Portsmouth city, VA: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Portsmouth city scores at the 64.2th percentile for flood hazard, rated "Relatively Moderate" — a middling flood hazard by national standards. The hazard here is driven by coastal storm surge rather than inland rivers — FEMA's model puts a surge event here at about 3.6 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Who actually carries the flood insurance FEMA requires
FEMA hasn't published a residential structure count for Portsmouth city'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, 9.6% of all residential structures in Portsmouth city carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
How Portsmouth city compares nationally
Among the 3144 US counties FEMA scores for flood hazard, Portsmouth city ranks 1175 — 1 being the highest hazard nationally — and 644 by population among all 3144 counties covered here, where 1 is the largest. About 96,482 people live in Portsmouth city, Virginia, spread over 33.301 square miles.
Your street may differ from Portsmouth city's average
3,057 of Portsmouth city's 31,904 residential structures carry flood coverage of some kind, per FEMA's latest count — useful context, not a substitute for checking one parcel.
Where Portsmouth city's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. Portsmouth city'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.