Data Sources
HazardProfile uses free, publicly available data from US federal agencies. Here's where each data type comes from.
FEMA NFIP — Flood Zone Data
Source: Federal Emergency Management Agency — National Flood Insurance Program
Flood zone designations are based on FEMA Flood Insurance Rate Maps (FIRMs). These maps are produced through detailed hydrological modeling and field surveys. Each designation (AE, X, VE, etc.) indicates the estimated annual probability and type of flooding for an area.
Coverage: All 50 states + territories · Updated: Periodically by FEMA; community-level updates vary · Authority: Official FEMA regulatory maps
FEMA Flood Map Service Center →USGS Earthquake Hazards Program
Source: US Geological Survey — Earthquake Hazards Program
Earthquake history data is sourced from the USGS FDSN Event API, which provides access to the USGS earthquake catalog. This includes magnitude, depth, location, and date for all recorded earthquakes going back decades. HazardProfile loads M4.0+ earthquakes for the contiguous US over the past 5 years; the national overview page highlights the most recent M4.5+ events, while city profile pages show all M4.0+ within 50 miles.
Coverage: Nationwide, M4.0+ · Updated: Real-time (loaded periodically to database) · API: earthquake.usgs.gov/fdsnws/event/1/query
USGS Earthquake API →USFS Wildfire Hazard Potential (WHP)
Source: US Forest Service — Rocky Mountain Research Station
Wildfire risk scores are based on the USFS Wildfire Hazard Potential (WHP) dataset, a national raster index measuring the relative potential for wildfire that would be difficult to control. WHP integrates fuel conditions (vegetation type, moisture, and loading), topography, and historical fire weather data into a continuous 30-meter resolution raster.
Coverage: Contiguous US · Updated: Annually (latest dataset) · Resolution: 30-meter raster, summarized to city/county level
USFS WHP Dataset →US Census Bureau — Geocoding & Geographies
Source: US Census Bureau — Geocoder API + Population Estimates + Gazetteer
Address lookups are geocoded (converted to latitude/longitude) using the free US Census Bureau Geocoder API. The site's city anchor pages are seeded from the Census Population Estimates Program (PEP) sub-est2023 file joined to the 2023 Census Gazetteer Places file — the top 1,000 incorporated places by 2023 population estimate. ZIP code anchor pages are seeded from the 2023 ZCTA Gazetteer (centroids).
Coverage: All US addresses · Auth: Free, no key required · API: geocoding.geo.census.gov/geocoder
IRS Statistics of Income — ZIP-Level Returns
Source: Internal Revenue Service — Statistics of Income (SOI) ZIP Code Data
ZIP code pages are ranked by the IRS SOI ZIP-level tax return data, specifically the count of total exemptions (N2) per ZIP — a strong proxy for population that's freely available with no API key. HazardProfile uses this to select the top ~5,000 most-populated ZIPs nationwide for pre-rendered profiles.
Coverage: All US ZIPs with IRS filings · Updated: Annually (~1 year lag) · File: 22zpallnoagi.csv
IRS SOI ZIP Code Data →Data Accuracy Disclaimer
HazardProfile aggregates publicly available federal data for informational purposes. Flood zone designations may not reflect the most recent FEMA map amendments (LOMAs). Earthquake data is historical and does not predict future events. Wildfire risk scores represent long-term potential, not real-time conditions. For official flood determinations required for mortgage or insurance purposes, consult the FEMA Flood Map Service Center directly.