How much flood risk does Allegan County actually carry?
Allegan County lands at the 79.4th percentile of FEMA's National Risk Index for flooding, "Relatively Moderate" territory — a middling flood hazard by national standards — 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 2 years. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Who actually carries the flood insurance FEMA requires
Allegan County 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 Allegan County, not just the ones FEMA mandates, 0.2% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
How Allegan County compares nationally
Allegan County sits at rank 678 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 527 of 3144 by population (1 is biggest). About 122,429 people live in Allegan County, Michigan, spread over 825.43 square miles.
What to do next if you own or are buying in Allegan County
Across all of Allegan County's 58,388 residential structures, 118 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 Allegan County's numbers. See the data quality guide for why Allegan County, like hundreds of other counties, doesn't get a clean compliance percentage.