Tap Water Results

Is Rancho Cucamonga, 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 Cucamonga Valley Water District.

Cucamonga Valley Water District supplies Rancho Cucamonga (213,375 people).

Water system

Cucamonga Valley Water District

213,375 people · Surface water · EPA ID CA3610018

Buys treated water from San Gabriel Valley Water Company – Fontana, City of Upland, Ontario Municipal Utilities Company.

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 Cucamonga Valley 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.

Rancho Cucamonga homes and lead pipes

29%
of homes built before 1980 (California 56%, US 50%)
2%
built before 1950 (California 14%)
38%
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. Renting? Ask your landlord what the service line is made of, because it's their pipe to replace. How to check your own line.

Housing: Census American Community Survey 2020–2024 5-year estimates for Rancho Cucamonga city (tables B25034, B25003). Estimates for small places have a margin of error.

How nearby cities compare

CityMain water systemPFASLead (90th pct.)
Upland 5 mi
Cucamonga Valley Water District
Cucamonga Valley Water DistrictNone above limits0 ppb
Fontana 6 mi
San Gabriel Valley Water Company – Fontana
San Gabriel Valley Water Company – FontanaNone above limits0 ppb
Ontario 6 mi
Cucamonga Valley Water District
Cucamonga Valley Water DistrictNone above limits0 ppb
Montclair 8 mi
Monte Vista Water District
Monte Vista Water DistrictAbove limit0 ppb
Jurupa Valley 10 mi
Jurupa Community Services District
Jurupa Community Services DistrictNone above limits0 ppb
Rialto 10 mi
West Valley Water District
West Valley Water DistrictNone above limits0 ppb
Rancho Cucamonga ZIP codes (4)
  • 91701
  • 91730
  • 91737
  • 91739

Questions

Is Rancho Cucamonga tap water safe to drink?

Cucamonga Valley 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 Rancho Cucamonga, CA?

Cucamonga Valley Water District, which serves 213,375 people.

Does Rancho Cucamonga tap water have PFAS?

None detected above EPA's reporting limits. Cucamonga Valley 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 Rancho Cucamonga homes have lead pipes?

Census estimates put 29% of Rancho Cucamonga 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. Cucamonga Valley 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.