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WaterSafeCheck

Potrero, CA Tap Water Quality

Water safety reports for all 2 ZIP codes in Potrero, California

Average Score

55/100

Health Violations

32

ZIP Codes

2

High Lead Risk

0

of 2 ZIP codes

C

About Tap Water in Potrero, CA

Water quality in Potrero, CA is currently rated with a moderate C grade (average score: 55/100 across 2 ZIP codes). This rating indicates that while the water provided by Twin Lakes Resort is treated and regulated, there have been notable compliance issues or contaminant detections recently. Residents should stay informed about the specific challenges affecting their local supply.

The accumulation of 32 health-based violations over the past 5 years highlights systemic challenges within Potrero's water infrastructure. When violations occur, it means that drinking water tests revealed contaminant levels exceeding safe limits, triggering mandatory corrective actions by California State Water Resources Control Board. The city relies on ground water, which may require significant treatment upgrades to address these recurring issues.

Fortunately, the modeled risk for widespread lead exposure in Potrero's municipal water is relatively low compared to national averages. However, because lead typically enters drinking water through the corrosion of older, individual home plumbing rather than the main supply lines, residents in homes built before 1986 should still exercise caution by running the tap before use.

Health-Based Contaminant Violations in Potrero

EPA records indicate that the following contaminants have exceeded Safe Drinking Water Act Maximum Contaminant Levels (MCLs) in Potrero water systems over the past 5 years.

Barium

Note: The presence of a past violation does not necessarily mean current water is unsafe. Utilities are required to take corrective action. Review your Consumer Confidence Report for the latest status.

Water Quality by ZIP Code — Potrero, CA

Click any ZIP code for the full water quality report

C
91963

Potrero, CA

Score: 55/10016 violations
C
91990

Potrero, CA

Score: 55/10016 violations

Frequently Asked Questions — Potrero Water Quality

Is tap water safe to drink in Potrero, CA?+
Tap water in Potrero has a grade of C, indicating compliance concerns in recent years. Families with young children or pregnant women should consider using a certified NSF/ANSI 53 water filter for drinking and cooking.
What is the water quality score for Potrero?+
The average water quality score across 2 ZIP codes in Potrero, CA is 55/100. Scores are derived from EPA violation history, lead levels, enforcement actions, and infrastructure risk indicators. Individual ZIP codes may vary — search your specific ZIP above for a personalized report.
Does Potrero have lead in its tap water?+
Lead risk ratings in Potrero are relatively low based on EPA monitoring data. However, lead in home plumbing is a separate concern — if your home was built before 1986, individual tap testing is recommended.
How do I get the water quality report for Potrero?+
Each ZIP code in Potrero has a full water quality report on this site — click any ZIP code below. You can also get the annual Consumer Confidence Report (CCR) from your local water utility. The CCR is required to be published every year by July 1 and contains actual contaminant measurements and violation history.
Where does Potrero's tap water come from?+
Tap water in Potrero, CA primarily comes from ground water. Groundwater systems pump water from underground aquifers, which is naturally filtered through soil and rock but can still contain naturally occurring contaminants.

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