County · California
Stanislaus County, California: drinking water records
This overview covers 25 ZIP codes and 70 community water systems in Stanislaus County. It also stands in for 0 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 |
|---|---|---|---|---|---|
| Turlock, City of CA5010019 | 72,682 | 300 | 0 | 1 | 0 ppb |
| Ceres, City of CA5010028 | 54,513 | 480 | 7 | 1 | 0 ppb |
| Riverbank, City of CA5010018 | 24,834 | 540 | 0 | 1 | 0 ppb |
| Oakdale, City of CA5010014 | 23,235 | 420 | 0 | 1 | 0 ppb |
| City of Newman-Water Department CA5010013 | 12,207 | 300 | 0 | 1 | 0 ppb |
| Hughson, City of CA5010008 | 7,481 | 180 | 0 | 36 | 0 ppb |
| Keyes Community Services Dist. CA5010009 | 5,672 | 60 | 0 | 14 | 0 ppb |
| Modesto, City of CA5010010 | 218,771 | 2,580 | 7 | 0 | 0 ppb |
| Patterson, City of CA5010017 | 24,977 | 360 | 0 | 0 | 0 ppb |
| City of Modesto - Salida CA5010005 | 14,537 | 120 | 0 | 0 | 0 ppb |
| City of Waterford CA5010006 | 8,788 | 240 | 0 | 0 | 0.6 ppb |
| Denair Community Services District CA5010021 | 5,090 | 240 | 0 | 0 | 0 ppb |
| King George Co. Courthouse VA6099050 | 3,985 | 180 | 0 | 0 | 0 ppb |
| Western Hills Water District/Diablo Gran CA5010039 | 2,000 | 0 | 0 | 2 | 0 ppb |
| Riverdale Park Tract CSD CA5000019 | 610 | 0 | 0 | 1 | 5 ppb |
| Cedar Grove Mobile Home Park TX0500043 | 595 | 0 | 0 | 3 | 0 ppb |
| Riverview Mobile Home Estates CA5000090 | 540 | 0 | 0 | 23 | 0 ppb |
| Crows Landing Comm Svc District CA5000005 | 500 | 0 | 0 | 1 | 0 ppb |
| Knights Ferry Comm. Svc. Dist. CA5000008 | 168 | 0 | 0 | 5 | 9.6 ppb |
| Lazy B Mobilehome Park CA5000048 | 125 | 0 | 0 | 2 | 0 ppb |
| Westley CSD CA5000408 | 70 | 0 | 0 | 1 | 0 ppb |
| Country Villa Apts CA5000218 | 60 | 0 | 0 | 37 | 0 ppb |
| Martin'S Mobile Home Court CA5000061 | 60 | 0 | 0 | 24 | 0 ppb |
| Cobles Corner CA5000033 | 50 | 0 | 0 | 33 | 0 ppb |
| Kgcsa-Dahlgren VA6099295 | 2,650 | 0 | 0 | 0 | 2.4 ppb |
ZIP reports in Stanislaus County
No ZIP report in this county is published yet.
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.