Walsh County, ND
drinking water quality
10,214 residents · 5 public water systems · 12 ZIP codes
EPA sampled 1 of 5 public water systems here, together serving about 4,284 people. EPA detected PFBA at 5.9 ng/L. EPA has not set a drinking water limit for PFBA, so there is no figure to compare it against. Last sampled 8/4/2025.
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 Walsh County
56744 · 58210 · 58227 · 58229 · 58231 · 58233 · 58237 · 58243 · 58250 · 58261 · 58270 · 58273
Readings are county-level, so every ZIP here shares the figure above. Search your ZIP on the map to see it in context.