Turbidity in Drinking Water
EPA limits, health effects, and what to do if your water is affected.
🩨 Health Effects
High turbidity (cloudiness) can interfere with disinfection by allowing pathogens to hide behind particles. While not a direct health hazard, a turbidity violation indicates the filtration system may not be working properly, potentially allowing Giardia, Cryptosporidium, and viruses to pass through.
📍 Sources in Water
Caused by suspended particles including sediment, algae, and organic matter from natural erosion, stormwater runoff, or disturbance of sediment in distribution pipes. Surface water systems are especially susceptible after heavy rain.
✅ What To Do
Turbidity violations usually trigger a boil water advisory. Follow any advisory issued by your utility. To remove turbidity at home, use a sediment filter or reverse osmosis system. A 1 NTU limit applies generally; filtered systems must meet 0.3 NTU.
Check your tap water for Turbidity
Search your ZIP code to see if your water system has had Turbidity violations, plus lead testing results and an overall safety grade.
Search your ZIP code →Data from the EPA's Safe Drinking Water Information System (SDWIS). MCLs reflect minimum federal standards; some contaminants may pose health risks below these thresholds.