Is Rosemead, CA tap water safe?

Data: U.S. EPA · How we read the data · How we check it

No federal limits exceeded in EPA data for San Gabriel Valley Water Company – El Monte. 2 PFAS were detected below the limits.

6 public water systems serve parts of Rosemead. The largest, San Gabriel Valley Water Company – El Monte, serves 240,000 people. Your water bill names your system.

Largest system

San Gabriel Valley Water Company – El Monte

240,000 people · Groundwater · EPA ID CA1910039

Buys treated water from Suburban Water Systems-San Jose, City of Whittier Water Dept., City of Pico Rivera Water Dept., Valley County Water District, City of Santa Fe Springs Water Dept., City of Arcadia, San Gabriel Valley Water Company – Montebello 2.

PFAS	Highest average	Limit	Status
PFOA Not detected	–	4 ppt	Not detected
PFOS Not detected	–	4 ppt	Not detected
PFHxS Not detected	–	10 ppt	Not detected
PFNA Not detected	–	10 ppt	Not detected
HFPO-DA (GenX) Not detected	–	10 ppt	Not 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 (Nov 2026, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 2

Full San Gabriel Valley Water Company – El Monte 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.

Rosemead homes and lead pipes

77%

of homes built before 1980 (California 56%, US 50%)

26%

built before 1950 (California 14%)

53%

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

Other water systems serving Rosemead

California American Water – San Marino
48,065 people · Purchased surface water · California · reported ZIPs here
Lithium above screening level
San Gabriel County Water District
40,154 people · Groundwater · California · reported ZIPs here
No PFAS above limits
Golden State Water Company – South San Gabriel
26,451 people · Purchased surface water · California · reported ZIPs here
Lithium above screening level
California American Water – Duarte
24,767 people · Groundwater · California · reported ZIPs here
PFOS detected
California American Water – Baldwin Hills
20,724 people · Purchased surface water · California · reported ZIPs here
Lithium above screening level

How nearby cities compare

City	Main water system	PFAS
San Gabriel 2 mi San Gabriel Valley Water Company – El Monte	San Gabriel Valley Water Company – El Monte	None above limits
Temple City 3 mi San Gabriel Valley Water Company – El Monte	San Gabriel Valley Water Company – El Monte	None above limits
El Monte 3 mi San Gabriel Valley Water Company – El Monte	San Gabriel Valley Water Company – El Monte	None above limits
Monterey Park 3 mi San Gabriel Valley Water Company – El Monte	San Gabriel Valley Water Company – El Monte	None above limits
Alhambra 3 mi City of Alhambra	City of Alhambra	None above limits
Montebello 4 mi San Gabriel Valley Water Company – El Monte	San Gabriel Valley Water Company – El Monte	None above limits

Rosemead ZIP codes (1)

91770

Questions

Is Rosemead tap water safe to drink?

San Gabriel Valley Water Company – El Monte had 2 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 Rosemead, CA?

6 public water systems serve parts of Rosemead. The largest is San Gabriel Valley Water Company – El Monte (240,000 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.

Does Rosemead tap water have PFAS?

San Gabriel Valley Water Company – El Monte had 2 PFAS detected at least once in EPA's 2023–2025 testing, all with averages below the federal limits.

Do Rosemead homes have lead pipes?

Census estimates put 77% of Rosemead 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. San Gabriel Valley Water Company – El Monte'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.