Knott County, KY
drinking water quality
13,438 residents · 4 public water systems · 21 ZIP codes
EPA sampled 1 of 4 public water systems here, together serving about 7,056 people. Last sampled 9/10/2025.
What this means
PFAS are industrial chemicals that EPA describes as breaking down only very slowly in the environment. In April 2024 EPA set the first enforceable national limits: 4 ng/L for PFOA and PFOS, 10 ng/L for PFHxS, PFNA and GenX.
These figures are county-level and come from EPA’s sampling of public water systems. They describe the worst result found in the county, not what comes out of any particular tap — that depends on which system serves the address, and on the plumbing in the building. A private well is not covered by this programme at all.
ZIP codes in Knott County
41640 · 41643 · 41722 · 41725 · 41740 · 41759 · 41772 · 41773 · 41817 · 41822 · 41828 · 41831 · 41834 · 41836 · 41839 · 41843 · 41844 · 41847 · 41859 · 41861 · 41862
Readings are county-level, so every ZIP here shares the figure above. Search your ZIP on the map to see it in context.