Texas Flood Screening Map
Check FEMA flood zones, FIRM panels, and map changes for any Texas address, coordinates, or site boundary.
Screening only — not a flood zone determination. Read the disclaimer.
Zipped shapefile (.shp, .shx, .dbf, and .prj), GeoJSON, or KML, up to 2,000 acres. Your file is read in your browser. Only the boundary outline is sent to the public map services that run the search; HERO E&C does not receive or store it.
Click the map to add corners. Click the first corner or press Finish boundary to close. Backspace removes the last corner; Esc cancels.
You can also click any point on the map.
Results
Search an address, enter coordinates, upload or draw a boundary, or click the map. Results appear here with their sources and dates.
How to read the results
- Flood zone and SFHA
- Zones beginning with A or V are in the Special Flood Hazard Area (SFHA), the area subject to the 1% annual chance flood (the base flood). Zone X (shaded) is the 0.2% annual chance flood hazard area; Zone X (unshaded) is an area of minimal flood hazard. Zone D is an area of possible but undetermined flood hazard.
- Floodway
- The channel and adjacent land that must be kept open to carry the base flood without raising flood levels more than a set amount. Development in the floodway is tightly restricted.
- Base flood elevation (BFE)
- The 1% annual chance water-surface elevation, usually in feet NAVD 88. Zone A has no BFE; Zone AO lists a flood depth instead.
- FIRM panel and effective date
- The Flood Insurance Rate Map panel that covers the site and the date it became effective. Use the panel number to make an official FIRMette at FEMA's Map Service Center.
- LOMR and LOMA
- Letters of Map Revision (LOMR) and Letters of Map Amendment (LOMA) change the effective FEMA map. A LOMR is already built into the flood zones shown here. A LOMA covers only the lot or building it names, so a LOMA near your site may not apply to it.
- Boundary results
- For an uploaded or drawn boundary, the tool reports the acres and percent of the site in each zone and how many building footprints touch the SFHA.
Data sources
| Layer | Source | Currency |
|---|---|---|
| Flood zones, BFEs, FIRM panels, LOMR/LOMA | FEMA National Flood Hazard Layer (public domain) | Queried live at the time shown in each result |
| Building footprints | FEMA USA Structures (ORNL / FEMA), via Esri Living Atlas, CC BY 4.0 | Texas data June 2025; buildings over 450 sq ft |
| Streams, water bodies, HUC-12 | USGS National Hydrography Dataset and Watershed Boundary Dataset (public domain) | As served by USGS |
| Edwards Aquifer zones | TCEQ (informational; not a survey) | As served by TCEQ |
| Basemaps | USGS The National Map (public domain) | As served by USGS |
| Address search | U.S. Census Bureau Geocoder | Current address ranges |
| Texas outline and county names | U.S. Census Bureau TIGERweb (public domain); outline simplified | Outline fetched Oct 2026; counties queried live |
Map software: ArcGIS Maps SDK for JavaScript. Powered by Esri.
Known gaps
- Preliminary and draft maps are not shown, including FEMA preliminary maps, SARA's Atlas 14 draft floodplains, and Harris County's MAAPnext drafts. Where they apply, the local notes in the results link to them.
- Local regulatory floodplains are not shown and can be wider than FEMA's, for example the City of Austin's fully developed floodplain and Williamson County's Atlas 14 floodplains (adopted March 2026).
- New LOMAs and LOMRs can take time to appear in FEMA's data, and Letters of Map Change issued before 1997 are not online.
- Address search can place a point on the wrong side of a street or at the wrong end of a block. Check the marker, and click the correct spot on the map if needed.
- FEMA draws flood zones only when the map is zoomed in (about 1:36,000 or closer). Results do not depend on the zoom level.
- Building footprints come from imagery of varying dates and exclude buildings under 450 sq ft.
- Ground elevations, rainfall depths, modeled flood depths, and current stream or weather conditions are not included.
- KMZ files are not supported yet; save the boundary as KML or GeoJSON.
Disclaimer
Informational screening only. This tool displays public data from the FEMA National Flood Hazard Layer (as served by FEMA at the time shown), FEMA USA Structures (via Esri Living Atlas), USGS, TCEQ, and the U.S. Census Bureau. Its results are not a flood zone determination, an Elevation Certificate, a Letter of Map Amendment or Revision, or a sealed engineering document, and they have not been reviewed by a licensed professional for your property. Do not use them for design, construction, bidding, or permitting.
Lenders make official flood zone determinations; building elevations are documented on an Elevation Certificate; only FEMA can change a flood zone. Results may not reflect preliminary or draft maps, local regulatory floodplains, or pending map changes, and an address search can place a site in the wrong location. Confirm with the official FIRM panel at FEMA's Map Service Center and your local floodplain administrator.
Using this tool does not create an engineer–client relationship. Files you upload are read in your browser; only the address you enter and the site location or boundary outline are sent to the public services listed above to run the search. HERO E&C does not receive or store your searches or files. HERO E&C · TBPELS Firm F-27793.
Need more than a screening?
HERO E&C prepares drainage and floodplain studies, HEC-HMS / HEC-RAS models, FEMA CLOMR/LOMR submittals, and development permit applications across Texas.