Hardness
Very Hard
245 PPM · 14.3 GPG
Local water dashboard
Official source aggregationWater quality in Nogales, AZ 85621
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Santa Cruz County.
3 active health-based violations
- Primary matched system
- Nogales City Of
- Source water
- Groundwater
- County
- Santa Cruz County
- Profile updated
At a glance
What the current records say
EPA quarter 2026Q2
Compliance screen
Review needed
3 active health-based records
Lead 90th percentile
0 mg/L
0% of action level
Utility match
5 systems
Serves 22,000 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
245 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
245
mg/L as CaCO₃ equivalent
Grains per gallon
14.3
1 GPG ≈ 17.1 PPM
What this means at home
At 245 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
27
Nearest site
36.3 mi
Observation range
Jan 11, 2016–Mar 31, 2026
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: SWALLOW SPRING (Spring).USGS source documentation ↗
Regional context
Is 85621 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Nogales median
245 PPM
About the same1 indexed ZIP readings · Range 245–245 PPM
Arizona median
241 PPM
About the same285 indexed ZIP readings · Range 66.4–1250 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 pass1 fail
Lead (PB90)
0 mg/L
Reported Dec 31, 2025
Copper (CU90)
1.4 mg/L
Reported Dec 31, 2004
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 1.4
EPA limit 1.3
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 113
- Health-based
- 7
- Active health-based
- 3
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Chlorine | AZ0412311 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Chlorine | AZ0412305 | Resolved | Nov 1, 2025through Nov 30, 2025 |
| Public Notice | AZ0412009 | Resolved | Oct 19, 2025through Jul 1, 2025 |
| Public Notice | AZ0412009 | Resolved | Oct 18, 2025through Jul 1, 2025 |
| Public Notice | AZ0412311 | Unaddressed | Oct 17, 2025 |
| Consumer Confidence Rule | AZ0412311 | Unaddressed | Oct 2, 2025 |
| Arsenic | AZ0412004 | Archived | Oct 1, 2025through Dec 31, 2025 |
| Chlorine | AZ0412311 | Archived | Oct 1, 2025through Oct 31, 2025 |
| Lead and Copper Rule | AZ0412311 | Unaddressed | Oct 1, 2025 |
| Lead and Copper Rule | AZ0412305 | Unaddressed | Oct 1, 2025 |
| Chlorine | AZ0412305 | Resolved | Oct 1, 2025through Oct 31, 2025 |
| Arsenic | AZ0412004 | Archived | Jul 1, 2025through Sep 30, 2025 |
| Nitrate | AZ0412004 | Resolved | Jul 1, 2025through Sep 30, 2025 |
| Chlorine | AZ0412004 | Resolved | Jul 1, 2025through Jul 31, 2025 |
| Chlorine | AZ0412311 | Archived | Jul 1, 2025through Jul 31, 2025 |
| Chlorine | AZ0412305 | Resolved | Jul 1, 2025through Jul 31, 2025 |
| Chlorine | AZ0412015 | Resolved | Jul 1, 2025through Jul 31, 2025 |
| Public Notice | AZ0412311 | Resolved | Jun 27, 2025through Jul 31, 2025 |
| Groundwater RuleHealth-based | AZ0412311 | Resolved | Apr 14, 2025through May 13, 2025 |
| Lead and Copper Rule | AZ0412311 | Resolved | Jan 1, 2025through Apr 22, 2025 |
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 Nogales ZIP 85621 using 245 PPM nearby hardness and 2 reported measurement benchmarks.
Scale protection
High-Capacity Whole House Water Softener
245 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
Under-Sink Reverse Osmosis System
Copper (90th percentile) 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
Water questions for Nogales
Is tap water safe in Nogales?+
EPA ECHO reports 3 active health-based violations among the associated community water systems. Review the affected utility's current notice and Consumer Confidence Report.
How hard is the water?+
Nearby USGS observations produce an estimate of 245 PPM, or 14.3 grains per gallon, classified as very hard. This is not a household tap measurement.
Do I need a water softener?+
At 245 PPM, a correctly sized whole-house softener can reduce scale and hard-water spotting. It does not replace contaminant filtration.