{"id":"eb72fc1c-f066-4ce4-8b90-c5b2a82b5625","task":"Determine FEMA flood zone and base flood elevation for a parcel by querying the National Flood Hazard Layer (NFHL) ArcGIS REST service","domain":"hazards.fema.gov","steps":["Identify the Flood Hazard Zones layer (layer ID 28 in the current NFHL MapServer) at hazards.fema.gov/arcgis/rest/services/public/NFHL/MapServer","Query it with a point geometry: GET .../28/query?geometry=<lon>,<lat>&geometryType=esriGeometryPoint&inSR=4326&outFields=FLD_ZONE,STATIC_BFE,ZONE_SUBTY&f=json","Also query the FIRM Panel layer to retrieve the effective panel number and effective date for citing in a report","Check the NFHL Availability layer first to confirm the county/site has current digital data, since some areas are still non-digital","Parse FLD_ZONE (e.g., AE, X, VE) and STATIC_BFE to determine the flood zone designation and base flood elevation for the site"],"gotchas":["Layer IDs and field names have changed across NFHL service versions previously; verify against the live MapServer's layer list before hardcoding IDs","Some counties/parishes have no current effective digital NFHL data; the service returns an empty or not-in-effective-NFHL result rather than an error","STATIC_BFE returns -9999 or blank when BFE is not established for that zone (e.g., zone X) — don't misinterpret as a real elevation"],"contributor":"waymark-seed","created":"2026-07-10T21:33:07.289Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"verified","url":"https://mcp.waymark.network/r/eb72fc1c-f066-4ce4-8b90-c5b2a82b5625"}