
286 PPM · 16.7 GPG
Local water dashboard
Official source aggregationWater quality in Mercedes, TX 78570
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Hidalgo County.
No active health-based violation reported
- Primary matched system
- City Of Mercedes
- Source water
- Surface water
- County
- Hidalgo 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
0.0037 mg/L
25% of action level
Utility match
1 system
Serves 16,258 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
286 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
286
mg/L as CaCO₃ equivalent
Grains per gallon
16.7
1 GPG ≈ 17.1 PPM
What this means at home
At 286 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
34.9 mi
Observation range
Feb 17, 2016–Apr 14, 2026
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: Rio Grande nr Brownsville, TX (Stream).USGS source documentation ↗
Regional context
Is 78570 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Mercedes median
286 PPM
About the same1 indexed ZIP readings · Range 286–286 PPM
Texas median
111 PPM
175 PPM higher1019 indexed ZIP readings · Range 5.4–500.5 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 pass
Lead (PB90)
0.0037 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 0.0037
EPA limit 0.015
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 7
- Health-based
- 1
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Lead and Copper Rule | TX1080007 | Resolved | Dec 30, 2025through Feb 24, 2026 |
| Public Notice | TX1080007 | Resolved | May 1, 2025through Oct 2, 2025 |
| LEAD AND COPPER RULE REVISIONSHealth-based | TX1080007 | Resolved | Oct 17, 2024through Oct 3, 2025 |
| LEAD AND COPPER RULE REVISIONS | TX1080007 | Resolved | Oct 17, 2024through Oct 3, 2025 |
| Public Notice | TX1080007 | Unaddressed | Jul 13, 2013 |
| Public Notice | TX1080007 | Addressed | Apr 15, 2011 |
| Public Notice | TX1080007 | Addressed | Jan 10, 2011 |
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 Mercedes ZIP 78570 using 286 PPM nearby hardness and 1 reported measurement benchmarks.
Scale protection
High-Capacity Whole House Water Softener
286 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 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
Water questions for Mercedes
Is tap water safe in Mercedes?+
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 286 PPM, or 16.7 grains per gallon, classified as very hard. This is not a household tap measurement.
Do I need a water softener?+
At 286 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.