FEMA's official flood map draws the 1%-annual-chance floodplain. FEMA's National Risk Index adds a comparative flood-risk rating for every census tract — a broader, neighborhood-scale measure. Here's how the tracts in and around San Jose rate, and how to check one address.
| Census tracts intersecting San Jose | 261 |
| … rated Relatively High or Very High for flood (riverine or coastal) | 167 |
That puts parts of the San Jose area among the higher-rated neighborhoods in FEMA's national flood-risk comparison. The National Risk Index rating is a comparative, composite measure (it reflects expected losses and community vulnerability, not just the mapped floodplain), so it complements the official FEMA flood map rather than contradicting it — check a specific address to see the map's call for one property. These are tract-level ratings (neighborhood scale), not parcel-precise and not a count of homes.
| Riverine flood — Very High | 56 |
| Riverine flood — Relatively High | 111 |
| Coastal flood — Very High | 3 |
| Coastal flood — Relatively High | 1 |
FEMA rates riverine and coastal flood separately, so one tract can appear in two rows — these rows can therefore add up to more than the 167 elevated tracts above (a tract is "elevated" if either rating is Relatively High or Very High). Categorical classes from FEMA's National Risk Index — never a proprietary score.
City figures are a starting point. To see what the official FEMA flood map will say for one property in San Jose — side by side with these cited federal & state sources — run the free per-address check:
Open the free Beyond-FEMA checker → · See all of Santa Clara County →
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