Is Pomona, CA tap water safe?
Data: U.S. EPA · How we read the data · How we check it
Summary
City of Pomona Water Dept., the largest system here, had PFAS above the 2024 federal limits (PFOA, PFOS) in EPA's 2023–2025 testing.
Is it an emergency? No: PFAS limits are about years of exposure, not a glass of water, and nothing in EPA's data calls for you to stop drinking the water today. If your utility issues a boil-water or do-not-drink notice, follow it.
4 public water systems serve parts of Pomona. The largest, City of Pomona Water Dept., serves 151,713 people, and 3 systems here had PFAS above a federal limit. Your water bill names your system.
Largest system
City of Pomona Water Dept.
151,713 people · Surface water · EPA ID CA1910126
Buys treated water from Three Valleys Municipal Water District, Metropolitan Water District of SO. Cal..
| PFAS | Highest average | Limit |
|---|---|---|
| PFOA Above limit | 6.45 ppt | 4 ppt |
| PFOS Above limit | 14.5 ppt | 4 ppt |
| PFHxS Detected, below limit | 7.8 ppt | 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.
For context: the PFOA average is higher than at 92% of the California systems EPA tested and the PFOS average is higher than at 92% of the California systems EPA tested.
Lead: 2.1 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.
Pomona homes and lead pipes
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 Pomona city (tables B25034, B25003). Estimates for small places have a margin of error.
Other water systems serving Pomona
- Monte Vista Water District56,390 people · Purchased surface water · California · reported ZIPs herePFOS above limitAlso: PFHxS detected
- Golden State Water Company – Claremont39,776 people · Purchased surface water · California · reported ZIPs herePFOA above limitAlso: PFOS above limit · PFHxS detected
- Calif State Polytechnical Univ – Pomona Water System2,668 people · Surface water · California · reported ZIPs hereTotal trihalomethanes (TTHM) violationsAlso: PFHxS detected
How nearby cities compare
| City | PFAS | Lead (90th pct.) |
|---|---|---|
| Montclair 4 mi Monte Vista Water District | Above limit | 0 ppb |
| La Verne 4 mi Walnut Valley Water District | None above limits | 0 ppb |
| San Dimas 4 mi Golden State Water Company – San Dimas | Above limit | 2.1 ppb |
| Diamond Bar 5 mi Walnut Valley Water District | None above limits | 0 ppb |
| Walnut 6 mi Suburban Water Systems-San Jose | None above limits | 0 ppb |
| Upland 7 mi Cucamonga Valley Water District | None above limits | 0 ppb |
Pomona ZIP codes (3)
- 91766
- 91767
- 91768
Questions
Is Pomona tap water safe to drink?
City of Pomona Water Dept. has had no health-based violations since 2016, and EPA testing found PFAS above the 2024 federal limits, which it must meet by 2029. 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 Pomona, CA?
4 public water systems serve parts of Pomona. The largest is City of Pomona Water Dept. (151,713 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.
Does Pomona tap water have PFAS?
Yes. EPA's 2023–2025 testing found entry-point averages above the 2024 federal limits for PFOA and PFOS at City of Pomona Water Dept.. Systems have until 2029 to meet them.
Do Pomona homes have lead pipes?
Census estimates put 66% of Pomona 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. City of Pomona Water Dept.'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.