How much flood risk does St. Charles Parish actually carry?
St. Charles Parish lands at the 95.4th percentile of FEMA's National Risk Index for flooding, "Very High" territory — among the highest flood hazard in the country — with the hazard driven by coastal storm surge rather than inland rivers — FEMA's model puts a surge event here at about 3.8 times a year. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Mandatory flood insurance compliance in St. Charles Parish
St. Charles Parish is one of the counties where FEMA's own denominator for mandated flood-zone structures is missing, so no compliance rate is shown rather than a guessed one — the data quality guide covers how common this is. Across all residential structures in St. Charles Parish, not just the ones FEMA mandates, 55.7% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
St. Charles Parish against the rest of the country
St. Charles Parish sits at rank 159 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 1003 of 3144 by population (1 is biggest). St. Charles Parish, Louisiana covers 277.742 square miles and counts roughly 50,400 residents.
What to do next if you own or are buying in St. Charles Parish
Across all of St. Charles Parish's 17,783 residential structures, 9,907 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 St. Charles Parish's numbers. See the data quality guide for why St. Charles Parish, like hundreds of other counties, doesn't get a clean compliance percentage.