How much flood risk does Sweet Grass County actually carry?
Sweet Grass County lands at the 19.7th percentile of FEMA's National Risk Index for flooding, "Very Low" territory — among the lowest flood hazard in the country — with the hazard driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 3 years. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Sweet Grass County's flood-insurance compliance gap
Homes with a federally backed mortgage inside Sweet Grass County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 3.8% of them do — 6 active policies against 157 structures FEMA counts in that zone, leaving a real compliance gap. Across all residential structures in Sweet Grass County, not just the ones FEMA mandates, 0.5% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Sweet Grass County ranks
Sweet Grass County sits at rank 2568 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2901 of 3144 by population (1 is biggest). About 3,757 people live in Sweet Grass County, Montana, spread over 1,855.536 square miles.
Your street may differ from Sweet Grass County's average
Across all of Sweet Grass County's 3,093 residential structures, 14 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Sweet Grass County's numbers. The guide to what the Special Flood Hazard Area actually means explains why the mandatory-insurance rule exists and who it applies to.