Is Mission Viejo, CA Tap Water Safe to Drink?
Mission Viejo tap water meets federal Safe Drinking Water Act standards but 2 of 2 ZIP codes show detections above EPA health guidelines, primarily for lithium. A certified filter is recommended for households that want an additional layer of protection.
Where Does Mission Viejo Get Its Water?
Water in Mission Viejo, CA is provided by 3 public water systems: EL TORO WATER DISTRICT, MOULTON NIGUEL WATER DISTRICT and SANTA MARGARITA WATER DISTRICT.
How Is Mission Viejo Tap Water Treated?
Treated water is disinfected using free chlorine and calcium hypochlorite and chloramines and ozone. Treatment includes conventional treatment (coagulation, flocculation, and filtration) and direct filtration.
What's in Mission Viejo Tap Water?
The following contaminants were detected most frequently in Mission Viejo public water systems. 2 of 2 ZIP codes showed detections above EPA health guidelines.
| Contaminant | Peak detected | EPA guideline | ZIPs detected | Status |
|---|---|---|---|---|
| lithium | 45 µg/L | 10 µg/L | 2 ZIPs | Above guideline |
| PFTrDA | 0.007 µg/L | — | 0 ZIPs | Within guideline |
| PFBA | 0.005 µg/L | — | 0 ZIPs | Within guideline |
| 6:2 FTS | 0.005 µg/L | — | 0 ZIPs | Within guideline |
| 8:2 FTS | 0.005 µg/L | — | 0 ZIPs | Within guideline |
Health Risk Profile for Mission Viejo
Based on EPA monitoring data, 2 of 2 ZIP codes in Mission Viejo have recorded detections above EPA health guidelines. Sensitive populations such as infants, pregnant individuals, and those with weakened immune systems may benefit from an additional layer of protection such as a certified point-of-use filter.
Best Filters for PFAS Water Profile
PFAS compounds are detected in this water supply. A reverse osmosis (RO) system or an activated-carbon filter specifically certified under NSF/ANSI P473 is required for reliable PFAS reduction. Standard pitcher and faucet filters without P473 certification do not remove PFAS.
8-stage tankless RO system certified to NSF/ANSI 58, reduces 1,000+ contaminants including PFAS, lead, arsenic, fluoride, and nitrates.
NSF-certified dual-layer filtration reduces 70+ contaminants including PFAS, lead, chlorine, microplastics, and bacteria.
See recommendations matched to your exact address: choose your ZIP code below.
Frequently Asked Questions about Mission Viejo Tap Water
Is Mission Viejo tap water safe to drink?
Mission Viejo tap water meets Safe Drinking Water Act requirements but 2 of 2 ZIP codes show contaminant levels above EPA health-based guidelines. A certified point-of-use filter adds an extra layer of protection.
What contaminants are in Mission Viejo tap water?
The most commonly detected contaminants in Mission Viejo water systems include: lithium, PFTrDA, PFBA. See the ZIP-level reports for exact measurements and EPA guideline comparisons.
Where does Mission Viejo get its drinking water?
Mission Viejo receives water from 3 public water systems, including EL TORO WATER DISTRICT.
Do I need a water filter in Mission Viejo?
If your ZIP code is among those with detections above EPA health guidelines, choose a filter certified for the specific contaminants shown in your ZIP report. Reverse osmosis is generally the broadest option for PFAS, lithium, and many other dissolved contaminants.
How often is Mission Viejo tap water tested?
Public water systems in Mission Viejo are required by the EPA to test for regulated contaminants on schedules ranging from daily (for microbials and disinfectants) to annual or triennial (for many chemical contaminants). Results are published in annual Consumer Confidence Reports (CCRs). The data on this page reflects the most recent available EPA monitoring results, with the latest sample date of 2025-06-04.
Tap water reports by ZIP in Mission Viejo
- 92691 - El Toro Mobile Home Estates, Mission Viejo tap water report Higher concern
- 92692 - Mission Viejo CCD, Mission Viejo tap water report Higher concern
Water utilities serving Mission Viejo, CA
Service area boundaries are approximate and based on state filings or modeled estimates. Contact your utility to confirm exact service at a specific address.
- MOULTON NIGUEL WATER DISTRICTAction advised
- SANTA MARGARITA WATER DISTRICTAction advised
Also covers / overlaps with
- Mission Viejo CCD, CA · Township