Water Quality in Potrero, CA: 40 Violations — Grade C
Grade C · Score 55/100 · 1 water system · Updated 2026-05-03
Potrero'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
Potrero, CA has 40 violations in the EPA compliance history — breakdown below.
Water Quality by ZIP Code in Potrero
Water quality varies across Potrero's 2 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 91963 | C | 55 | 20 | 16 | View report → |
| 91990 | C | 55 | 20 | 16 | View report → |
Violation Trend
EPA violations recorded for water systems serving Potrero.
Water Quality Overview
Potrero, California receives a water quality grade of C with an overall score of 55 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 1 water system serving Potrero have accumulated 40 EPA violations, including 32 health-based violations. These violations are tracked across 2 ZIP codes serving approximately 400 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Potrero'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 Potrero is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
Water Systems Serving Potrero
Potrero is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 400 people across 2 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 6 enforcement actions against water systems serving Potrero. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Potrero
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 Potrero Water Systems
The following contaminants have been detected or caused violations across Potrero's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Barium | Inorganic | 2 mg/L | 36 | 2 | Yes |
| Lead | Inorganic | 0.015 mg/L | 2 | 2 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 2 | 2 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Violation Trend Over Time
Year-by-year EPA violations recorded for water systems serving Potrero:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2021 | 4 | 4 |
| 2022 | 8 | 8 |
| 2023 | 6 | 6 |
| 2024 | 8 | 8 |
| 2025 | 4 | 4 |
Violation counts have remained stable over the observed period.
EPA Enforcement History
The EPA and state regulators have taken 3 enforcement actions against water systems serving Potrero. Recent actions:
| Date | Action Type |
|---|---|
| 2025-08-04 | State Filed Suit |
| 2024-08-05 | State Filed Suit |
| 2024-03-04 | State Filed Suit |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-08-04.
Potrero vs. Nearby California Cities
How Potrero's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Potrero | C | 40 | 1 | 400 |
| Dulzura | B | 0 | 1 | 400 |
| Penn Valley | B | 3 | 2 | 400 |
| Tecate | C | 0 | 1 | 400 |
Common Questions About Potrero Water
These are the most common questions residents search for about water quality in Potrero, California:
Is Potrero water hard or soft? Water hardness varies by source. Potrero's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Potrero tap water? Potrero's water receives a grade of C (55/100). There are 32 health-based violations — consider filtration.
What is the best water filter for Potrero? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Potrero vs. California Average
Understanding how Potrero compares to the broader California 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 Potrero.
ZIP Codes in Potrero
Potrero spans 2 ZIP codes. The ZIP with the lowest water quality score is 91963. 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.