STOCKTON is served by 2 water providers on file with the EPA.
Data current as of July 2026
🔍Straight from EPA
🧪Real Lab Results
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Results for STOCKTON, CA
2 water providers on file serving this city.
Quick answer: STOCKTON's water has no violations on file and no single reading stands out against its peers (2 other providers in this area). It serves roughly 191,302 people, and the full breakdown below reflects everything EPA and California have on record for it.
Lead Summary
PFOS
Nitrate
Combined Uranium
Gross Alpha Particle Activity
Chromium, Hex
Totalhaloaceticacids (HAA5)
TTHM
Chloroform
Bromodichloromethane
Dichloroaceticacid
Trichloroaceticacid
Bromoform
Dibromochloromethane
Dibromoaceticacid
Copper, Free
Contaminants found
Metals
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0 mg/L (ppm)
Found at 2 providers
Combined Uranium
Detected: 6.4 PCI/L
9/24/2025
A naturally occurring radioactive metal. Long-term exposure above the legal limit is associated with kidney effects and increased cancer risk.
Chromium, Hex
Detected: 2.83 UG/L (ppb)
1/29/2025
Copper, Free
Detected: 29 UG/L (ppb)
9/11/2025
Disinfection Byproducts
Formed when chlorine used to disinfect water reacts with organic matter
Totalhaloaceticacids (HAA5)
Detected: 22 UG/L (ppb)
Found at 2 providers
TTHM
Detected: 66 UG/L (ppb)
Found at 2 providers
A group of disinfection byproducts formed when chlorine reacts with organic matter. Long-term exposure above the legal limit has been linked to increased cancer risk in some studies.
Chloroform
Detected: 60 UG/L (ppb)
Found at 2 providers
One of the individual trihalomethane disinfection byproducts, formed when chlorine reacts with organic matter.
Bromodichloromethane
Detected: 5.4 UG/L (ppb)
Found at 2 providers
Bromoform
Detected: 8.18 UG/L (ppb)
Found at 2 providers
Dibromochloromethane
Detected: 17.86 UG/L (ppb)
Found at 2 providers
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Nitrate
Detected: 4 MG/L (ppm)
8/12/2025
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
Properties
General water characteristics like pH, hardness, and cloudiness (turbidity)
Gross Alpha Particle Activity
Detected: 11.3 PCI/L
8/12/2025
PFAS & Emerging Contaminants
Human-made "forever chemicals" and other substances not yet fully regulated
PFOS
Detected: 0.0042 µg/L (ppb)
2/28/2023
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Other
Additional substances tested that don't fit neatly into the categories above
Dichloroaceticacid
Detected: 8.6 UG/L (ppb)
Found at 2 providers
Trichloroaceticacid
Detected: 11 UG/L (ppb)
Found at 2 providers
Dibromoaceticacid
Detected: 4.8 UG/L (ppb)
Found at 2 providers
Filtration considerations: General system types, not a specific product recommendation.