Water Quality: San Jose, CA

Indicates direct fecal contamination; associated with diarrhea, cramps, nausea, and potential severe illness.

Common source: Human and animal fecal waste

EPA limit: Zero tolerance (any positive triggers violations)

Alpha-emitting radioactive particles increase cancer risk, particularly from bone and other internal cancers.

Common source: Natural uranium and radium in geological formations

EPA limit: 15 pCi/L (excluding radon and uranium)

Causes neurological damage, developmental delays in children, and kidney damage in adults even at low exposure levels.

Common source: Old plumbing pipes, lead solder, brass fixtures

EPA limit: Action Level: 0.015 mg/L (15 ppb)

Trihalomethanes and haloacetic acids that increase cancer risk and may cause adverse reproductive outcomes.

Common source: Chlorine disinfection reacting with natural organic matter in source water

EPA limit: TTHM: 0.080 mg/L; HAA5: 0.060 mg/L

Total trihalomethanes are linked to increased risk of bladder cancer and adverse reproductive outcomes.

Common source: Reaction of chlorine disinfectants with naturally occurring organic matter in water

EPA limit: 0.080 mg/L (80 ppb)

Haloacetic acids are associated with increased cancer risk and potential reproductive and developmental effects.

Common source: Reaction of chlorine disinfectants with organic matter in treated water

EPA limit: 0.060 mg/L (60 ppb)

Not a direct health risk but reacts with disinfectants to form carcinogenic byproducts such as trihalomethanes.

Common source: Decaying plant material, algae, soil organic matter in source water

EPA limit: Treatment technique (must reduce TOC based on source water level)