Water Quality in Casa Grande, AZ: 72 Violations — Grade B
Grade B · Score 82/100 · 5 water systems · Updated 2026-05-03
Casa Grande's water is mostly safe. Minor violations exist but are primarily monitoring-related.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Available EPA records for Casa Grande, AZ: 72 water compliance violations tied to local public water systems.
Water Quality Map: Casa Grande, AZ
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Casa Grande
Water quality varies across Casa Grande's 8 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 85122 | B | 82 | 9 | 1 | View report → |
| 85130 | B | 82 | 9 | 1 | View report → |
| 85193 | B | 82 | 9 | 1 | View report → |
| 85194 | B | 82 | 9 | 1 | View report → |
| 85222 | B | 82 | 9 | 1 | View report → |
| 85230 | B | 82 | 9 | 1 | View report → |
| 85293 | B | 82 | 9 | 1 | View report → |
| 85294 | B | 82 | 9 | 1 | View report → |
Water Quality Overview
Casa Grande, Arizona receives a water quality grade of B with an overall score of 82 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Casa Grande have accumulated 72 EPA violations, including 8 health-based violations. These violations are tracked across 8 ZIP codes serving approximately 140,682 people.
What Grade B Means
A grade of B indicates good compliance with EPA drinking water standards. While not perfect, Casa Grande's water systems meet the vast majority of federal requirements. Minor violations may exist but typically relate to monitoring or reporting rather than health-based standards.
Lead Levels
The average 90th percentile lead level across Casa Grande water systems is 0.0010 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
Radon Risk
Casa Grande is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Casa Grande
Casa Grande is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 140,682 people across 8 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 80 enforcement actions against water systems serving Casa Grande. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Casa Grande
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 Casa Grande Water Systems
The following contaminants have been detected or caused violations across Casa Grande's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Lead | Inorganic | 0.015 mg/L | 16 | 8 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 16 | 8 | No |
| Stage 2 DBP Rule | Treatment Technique | N/A | 16 | 8 | Yes |
| Barium | Inorganic | 2 mg/L | 8 | 8 | No |
| Total Coliform | Microbiological | N/A | 8 | 8 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 8 | 8 | 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 Casa Grande. Recent actions:
| Date | Action Type |
|---|---|
| 2025-09-30 | State Informal Enforcement |
| 2025-09-17 | State Informal Action |
| 2025-09-17 | State Informal Enforcement |
| 2025-09-10 | State Order Extension |
| 2025-07-31 | State Informal Action |
| 2025-07-31 | State Order Extension |
| 2025-04-17 | State Informal Action |
| 2025-04-17 | State Order Extension |
| 2024-12-26 | State Informal Action |
| 2024-11-18 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-09-30.
Casa Grande vs. Nearby Arizona Cities
How Casa Grande's water quality compares to similar cities in Arizona:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Casa Grande | B | 72 | 5 | 140,682 |
| Yuma | C | 360 | 5 | 152,412 |
| Waddell | C | 0 | 1 | 127,718 |
| Tempe | B | 192 | 4 | 166,887 |
Water Quality by ZIP Code in Casa Grande
Water quality varies across Casa Grande's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 85122 | 82 | B | 9 | 1 |
| 85130 | 82 | B | 9 | 1 |
| 85193 | 82 | B | 9 | 1 |
| 85194 | 82 | B | 9 | 1 |
| 85222 | 82 | B | 9 | 1 |
| 85230 | 82 | B | 9 | 1 |
| 85293 | 82 | B | 9 | 1 |
| 85294 | 82 | B | 9 | 1 |
Common Questions About Casa Grande Water
These are the most common questions residents search for about water quality in Casa Grande, Arizona:
Is Casa Grande water hard or soft? Water hardness varies by source. Casa Grande's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Casa Grande tap water? Casa Grande's water receives a grade of B (82/100). There are 8 health-based violations — consider filtration.
What is the best water filter for Casa Grande? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Casa Grande vs. Arizona Average
Understanding how Casa Grande 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 Casa Grande.
ZIP Codes in Casa Grande
Casa Grande spans 8 ZIP codes. The ZIP with the lowest water quality score is 85122. 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.
Frequently Asked Questions
Your Water is Safe — Here's How to Keep It That Way
Grade B is excellent news. Here's what proactive homeowners do to maintain water quality:
Annual Water Testing
EPA recommends annual testing even with clean water. Home test kits: $20-$50. Catches changes before they become problems.
Maintenance Filtration
A basic carbon filter removes chlorine taste and catches emerging contaminants like PFAS that aren't yet fully regulated.
Plumbing Check
Even safe city water picks up lead from home pipes. If your home was built before 1986, a one-time pipe inspection is recommended.