Massac County, IL: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Massac County scores at the 43th percentile for flood hazard, rated "Relatively Low" — below the national norm for flood hazard. The hazard here is driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 4.2 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Mandatory flood insurance compliance in Massac County
FEMA hasn't published a residential structure count for Massac County's mapped flood zone, so a reliable mandatory-compliance percentage can't be computed here — see the data quality guide for why this gap exists for roughly a quarter of US counties. Looking beyond the mandated zone, 2.1% of all residential structures in Massac County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Massac County against the rest of the country
Among the 3144 US counties FEMA scores for flood hazard, Massac County ranks 1855 — 1 being the highest hazard nationally — and 2180 by population among all 3144 counties covered here, where 1 is the largest. Massac County, Illinois covers 237.152 square miles and counts roughly 13,627 residents.
What to do next if you own or are buying in Massac County
FEMA counts 6,254 residential structures in Massac County overall, 134 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
Where Massac County's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. Massac County's compliance figure is one of the ones affected by FEMA's incomplete denominator data — the data quality guide explains what that means and how many counties it touches.