County · California
Merced County, California: drinking water records
This overview covers 19 ZIP codes and 24 community water systems in Merced County. It also stands in for 2 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| City of Los Banos CA2410005 | 47,419 | 780 | 0 | 1 | 0 ppb |
| City of Livingston CA2410004 | 14,894 | 480 | 0 | 2 | 0 ppb |
| Winton Water & Sanitary Dist CA2410010 | 9,745 | 180 | 0 | 1 | 0 ppb |
| City of Dos Palos CA2410002 | 7,452 | 120 | 0 | 27 | 0 ppb |
| City of Gustine CA2410003 | 6,110 | 240 | 0 | 1 | 0 ppb |
| Hilmar County Water District CA2410012 | 5,504 | 60 | 0 | 14 | 0 ppb |
| Planada CSD CA2410007 | 4,164 | 360 | 3 | 1 | 0 ppb |
| City of Merced CA2410009 | 93,692 | 1,260 | 4 | 0 | 0 ppb |
| City of Atwater CA2410001 | 29,479 | 480 | 10 | 0 | 0 ppb |
| Delhi Cwd CA2410006 | 7,784 | 240 | 2 | 0 | 0 ppb |
| Cal Am - Meadowbrook CA2410008 | 5,656 | 180 | 1 | 0 | 6 ppb |
| Le Grand Comm Services Dist CA2410011 | 1,739 | 0 | 0 | 8 | 0 ppb |
| Castle Airport CA2410700 | 1,650 | 0 | 0 | 1 | 6.9 ppb |
| San Luis Hills CA2400209 | 779 | 0 | 0 | 6 | 0 ppb |
| Volta Community Sd CA2400201 | 406 | 0 | 0 | 1 | 0 ppb |
| Black Rascal Water Company CA2400046 | 367 | 0 | 0 | 1 | 0 ppb |
| Ballico CSD CA2400167 | 238 | 0 | 0 | 1 | 7.4 ppb |
| Country Club County WD CA2400128 | 64 | 0 | 0 | 1 | 0 ppb |
| Vivos Xpoint SD4600414 | 40 | 0 | 0 | 1 | 1 ppb |
| Santa Nella County Water District CA2410018 | 2,211 | 0 | 0 | 0 | 0 ppb |
| John Latoracca Correctional Facility CA2400172 | 800 | 0 | 0 | 0 | 13.9 ppb |
| Aurora Acres RV Resort OR4193784 | 450 | 0 | 0 | 0 | 2.5 ppb |
| El Nido Mobile Home Park CA2400053 | 137 | 0 | 0 | 0 | 0 ppb |
| Evergreen Mobile Home Park CA2400084 | 36 | 0 | 0 | 0 | 0 ppb |
ZIP reports in Merced County
No ZIP report in this county is published yet.
These ZIP codes are covered by this overview because their utility has too little EPA data for a separate page: 95312, 95374.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.