Costa Mesa, CA Water Quality Report
Is Costa Mesa tap water safe? See PFAS and lead contamination levels for Costa Mesa, California. Compare to EPA limits and get filter recommendations.
Quick Answers
Is Costa Mesa, CA tap water safe to drink? Costa Mesa, CA tap water meets most federal EPA limits, but PFAS compounds have been detected at an average of 6.5 ppt across 2 compounds. A certified pitcher filter or reverse osmosis system is recommended for sensitive populations.
What contaminants are in Costa Mesa, CA water? Top PFAS compounds detected in Costa Mesa water: PFBA (7.9 ppt), PFPeA (3.8 ppt). See the full table for all monitored contaminants and comparison to EPA limits.
What filter should I use in Costa Mesa, CA? For Costa Mesa, CA households, reverse osmosis removes 90%+ of PFAS, lead, and arsenic. Pitcher and faucet filters certified to NSF-53 for PFAS (ZeroWater, PUR PLUS) work for smaller households. Skip standard Brita filters for PFAS removal.
Costa Mesa, CA Water Quality Summary
EPA testing has detected PFAS "forever chemicals" in Costa Mesa, CA drinking water. Recent monitoring found a peak level of 7.9 ppt across 1 water system, representing an average of 6.5 ppt across 2 detected compounds. These levels come from individual EPA UCMR 5 water samples (2023-2025). The EPA's 4 ppt limit for PFOA and PFOS is enforced on a running annual average, so a sample above it shows real exposure but is not by itself a violation.
Contamination Level: LOW – Low contamination – PFAS detected but at lower levels; monitoring continues.
Top Detected Compounds
- PFBA: 7.9 ppt (exceeds EPA 4 ppt limit for PFOA/PFOS)
- PFPeA: 3.8 ppt
Lead in Costa Mesa, CA Water
EPA Lead and Copper Rule testing has recorded 14 lead samples for Costa Mesa water systems, with a 90th-percentile high of 0 mg/L (within the EPA 0.015 mg/L action level). There is no safe level of lead for children; if your home was built before 1986, a certified NSF/ANSI 53 lead-removal filter is recommended.
EPA Violations in Costa Mesa, CA
Costa Mesa public water systems have 35 health-based EPA Safe Drinking Water Act violations on record, including Surface Water Treatment Rule, Iron, Manganese. Health-based violations mean a contaminant exceeded its federal limit or required treatment was not applied.
About the Data
Source: EPA UCMR5 (Unregulated Contaminant Monitoring Rule 5), the 2023-2025 national testing program spanning about 10,000 public water systems – the broadest PFAS survey ever run in the US. Costa Mesa, CA serves a population of roughly 113,408.
ZIP Codes Served
What Costa Mesa, California Residents Should Do
- Enter your exact ZIP code at knowyourexposure.com for address-level data
- Request the latest Consumer Confidence Report (CCR) from your California utility – it is free and updated annually
- Choose a filter certified for PFAS: NSF/ANSI 58 reverse osmosis (94-99% removal) or an NSF-53 pitcher
- High-exposure households (pregnancy, infants, immunocompromised) should also consider a PFAS home test kit