Tap Water Results

Is San Juan Capistrano, 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 Moulton Niguel Water District.

3 public water systems serve parts of San Juan Capistrano. The largest, Moulton Niguel Water District, serves 168,315 people. Your water bill names your system.

Largest system

Moulton Niguel Water District

168,315 people · Purchased surface water · EPA ID CA3010073

Buys treated water from Santa Margarita Water District, South Coast Water District, Irvine Ranch Water District, Joint Regional Water Supply System, Metropolitan Water District of SO. Cal., El Toro Water District.

PFASHighest averageLimitStatus
PFOA
Not detected
–4 pptNot detected
PFOS
Not detected
–4 pptNot detected
PFHxS
Not detected
–10 pptNot detected
PFNA
Not detected
–10 pptNot detected
HFPO-DA (GenX)
Not detected
–10 pptNot detected

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 2024, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0

Full Moulton Niguel Water District results

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.

San Juan Capistrano homes and lead pipes

53%
of homes built before 1980 (California 56%, US 50%)
2%
built before 1950 (California 14%)
19%
of households rent (California 44%)

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 San Juan Capistrano city (tables B25034, B25003). Estimates for small places have a margin of error.

Other water systems serving San Juan Capistrano

How nearby cities compare

CityMain water systemPFASLead (90th pct.)
Dana Point 3 mi
Moulton Niguel Water District
Moulton Niguel Water DistrictNone above limits0 ppb
Laguna Niguel 3 mi
Moulton Niguel Water District
Moulton Niguel Water DistrictNone above limits0 ppb
San Clemente 4 mi
Santa Margarita Water District
Santa Margarita Water DistrictNone above limits0 ppb
Laguna Hills 7 mi
Moulton Niguel Water District
Moulton Niguel Water DistrictNone above limits0 ppb
Aliso Viejo 7 mi
Moulton Niguel Water District
Moulton Niguel Water DistrictNone above limits0 ppb
Mission Viejo 7 mi
Moulton Niguel Water District
Moulton Niguel Water DistrictNone above limits0 ppb
San Juan Capistrano ZIP codes (1)
  • 92675

Questions

Is San Juan Capistrano tap water safe to drink?

Moulton Niguel 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 San Juan Capistrano, CA?

3 public water systems serve parts of San Juan Capistrano. The largest is Moulton Niguel Water District (168,315 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.

Does San Juan Capistrano tap water have PFAS?

None detected above EPA's reporting limits. Moulton Niguel Water District had no PFAS detected in EPA's 2023–2025 testing. "Not detected" means below the reporting limit (about 2 to 20 ppt), not proven zero.

Do San Juan Capistrano homes have lead pipes?

Census estimates put 53% of San Juan Capistrano 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. Moulton Niguel 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.