California PFAS results from EPA's final data
Report published Nov 14, 2026 · EPA UCMR 5 final data file of Oct 15, 2026 (samples collected 2023–2025) · Method · National results →
129 California water systems serving 8.9 million people had PFAS above a 2024 federal limit in EPA's final round of nationwide PFAS testing: 19% of the 691 California systems tested, compared with 11% nationally.
Highest PFOA or PFOS averages in California
- Running Springs Water District Running Springs · PFOS131 ppt
- Liberty Utilities – Bellflower-Norwalk Norwalk · PFOS55 ppt
- Montebello Land & Water Company Montebello · PFOS46.5 ppt
- City of Sacramento Main Sacramento · PFOS38.9 ppt
- City of Downey Water Dept. Downey · PFOS38 ppt
- City of Clovis Clovis · PFOS36 ppt
- Tract 349 Mutual Water Company Bell Gardens · PFOS34.7 ppt
- Bellflower Municipal Water System Bellflower · PFOS30.5 ppt
- City of Pico Rivera Water Dept. Pico Rivera · PFOS28.5 ppt
- Pico Water District Pico Rivera · PFOS25.5 ppt
- City of Norwalk Water Dept. Norwalk · PFOS25 ppt
- Maywood Mutual Water Company #3 Maywood · PFOS24.8 ppt
- City of South Gate Water Dept. South Gate · PFOS24 ppt
- City of Pleasanton Pleasanton · PFOS24 ppt
- Tract 180 Mutual Water Company Bell Gardens · PFOS23 ppt
Chart data as a table
| System | ppt |
|---|---|
| Running Springs Water District · Running Springs · PFOS | 131 |
| Liberty Utilities – Bellflower-Norwalk · Norwalk · PFOS | 55 |
| Montebello Land & Water Company · Montebello · PFOS | 46.5 |
| City of Sacramento Main · Sacramento · PFOS | 38.9 |
| City of Downey Water Dept. · Downey · PFOS | 38 |
| City of Clovis · Clovis · PFOS | 36 |
| Tract 349 Mutual Water Company · Bell Gardens · PFOS | 34.7 |
| Bellflower Municipal Water System · Bellflower · PFOS | 30.5 |
| City of Pico Rivera Water Dept. · Pico Rivera · PFOS | 28.5 |
| Pico Water District · Pico Rivera · PFOS | 25.5 |
| City of Norwalk Water Dept. · Norwalk · PFOS | 25 |
| Maywood Mutual Water Company #3 · Maywood · PFOS | 24.8 |
| City of South Gate Water Dept. · South Gate · PFOS | 24 |
| City of Pleasanton · Pleasanton · PFOS | 24 |
| Tract 180 Mutual Water Company · Bell Gardens · PFOS | 23 |
Largest systems above a limit
| # | System | People served |
|---|---|---|
| 1 | City of Fresno Fresno Above: PFOA, PFOS, PFHxS, Hazard Index | 545,970 |
| 2 | City of Sacramento Main Sacramento Above: PFOA, PFOS, PFHxS, Hazard Index | 527,979 |
| 3 | City of Anaheim Anaheim Above: PFOA, PFOS | 350,254 |
| 4 | City of Santa Ana Santa Ana Above: PFOA, PFOS | 316,184 |
| 5 | Santa Clarita Valley Water Agency Santa Clarita Above: PFOA, PFOS | 292,014 |
| 6 | California Water Service – Bakersfield Bakersfield Above: PFOA, PFOS | 268,129 |
| 7 | City of Modesto Modesto Above: PFOA, PFOS | 218,915 |
| 8 | City of Huntington Beach Huntington Beach Above: PFOS | 201,000 |
| 9 | City of Stockton Stockton Above: PFOS | 192,702 |
| 10 | City of Glendale Water Dept. Glendale Above: PFOA, PFOS | 192,212 |
All 129 California systems above a limit
Every California community water system whose UCMR 5 results averaged above a 2024 federal PFAS limit, largest first. Systems that were not tested are not listed: not tested is not the same as not detected.
Full list: 129 systems, largest first
| System | People served |
|---|---|
| City of Fresno Fresno Above: PFOA, PFOS, PFHxS, Hazard Index | 545,970 |
| City of Sacramento Main Sacramento Above: PFOA, PFOS, PFHxS, Hazard Index | 527,979 |
| City of Anaheim Anaheim Above: PFOA, PFOS | 350,254 |
| City of Santa Ana Santa Ana Above: PFOA, PFOS | 316,184 |
| Santa Clarita Valley Water Agency Santa Clarita Above: PFOA, PFOS | 292,014 |
| California Water Service – Bakersfield Bakersfield Above: PFOA, PFOS | 268,129 |
| City of Modesto Modesto Above: PFOA, PFOS | 218,915 |
| City of Huntington Beach Huntington Beach Above: PFOS | 201,000 |
| City of Stockton Stockton Above: PFOS | 192,702 |
| City of Glendale Water Dept. Glendale Above: PFOA, PFOS | 192,212 |
| SCWA – Laguna/Vineyard Vineyard Above: PFOA, PFOS | 188,417 |
| Ontario Municipal Utilities Company Ontario Above: PFOA | 185,010 |
| Sweetwater Authority Chula Vista Above: PFOA | 184,915 |
| City of Garden Grove Garden Grove Above: PFOA, PFOS | 174,226 |
| City of Bakersfield Bakersfield Above: PFOS | 171,108 |
| California Water Service – Visalia Visalia Above: PFOS | 153,522 |
| City of Pomona Water Dept. Pomona Above: PFOA, PFOS | 151,713 |
| Rancho California Water District Temecula Above: PFOA, PFOS | 146,147 |
| California Water Service – East Los Angeles Montebello Above: PFOS | 142,140 |
| City of Fullerton Fullerton Above: PFOA, PFOS | 140,054 |
| City of Clovis Clovis Above: PFOA, PFOS | 133,118 |
| California American Water – Monterey Monterey Above: PFOA, PFOS | 128,928 |
| City of Orange Orange Above: PFOA, PFOS | 120,770 |
| Golden State Water Company – West Orange County Cypress Above: PFOA, PFOS | 114,693 |
| City of Downey Water Dept. Downey Above: PFOA, PFOS | 110,556 |
| California Water Service – Chico Chico Above: PFOS, PFHxS, Hazard Index | 110,473 |
| East Valley Water District Highland Above: PFOA, PFOS | 108,600 |
| Hesperia Water District Hesperia Above: PFOA, PFOS | 101,836 |
| City of Vacaville Vacaville Above: PFOS | 99,650 |
| City of Merced Merced Above: PFOS | 96,073 |
| City of Westminster Westminster Above: PFOS | 93,591 |
| City of Compton Water Dept. Compton Above: PFOS | 90,986 |
| City of Redding Redding Above: PFOA, PFOS | 90,254 |
| City of South Gate Water Dept. South Gate Above: PFOA, PFOS | 88,544 |
| City of Manteca Manteca Above: PFOA, PFHxS | 84,928 |
| City of Buena Park Buena Park Above: PFOS | 82,667 |
| Redlands City Municipal Utility District – Water Division Redlands Above: PFOS | 78,025 |
| City of Pleasanton Pleasanton Above: PFOA, PFOS, PFHxS, Hazard Index | 76,689 |
| Liberty Utilities – Bellflower-Norwalk Norwalk Above: PFOA, PFOS | 72,472 |
| City of Lodi Lodi Above: PFOS | 67,093 |
| City of Lynwood Water Dept. Lynwood Above: PFOA, PFOS | 66,967 |
| Suburban Water Systems-Whittier Whittier Above: PFOA, PFOS | 66,565 |
| City of Lakewood Water Dept. Lakewood Above: PFOS | 66,356 |
| City of Watsonville Watsonville Above: PFOA, PFOS | 65,231 |
| City of Porterville Porterville Above: PFOA, PFOS | 63,487 |
| California Water Service – Livermore Pleasanton Above: PFOS | 60,414 |
| City of Gilroy Gilroy Above: PFOA | 59,426 |
| Suburban Water Systems-la Mirada La Mirada Above: PFOA, PFOS | 57,240 |
| Golden State Water Company – San Dimas San Dimas Above: PFOS | 56,564 |
| Monte Vista Water District Montclair Above: PFOS | 56,390 |
| Golden State Water Company – Bell, Bell Gardens Bell Gardens Above: PFOS | 55,050 |
| California American Water – Suburban Rosemont Rancho Cordova Above: PFOA, PFOS | 54,893 |
| City of Ceres Ceres Above: PFOA, PFOS | 54,513 |
| City of Arcadia Arcadia Above: PFOS | 54,236 |
| Golden State Water Company – Placentia/Yorba Linda Yorba Linda Above: PFOA, PFOS | 50,804 |
| California American Water – Parkway Elk Grove Above: PFOS | 50,646 |
| Golden State Water Company – Artesia Artesia Above: PFOS | 50,415 |
| City of Whittier Water Dept. Whittier Above: PFOS | 49,954 |
| City of Colton Colton Above: PFOS | 46,525 |
| Bellflower – Somerset Mutual Water Company Bellflower Above: PFOS | 46,300 |
| City of Adelanto Adelanto Above: PFOS | 39,930 |
| Golden State Water Company – Claremont San Dimas Above: PFOA, PFOS | 39,776 |
| City of Pico Rivera Water Dept. Pico Rivera Above: PFOA, PFOS | 39,451 |
| City of Lathrop Lathrop Above: PFOS | 38,596 |
| City of Monrovia Water Dept. Monrovia Above: PFOS | 37,931 |
| Lakeside Water District Lakeside Above: PFOS | 35,500 |
| Atascadero Mutual Water Company Atascadero Above: PFOA, PFOS | 33,307 |
| Camrosa Water District Camarillo Above: PFOS | 32,700 |
| City of Paso Robles Water Division Paso Robles Above: PFOA | 31,176 |
| South Tahoe Public Utility District – Main South Lake Tahoe Above: PFOA, PFOS | 30,089 |
| City of Atwater Atwater Above: PFOA, PFOS, PFHxS, Hazard Index | 29,479 |
| Crescenta Valley County Water District Glendale Above: PFOA | 28,162 |
| California Water Service – North Garden Rosedale Above: PFOS | 27,634 |
| Golden State Water Company – South Arcadia Arcadia Above: PFOA, PFOS | 27,430 |
| Montebello Land & Water Company Montebello Above: PFOA, PFOS | 26,554 |
| City of Sanger Sanger Above: PFOA, PFOS | 26,357 |
| Sunnyslope County Water District Hollister Above: PFOA | 25,486 |
| City of Norco Norco Above: PFOA, PFOS | 25,068 |
| Orchard Dale Water District Whittier Above: PFOA, PFOS | 25,000 |
| Liberty Utilities – Lynwood Lynwood Above: PFOA, PFOS | 24,649 |
| Valley of the Moon Water District El Verano Above: PFOA | 23,140 |
| Pico Water District Pico Rivera Above: PFOA, PFOS | 22,051 |
| City of Norwalk Water Dept. Norwalk Above: PFOA, PFOS | 20,283 |
| City of Santa Fe Springs Water Dept. Santa Fe Springs Above: PFOA, PFOS | 19,219 |
| Riverside Highland Water Company Riverside Above: PFOA, PFOS | 19,053 |
| City of Arroyo Grande Utilities Division Arroyo Grande Above: PFOS | 17,963 |
| Western Municipal Water District – Murrieta Division Murrieta Above: PFOA, PFOS | 17,837 |
| Pinedale County Water District Fresno Above: PFOA, PFOS | 16,736 |
| City of Ukiah Ukiah Above: PFOS | 16,067 |
| City of Ripon Ripon Above: PFOA, PFOS | 15,753 |
| City of Huntington Park Water Dept. Huntington Park Above: PFOA, PFOS | 15,437 |
| South Montebello Irrigation District Montebello Above: PFOA, PFOS | 15,021 |
| Pala North Water System Pala Above: PFOA | 14,280 |
| Tract 180 Mutual Water Company Bell Gardens Above: PFOA, PFOS | 14,000 |
| Big Bear City Community Services District Big Bear City Above: PFOS, PFHxS, Hazard Index | 12,738 |
| City of Lindsay Lindsay Above: PFOA, PFOS | 12,659 |
| Crestline Village County Water District – Division 10 Crestline Above: PFHxS, Hazard Index | 11,650 |
| City of Bell Gardens Bell Gardens Above: PFOA, PFOS | 11,413 |
| City of Sonoma Sonoma Above: PFOA | 10,619 |
| SCWA – Arden Park Vista Arden-Arcade Above: PFOS | 10,068 |
| Golden Hills Community Services District Tehachapi Above: PFOA, PFOS | 9,857 |
| Tract 349 Mutual Water Company Bell Gardens Above: PFOA, PFOS | 8,700 |
| Florin County Water District Florin Above: PFOA, PFOS | 7,831 |
| City of Gridley Gridley Above: PFOS, Hazard Index | 7,269 |
| Los Osos Community Services District Los Osos Above: PFOA, PFOS | 7,086 |
| Lake Arrowhead Community Services District Lake Arrowhead Above: PFOA, PFOS | 7,038 |
| Rincon Northern Water System Valley Center Above: PFOS | 7,003 |
| Peter Pitchess Honor Rancho Detention Center Water System Castaic Above: PFOA, PFOS | 7,000 |
| Nuevo Water Company Nuevo Above: PFOA | 6,733 |
| Rubio Canon Land & Water Association Altadena Above: PFOA, PFOS | 6,646 |
| Helendale Community Service District Helendale Above: PFOA, PFOS | 6,347 |
| Maywood Mutual Water Company #3 Maywood Above: PFOA, PFOS | 6,059 |
| Bellflower Municipal Water System Bellflower Above: PFOA, PFOS | 6,032 |
| California American Water – Meadowbrook Sacramento Above: PFOS | 5,723 |
| La Habra Heights County Water District La Habra Above: PFOA, PFOS | 5,682 |
| Pleasant Valley Mutual Water Company Camarillo Above: PFOA, PFOS | 5,306 |
| Yosemite Spring Park Utilities Company Coarsegold Above: PFOA, PFOS | 5,300 |
| Running Springs Water District Running Springs Above: PFOA, PFOS, PFHxS, Hazard Index | 5,268 |
| Suburban Water Systems – Sativa Compton Above: PFOS | 4,372 |
| California American Water – Arden Sacramento Above: PFOA | 4,178 |
| Planada Community Services District Planada Above: PFOS | 4,164 |
| City of Wheatland Wheatland Above: PFOS | 4,124 |
| Weaverville Community Services District Douglas City Above: PFOS | 3,975 |
| Maywood Mutual Water Company #1 Maywood Above: PFOS | 3,851 |
| San Joaquin County – Mokelumne Acres Woodbridge Above: PFOA, PFOS | 3,802 |
| City of Commerce Water Dept. Montebello Above: PFOA | 3,598 |
| California State University Fresno Water System Fresno Above: PFOA | 1,500 |
| Atascadero State Hospital Water System Atascadero Above: PFOS, PFHxS, Hazard Index | 1,100 |
| California State Fair Water System Sacramento Above: PFOS | 80 |
The same list, with PFOA and PFOS averages, is in the data download.
Which limits were exceeded
| PFAS | Federal limit | Systems above it |
|---|---|---|
| PFOA 6.4 million people | 4 ppt | 84 |
| PFOS 8.2 million people | 4 ppt | 114 |
| PFHxS 1.4 million people | 10 ppt | 10 |
| PFNA | 10 ppt | 0 |
| GenX (HFPO-DA) | 10 ppt | 0 |
| Hazard Index 1.3 million people | 1 | 10 |
"–" in the table above means not detected. A system can be above more than one limit. EPA proposed in May 2026 to rescind the PFHxS, PFNA, GenX and Hazard Index limits. That proposal is not final.
California has its own PFAS rules. Response levels: PFOA 10, PFOS 40, PFHxS 10, PFBS 5,000, PFHxA 10,000 ppt. Above RL, ordered systems must remove source, treat, or notify. PFOA/PFOS/PFHxS/PFHxA levels issued 2025-10-29. Details. This report compares results with the federal limits only.
Data and how to cite it
- Download every California water system as CSV (PFOA and PFOS averages, systems above a limit, lead, violations).
- EPA's source file: UCMR 5 occurrence data.
Suggested citation:
Tap Water Results, "California PFAS results from EPA's final UCMR 5 data" (published Nov 14, 2026, EPA data file of Oct 15, 2026). https://tapwaterresults.com/pfas/california/
You're welcome to quote and republish these figures with a link back. Questions from reporters: see contact.
Method
For each system we average each entry point's UCMR 5 results (non-detects count as zero, complete sets of samples only) and compare the highest entry-point average with the 2024 federal limit, using EPA's rounding. This is how EPA compares UCMR 5 results to the limits in its own data summary, and our national counts match EPA's published table within 2% (how we check). Results are monitoring data from 2023–2025, not compliance determinations, and treatment installed since then is not reflected. Full method.
Questions
How many California water systems have PFAS above the limit?
129 of the 691 California community water systems EPA tested in 2023–2025 (19%) had at least one entry-point average above a 2024 federal PFAS limit. They serve 8.9 million people. Nationally the share is 11%.
Are these systems violating the law?
Not yet. Systems have until 2029 to meet the 2024 limits, and EPA has proposed moving the PFOA and PFOS deadline to 2031 and rescinding the other limits. EPA's UCMR 5 results are monitoring data and do not determine compliance.
Which systems were tested?
EPA's UCMR 5 tested every community water system serving more than 3,300 people and a representative sample of smaller ones. Systems that were not tested have no federal result, which is not the same as having no PFAS.
All California water systems → · National results → · PFAS results for every state →
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.