Is Lake Forest, CA tap water safe?
Data: U.S. EPA · How we read the data · How we check it
Summary
No federal limits exceeded in EPA data for Irvine Ranch Water District. 2 PFAS were detected below the limits.
2 public water systems serve parts of Lake Forest. The largest, Irvine Ranch Water District, serves 450,323 people. Your water bill names your system.
Largest system
Irvine Ranch Water District
450,323 people · Surface water · EPA ID CA3010092
Buys treated water from City of Newport Beach, Trabuco Canyon Water District, Joint Regional Water Supply System, Laguna Beach County Water District, City of Orange, East Orange County Water District – Wz, South Coast Water District, Santa Margarita Water District, Mesa Water District, City of Tustin, El Toro Water District, Metropolitan Water District of SO. Cal..
| PFAS | Highest average | Limit |
|---|---|---|
| PFOA Not detected | – | 4 ppt |
| PFOS Not detected | – | 4 ppt |
| PFHxS Not detected | – | 10 ppt |
| PFNA Not detected | – | 10 ppt |
| HFPO-DA (GenX) Not detected | – | 10 ppt |
ppt = parts per trillion. "Highest average" is the highest average at any of the system's entry points, the way EPA compares results with the limits.
Lead: 0 ppb at the 90th percentile (Dec 2025, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0
Across California, 129 of 691 water systems EPA tested had PFAS above a 2024 federal limit, and 26 systems were above the lead action level in results from the last five years. California results.
Lake Forest homes and lead pipes
Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. How to check your own line.
Housing: Census American Community Survey 2020–2024 5-year estimates for Lake Forest city (tables B25034, B25003). Estimates for small places have a margin of error.
Other water systems serving Lake Forest
How nearby cities compare
| City | PFAS | Lead (90th pct.) |
|---|---|---|
| Mission Viejo 3 mi Moulton Niguel Water District | None above limits | 0 ppb |
| Laguna Hills 5 mi Moulton Niguel Water District | None above limits | 0 ppb |
| Rancho Santa Margarita 5 mi Santa Margarita Water District | None above limits | 0 ppb |
| Irvine 6 mi Irvine Ranch Water District | None above limits | 0 ppb |
| Aliso Viejo 6 mi Moulton Niguel Water District | None above limits | 0 ppb |
| Laguna Niguel 9 mi Moulton Niguel Water District | None above limits | 0 ppb |
Lake Forest ZIP codes (2)
- 92610
- 92630
Questions
Is Lake Forest tap water safe to drink?
Irvine Ranch Water District has had no health-based violations since 2016. Utility data can't show lead from your own pipes: if your home was built before 1986, test your tap. Your utility's annual Consumer Confidence Report is the official summary.
Who supplies water in Lake Forest, CA?
2 public water systems serve parts of Lake Forest. The largest is Irvine Ranch Water District (450,323 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.
Does Lake Forest tap water have PFAS?
Irvine Ranch Water District had 2 PFAS detected at least once in EPA's 2023–2025 testing, all with averages below the federal limits.
Do Lake Forest homes have lead pipes?
Census estimates put 38% of Lake Forest homes as built before 1980 (California: 56%). Lead service lines and lead solder were allowed until 1986, so older homes are more likely to have them. Irvine Ranch Water District's service line inventory says what your line is made of. The only way to know for your home is to check the line where it enters the house and test your tap.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.