Water Quality in 85621 — Nogales, AZ
EPA data for NOGALES CITY OF
Data source: U.S. Environmental Protection Agency (EPA) SDWIS Last verified: March 16, 2026
Your Water System
ZIP code 85621 in Nogales, Arizona is served by NOGALES CITY OF (EPA ID: AZ0412004). This system provides water to approximately 22,000 people from groundwater sources.
There are 5 community water systems serving this area.
Lead & Copper in Your Water
No Lead & Copper Rule sampling data available for systems serving this ZIP code.
Violation Summary
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| July 1, 2025 | Revised Total Coliform Rule | Monitoring | Unresolved |
| July 1, 2025 | Revised Total Coliform Rule | Monitoring | Unresolved |
| June 27, 2025 | Lead and Copper Rule | Monitoring | Resolved |
| April 14, 2025 | Contaminant 0700 | Health-based | Resolved |
| January 1, 2025 | Stage 1 DBP Rule | Monitoring | Resolved |
| December 20, 2024 | Lead and Copper Rule | Monitoring | Resolved |
| December 20, 2024 | Lead and Copper Rule | Monitoring | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Monitoring | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Health-based | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Monitoring | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Health-based | Unresolved |
| October 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Resolved |
| October 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Resolved |
| October 1, 2024 | Total Trihalomethanes (TTHM) | Monitoring | Resolved |
| October 1, 2024 | Total Trihalomethanes (TTHM) | Monitoring | Resolved |
| October 1, 2024 | Barium | Monitoring | Resolved |
| October 1, 2024 | PFOA | Monitoring | Unresolved |
| October 1, 2024 | PFOA | Monitoring | Unresolved |
| October 1, 2024 | PFOA | Monitoring | Resolved |
| October 1, 2024 | PFNA | Monitoring | Unresolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for water systems serving this ZIP code:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Barium | Inorganic | 17 | No |
| Revised Total Coliform Rule | Microbiological | 13 | No |
| Lead | Inorganic | 10 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 9 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 9 | No |
| Lead and Copper Rule | Treatment Technique | 9 | No |
| Stage 1 DBP Rule | Treatment Technique | 8 | No |
| PFOA | PFAS | 7 | No |
| PFNA | PFAS | 7 | No |
| Monochloroacetic Acid | Disinfection Byproducts | 7 | No |
| Dichloroacetic Acid | Disinfection Byproducts | 7 | No |
| Bromodichloromethane | Disinfection Byproducts | 7 | No |
| Dibromochloromethane | Disinfection Byproducts | 7 | No |
| Bromoform | Disinfection Byproducts | 7 | No |
| Chlorodibromomethane | Disinfection Byproducts | 7 | No |
Need help with your water quality?
Call to get connected with a local professional in your area.
Call (855) 384-4856This is a free service. You will be connected with an independent service provider.
Water Systems Serving This Area
| System Name | EPA ID | Population | Source |
|---|---|---|---|
| NOGALES CITY OF | AZ0412004 | 22,000 | Groundwater |
| VALLE VERDE WATER COMPANY - EAST | AZ0412009 | 2,331 | Groundwater |
| TOWN & COUNTRY - PRESTON | AZ0412311 | 430 | Groundwater |
| THE GRAND ACRES | AZ0412305 | 153 | Groundwater |
| KINO RANCH 2 | AZ0412015 | 109 | Groundwater |
What You Can Do
- Request your water system’s Consumer Confidence Report (CCR) — Your utility is required to publish this annually
- Consider a home water test — Independent testing can reveal issues in your specific plumbing
- Install a certified water filter — NSF-certified filters can address specific contaminants
- Contact your water provider — Ask about current treatment and any ongoing remediation
Need help with water testing or filtration?
Call to get connected with a local professional in your area.
Call (855) 384-4856This is a free service. You will be connected with an independent service provider.
Other Water Quality Reports in Arizona
- 85001 (Phoenix) — 248 violations
- 85117 (Apache Junction) — 263 violations
- 85122 (Casa Grande) — 52 violations
- 85123 (Arizona City) — 94 violations
- 85127 (Chandler Heights) — 6 violations
- 85128 (Coolidge) — 101 violations
- 85131 (Eloy) — 139 violations
- 85132 (Florence) — 109 violations
- 85135 (Hayden) — 91 violations
- 85137 (Kearny) — 82 violations
- 85138 (Maricopa) — 428 violations
- 85140 (San Tan Valley) — 90 violations
- 85141 (Picacho) — 88 violations
- 85142 (Queen Creek) — 70 violations
- 85145 (Red Rock) — 43 violations
- 85172 (Stanfield) — 92 violations
- 85173 (Superior) — 11 violations
- 85201 (Mesa) — 38 violations
- 85224 (Chandler) — 259 violations
- 85233 (Gilbert) — 364 violations
Nearby Water Quality Reports
- 85635 (Sierra Vista) — 41 mi — 431 violations
- 85701 (Tucson) — 58 mi — 214 violations
- 85607 (Douglas) — 83 mi — 22 violations
- 85145 (Red Rock) — 86 mi — 43 violations
- 85141 (Picacho) — 94 mi — 88 violations
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for NOGALES CITY OF (AZ0412004) on EPA.gov.
Frequently Asked Questions
Is the tap water in 85621 safe to drink?
Nogales’s water system has recorded 5 health-based violations in the past 5 years. While the system is required to treat water to meet federal standards, you may want to consider additional precautions such as a certified water filter.
Where does 85621’s water come from?
The primary water source for this area is groundwater. NOGALES CITY OF serves approximately 22,000 people.
How can I get my water tested?
Contact your local water utility for a free water quality report, or hire a certified lab for independent home water testing. The EPA recommends testing annually if you use a private well.
Does 85621 have lead in the water?
No Lead and Copper Rule sampling data is currently available in EPA records for water systems serving ZIP code 85621. If you are concerned about lead, contact your water utility or have your tap water independently tested.
What is the radon risk in 85621?
Radon zone data is not available for ZIP code 85621. The EPA recommends testing all homes for radon regardless of location, as radon levels can vary significantly even within the same neighborhood.