Alternative Text Description for DFIRM 100 Year Floodplain

TABLE OF CONTENTS

MAP OVERVIEW

This map displays the 100-year floodplain areas across the state of Florida. The map shows areas that have a 1% annual chance of flooding, representing locations at significant flood risk. This is a raster dataset that delineates which portions of Florida fall within or outside the 100-year floodplain designation based on Digital Flood Insurance Rate Map (DFIRM) data.

GEOGRAPHIC CONTEXT

The map covers the entire state of Florida, from the Georgia and Alabama borders in the north to the Florida Keys in the south. Major cities labeled on the map include Jacksonville on the northeast coast, Orlando in the central region, Tampa on the west coast, Palm Bay on the east coast, and Palm Coast northeast of Orlando. The map extends slightly into southern Georgia and Alabama, showing portions of the Coastal Plain region including cities like Dothan and Albany. The map is bounded by the Atlantic Ocean to the east and the Gulf of America to the west and south. Notable landmarks visible include Dry Tortugas National Park and Great White Heron National Wildlife Refuge in the southernmost Keys, and Everglades National Park in southern Florida.

KEY INSIGHTS

The 100-year floodplain coverage is extensive throughout Florida, reflecting the state's low-lying topography and vulnerability to flooding. The most significant pattern is the widespread distribution of floodplain areas along both coastlines, with particularly dense coverage in southern Florida including the Everglades region. The interior portions of central Florida show less floodplain coverage, appearing as lighter areas on the map, while coastal regions and areas along major waterways show heavy floodplain designation. Northern Florida shows moderate floodplain coverage with a dendritic pattern that follows river systems and tributaries. The extensive floodplain areas in southwest Florida and throughout the peninsula's southern tip indicate substantial flood risk in these low-elevation regions.

VISUAL ELEMENTS

DFIRM 100 Year Floodplain

This layer represents areas within the 100-year floodplain designation based on Digital Flood Insurance Rate Map data.

100 Year Floodplain Areas (bright blue)

Appearance:

Areas designated as 100-year floodplain are displayed in bright blue, creating a dense network across much of Florida's landscape.

Distribution:

Floodplain areas are distributed throughout Florida with the heaviest concentration in coastal zones, southern Florida, and along river corridors. Coverage extends inland following drainage patterns and low-lying areas.

Notable locations:

Extensive floodplain coverage appears in the Everglades region of southern Florida, along both the Atlantic and Gulf of America coastlines, throughout the Florida Keys, around Tampa Bay, and along major river systems in northern Florida. The panhandle region shows moderate coverage with patterns following coastal areas and river valleys.

Spatial patterns:

The floodplain areas form dendritic branching patterns in northern and central Florida that correspond to river systems and their tributaries. Coastal areas show broad swaths of floodplain designation extending inland. Southern Florida displays nearly continuous floodplain coverage reflecting the low elevation and wetland character of the region. Central Florida's interior shows breaks in coverage where higher elevation areas exist.

Non-Floodplain Areas (tan/beige)

Appearance:

Areas outside the 100-year floodplain are shown in tan or beige color, appearing as negative space between the blue floodplain areas.

Distribution:

Non-floodplain areas are concentrated in the interior portions of central Florida, in the central ridge area, and in scattered higher-elevation locations throughout the state.

Notable locations:

The largest continuous non-floodplain areas appear in central Florida between Orlando and Lakeland, in portions of the northern interior, and in some upland areas of the panhandle.

Spatial patterns:

Non-floodplain areas form irregular patches that represent higher ground, becoming smaller and more fragmented toward coastal regions and southern Florida.

SYMBOL GUIDE

ADDITIONAL INFORMATION

This map represents flood hazard areas based on DFIRM (Digital Flood Insurance Rate Map) data, which is used for flood insurance rate determination and floodplain management. The 100-year floodplain, also known as the Special Flood Hazard Area, has a 1% chance of being equaled or exceeded in any given year. This raster dataset was derived from the DFIRM_FLDHAZ vector layer and provides a simplified view of floodplain boundaries across Florida. The map is designed to help identify areas at risk of flooding for planning, insurance, and emergency management purposes.

DATA CONTEXT

Data Source:

This data is derived from Digital Flood Insurance Rate Maps (DFIRM), which are created through hydrologic and hydraulic analyses conducted by the Federal Emergency Management Agency (FEMA) and its partners. The raster dataset is based on the DFIRM_FLDHAZ vector layer and has been processed into a 10-meter cell size format. Source layer: DFIRM_100_DEC24

Definition Query:

No definition query or data filter was applied. The map displays the complete dataset showing all areas classified as within or outside the 100-year floodplain.

Scale Information:

The map displays statewide coverage at a scale appropriate for viewing the entire state of Florida. The 10-meter cell size raster resolution is suitable for regional and statewide visualization. For site-specific floodplain determinations, users should consult detailed DFIRM products at larger scales.

Coordinate System:

NAD_1983_HARN_Florida_GDL_Albers (WKID 3087)

Time Period of Content:

The dataset designation indicates December 2024 (DEC24), representing the most current DFIRM data available as of that date.

Limitations:

This is a raster representation with 10-meter cells, which provides a generalized view compared to the source vector data. DFIRM data is updated periodically, and floodplain boundaries may change based on new studies, development, or environmental changes. This map should not be used as the sole source for flood insurance or regulatory determinations. Users should consult official FEMA Flood Insurance Rate Maps and local floodplain administrators for site-specific flood zone determinations.

Map Coverage:

The map covers the entire state of Florida and portions of southern Georgia and Alabama for geographic context. Coverage extends from approximately the Georgia-Alabama border in the north to the Dry Tortugas in the south, and from the Gulf of America coast in the west to the Atlantic Ocean in the east, including all Florida Keys.

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