Alternative Text Description for DFIRM 500 Year Floodplain

TABLE OF CONTENTS

MAP OVERVIEW

This map displays the 500-year floodplain areas across the state of Florida. The map shows areas that have a 0.2% annual chance of flooding, representing zones at moderate to low risk of flooding based on Digital Flood Insurance Rate Map (DFIRM) data. The floodplain areas are shown in turquoise against a gray background representing areas outside the 500-year floodplain.

GEOGRAPHIC CONTEXT

The map covers the entire state of Florida, extending from the panhandle region in the northwest to the Florida Keys in the south. Major cities labeled on the map include Jacksonville on the northeast coast, Orlando in central Florida, Tampa and St. Petersburg on the west coast, and Miami in the southeast. The map also shows portions of neighboring states including Georgia to the north (with cities like Savannah, Albany, and Valdosta labeled) and Alabama to the northwest (with Dothan labeled). The map displays both of Florida's extensive coastlines: the Atlantic Ocean to the east and the Gulf of America to the west. The Florida Keys archipelago is visible extending southwest from the southern tip of the peninsula.

KEY INSIGHTS

The 500-year floodplain areas show extensive coverage throughout Florida, with particularly notable concentrations in several distinct patterns. Coastal areas along both the Atlantic and Gulf of America shorelines show significant floodplain coverage, especially in southern Florida from Cape Coral through the Everglades region to Miami. The northern panhandle region displays dense floodplain coverage, particularly in low-lying coastal and river valley areas. Central Florida shows a more scattered distribution with floodplain areas concentrated along major river corridors and lake systems. The extensive floodplain coverage in southern Florida reflects the region's low elevation and complex wetland systems, while interior portions of the peninsula show areas of higher ground interspersed with floodplain zones following drainage patterns.

VISUAL ELEMENTS

DFIRM 500 Year Floodplain Layer

This layer represents areas within the 500-year floodplain based on Digital Flood Insurance Rate Map raster data with 10-meter cell resolution.

500 Year Floodplain Areas (turquoise solid fill)

Appearance:

Solid turquoise or cyan colored areas covering portions of the state.

Distribution:

Floodplain areas appear throughout Florida with varying density. The most extensive continuous coverage occurs in southern Florida, the panhandle coastal zone, and along major river systems. The eastern and western coastal margins show substantial floodplain coverage, while interior highlands show less coverage.

Notable locations:

Spatial patterns:

Floodplain areas follow clear geographic patterns related to topography, hydrology, and coastal proximity. Linear patterns along river corridors extend inland from both coasts. Coastal floodplain zones vary in width, with broader zones in areas of gentler topography and narrower zones where higher ground approaches the coast. Interior floodplain areas form branching patterns following drainage networks and natural low-lying terrain.

Non-Floodplain Areas (gray background)

Appearance:

Light gray areas representing land outside the 500-year floodplain designation.

Distribution:

Non-floodplain areas appear throughout the state, most prominently in the central ridge region of the peninsula, portions of northern Florida, and scattered higher elevation areas.

Notable locations:

Spatial patterns:

Non-floodplain areas appear as gray zones interspersed among the turquoise floodplain coverage, creating a mosaic pattern that reflects Florida's subtle but significant topographic variation.

SYMBOL GUIDE

ADDITIONAL INFORMATION

The 500-year floodplain represents areas with a 0.2% probability of flooding in any given year, or a moderate to low flood risk over time. This designation is used for flood insurance purposes and land use planning. Properties within the 500-year floodplain face lower flood risk than those in the 100-year floodplain but still have measurable flood exposure. This map is derived from official DFIRM (Digital Flood Insurance Rate Map) data and represents regulatory flood zones. The extensive floodplain coverage visible in Florida reflects the state's generally low elevation, extensive coastline, numerous rivers and wetlands, and vulnerability to storm surge from hurricanes. The map displays data at a resolution appropriate for regional planning and general awareness; property-specific flood determinations require consultation of detailed FIRM panels.

DATA CONTEXT

Data Source:

This data is derived from Digital Flood Insurance Rate Maps (DFIRM) produced by the Federal Emergency Management Agency (FEMA). The raster dataset was created from the DFIRM_FLDHAZ vector layer and represents flood hazard zones at 10-meter cell resolution. Source layer: DFIRM_500_DEC24

Definition Query:

Information not available.

Scale Information:

The map shows the entire state of Florida at a regional scale suitable for understanding statewide floodplain patterns. The 10-meter cell size of the underlying raster data provides moderate resolution appropriate for regional to local-scale analysis.

Coordinate System:

NAD_1983_HARN_Florida_GDL_Albers (WKID 3087)

Time Period of Content:

Data current as of December 2024.

Limitations:

This map represents the 500-year floodplain based on available data and modeling as of the publication date. Flood risk assessments are subject to change based on new studies, changed conditions, or improved mapping techniques. The 10-meter raster resolution may not capture all local variations in flood risk. Users requiring property-specific flood determinations should consult official FIRM panels and contact local floodplain administrators. Climate change, development, and changes to natural systems may affect actual flood risk over time.

Map Coverage:

The map covers the entire state of Florida from the panhandle to the Keys, with portions of southern Georgia and southeastern Alabama visible for geographic context. The mapped extent includes all of Florida's mainland and coastal islands, providing complete coverage of the state's flood hazard zones.

The alternative text description of this map was AI-generated and may contain inaccuracies.