Water Quality in Saint Johns, AZ: 10 Violations — Grade C
Grade C · Score 66/100 · 1 water system · Updated 2026-05-03
Saint Johns's water has moderate compliance issues. Residents in affected areas should consider filtration.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Local water systems serving Saint Johns, AZ carry 10 EPA violations on record in the federal compliance database — documented events spanning categories from maximum contaminant level exceedances to monitoring requirements tracked by the national Safe Drinking Water program.
Water Quality by ZIP Code in Saint Johns
Water quality varies across Saint Johns's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 85936 | C | 66 | 10 | 0 | View report → |
Water Quality Overview
Saint Johns, Arizona receives a water quality grade of C with an overall score of 66 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 1 water system serving Saint Johns have accumulated 10 EPA violations (all monitoring/reporting type). These violations are tracked across 1 ZIP codes serving approximately 3,500 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Saint Johns's water systems have some violations that warrant attention. While the water may still be safe for most people, residents in affected ZIP codes should consider additional testing or filtration.
Lead Levels
Lead testing data for Saint Johns is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
With 41% of homes built before 1986, Saint Johns has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
Saint Johns is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Saint Johns
Saint Johns is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 3,500 people across 1 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 10 enforcement actions against water systems serving Saint Johns. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Saint Johns
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Saint Johns Water Systems
The following contaminants have been detected or caused violations across Saint Johns's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Revised Total Coliform Rule | Microbiological | N/A | 3 | 1 | No |
| Gross Beta | Radionuclides | 50 pCi/L | 3 | 1 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 2 | 1 | No |
| Surface Water Treatment Rule | Treatment Technique | N/A | 1 | 1 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving Saint Johns. Recent actions:
| Date | Action Type |
|---|---|
| 2024-01-24 | State Informal Action |
| 2024-01-24 | State Order Extension |
| 2023-06-01 | State Order Extension |
| 2023-02-15 | State Informal Action |
| 2023-02-10 | State Informal Action |
| 2023-02-10 | State Order Extension |
| 2022-11-25 | State Informal Action |
| 2022-11-25 | State Order Extension |
| 2022-02-04 | State Order Extension |
| 2022-02-03 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2024-01-24.
Saint Johns vs. Nearby Arizona Cities
How Saint Johns's water quality compares to similar cities in Arizona:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Saint Johns | C | 10 | 1 | 3,500 |
| Tubac | C | 21 | 5 | 3,431 |
| Lake Montezuma | C | 0 | 1 | 3,423 |
| Cornville | C | 11 | 4 | 3,374 |
Common Questions About Saint Johns Water
These are the most common questions residents search for about water quality in Saint Johns, Arizona:
Is Saint Johns water hard or soft? Water hardness varies by source. Saint Johns's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Saint Johns tap water? Saint Johns's water receives a grade of C (66/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Saint Johns? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Saint Johns vs. Arizona Average
Understanding how Saint Johns compares to the broader Arizona average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Saint Johns.
ZIP Codes in Saint Johns
Saint Johns spans 1 ZIP code. The ZIP with the lowest water quality score is 85936. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.