Excellent Water Quality
| Compound | Level | EPA MCL | Health Guideline | Status |
|---|---|---|---|---|
| PFOS | 26.0 ppt | 4 ppt | 4 ppt | Exceeded |
| PFHxS | 9.3 ppt | 10 ppt | 10 ppt | Below limit |
| PFOA | 8.6 ppt | 4 ppt | 4 ppt | Exceeded |
| PFPeA | 6.7 ppt | No standard | — | Unregulated |
| PFHxA | 6.1 ppt | No standard | 400 ppt | Unregulated |
| PFBS | 4.3 ppt | 2000 ppt | 100 ppt | Below limit |
| PFHpA | 3.6 ppt | No standard | — | Unregulated |
Water Quality Summary
Tap water quality in Modesto, California (95351) receives an overall grade of A (Excellent) with a score of 85 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is roughly in line with the California state average of 81. The area is served by 2 water systems providing water to approximately 218,797 people, using surface water and groundwater sources. Notably, 2 PFAS compounds exceed EPA limits — a significant concern given the persistent nature of these chemicals.
A score of 85/100 means the water supply in Modesto, CA meets or exceeds all EPA standards with minimal issues. Contaminant levels are well within safe limits, and the water system has maintained a strong compliance record. While no water supply is guaranteed perfect at the tap due to household plumbing, this is among the best-scoring areas in the country.
Common Questions
Based on EPA data, tap water in Modesto, California receives a grade of A (Excellent) with a score of 85/100. This indicates the water meets federal standards and has relatively few concerns. However, individual homes may still have localized issues such as lead from old plumbing.
ZIP code 95351 is served by 2 water systems using surface water, groundwater sources, providing water to approximately 218,797 people. Multiple source types mean your water may come from a blend of surface and underground sources.
No lead data is currently available for ZIP code 95351. This may mean lead testing results haven't been reported recently, or the serving water system uses monitoring waivers. You can request a free lead test kit from most water utilities or purchase a certified home testing kit.
Yes — 7 PFAS compounds were detected in water serving Modesto, California, and 2 exceed EPA maximum contaminant levels. PFAS are persistent chemicals linked to cancer, immune system effects, and developmental issues. A reverse osmosis or activated carbon filter certified for PFAS removal is recommended.
Water systems serving Modesto, California have received 1 violation in the last 5 years. Violations can range from paperwork issues (monitoring & reporting) to serious health-based violations where contaminant levels exceeded safe limits. Review the violation details above for specifics.
Based on detected contaminants (PFAS), residents in Modesto, California should consider: Reverse osmosis (RO) system — most effective for PFAS, lead, and other contaminants. Always look for filters with NSF/ANSI certification for the specific contaminants you want to remove.