Water Quality: Olympia, WA

Can cause anemia in infants and young children; may cause nervous system effects at high levels.

Common source: Water treatment disinfectant used to control taste, odor, and microorganisms

EPA limit: 0.8 mg/L

Causes gastrointestinal illness; certain strains (e.g., O157:H7) can cause severe kidney failure and death.

Common source: Fecal contamination from humans or animals entering the water supply

EPA limit: Zero (no E. coli permitted in drinking water)

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)

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)