The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). In addition to the preceding, required text, the Abstract should also describe the projection and coordinate system as well as a general statement about horizontal accuracy.

The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The Floodplain Mapping/Redelineation flood risk boundaries are derived from the engineering information Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA).

Flood Zones map of the City of Mobile. (effective June 5, 2020) Size 36x48 / Format PDF. Updated as needed.Descripton of Flood Zone Data:The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.

description: The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the Alabama West (FIPS 2703) State Plane projection and coordiante system The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.; abstract: The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the Alabama West (FIPS 2703) State Plane projection and coordiante system The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.

Key features include:

Search by address or parcel to quickly locate flood zone status.

Map visualization of FEMA-designated flood zones including high-risk and moderate-to-low risk areas.

Overlay options for city limits, parcels, and other relevant geographic data.

Useful for property development, insurance purposes, emergency planning, and risk assessmen

The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.

This map shows the base flood elevations for the 1% annual chance flood in the United States.The National Flood Hazard Layer (NFHL) is a compilation of GIS data that comprises a nationwide digital Flood Insurance Rate Map. The GIS data and services are designed to provide the user with the ability to determine the flood zone, base flood elevation, and floodway status for a particular location. It also has information about the NFIP communities, map panels, cross sections, hydraulic structures, Coastal Barrier Resource System, and base maps such as road, stream, and public land survey data. Through flood studies, FEMA produces Flood Insurance Study Reports, FIRM Panels, and FIRM Databases. FIRM Databases that become effective are incorporated into the NFHL. Updates to the NFHL are issued through Letters of Map Revision (LOMRs) and Letters of Map Amendment (LOMAs). Continuously updated, the NFHL serves as a Digital Flood Insurance Rate Map representing the current effective flood data for those communities where maps have been digitized. NFHL data can be viewed with widely available GIS software, including freely available programs that work with GIS shapefiles. For more information on the NFHL, see the online resources referenced herein. Using base maps: The minimum horizontal positional accuracy for base map hydrographic and transportation features used with the NFHL is the NSSDA radial accuracy of 38 feet. Letter of Map Amendment (LOMA) point locations are approximate. The location of the LOMA is referenced in the legal description of the letter itself. LOMA points can be viewed in the NFHL Interactive Map on the FEMA GeoPlatform on the HIFLD Open Data Portal.Sourced from the HIFLD Open Data Portal for FEMA National Flood Hazard Layers.

Quick Start This is a collection of flood datasets to support hydrologic research for Hurricane Irma in Florida-Georgia, August-September 2017. The best way to start exploring this collection is by opening the Hurricane Irma 2017 Story Map [http://arcg.is/PSOKH]. It has separate tabs for the different content categories, and links to the relevant HydroShare resources within this collection. For more information on this hurricane archive project, as well as links to Hurricanes Harvey and Maria data archives, see the CUAHSI public page on the Hurricane 2017 Archives. [1]

More Details This is the root collection resource for management of hydrologic and related data collected during Hurricane Irma, primarily in Florida, Georgia, and neighboring states within the storm's wind swath. This collection holds numerous composite resources comprising streamflow forecasts, inundation polygons and depth grids, flooding impacts, elevation grids, high water marks, and numerous other related information sources. Building outlines (polygons) for the affected states are also provided, to help understand storm impacts.

The data providers for this collection are the NOAA National Weather Service, NOAA National Hurricane Center, NOAA National Water Center, FEMA, 9-1-1 emergency communications agencies, and many others.

User-contributed resources from 2017 US Hurricanes may also be shared with The CUAHSI 2017 Hurricane Data Community group [2] to make them accessible to interested researchers, Anyone may join this group.

This collection has been produced by work on a US National Science Foundation RAPID Award "Archiving and Enabling Community Access to Data from Recent US Hurricanes" [4].

References [1] CUAHSI Projects > Hurricane 2017 Archives [https://www.cuahsi.org/projects/hurricanes-2017-data-archive ] [2] CUAHSI 2017 Hurricane Data Community group [https://www.hydroshare.org/group/41] [3] Hurricane Irma 2017 Archive Story Map [http://arcg.is/PSOKH] [4] NSF RAPID Grant [https://nsf.gov/awardsearch/showAward?AWD_ID=1761673]

This layer depicts flood plains (zones A & B) and FIRMs in and around the City of Auburn as delineated by FEMA.

Remotely sensed imagery is increasingly used by emergency managers to monitor and map the impact of flood events to support preparedness, response, and critical decision making throughout the flood event lifecycle. To reduce latency in delivery of imagery-derived information, ensure consistent and reliably derived map products, and facilitate processing of an increasing volume of remote sensing data-streams, automated flood mapping workflows are needed. The U.S. Geological Survey is facilitating the development and integration of machine-learning algorithms in collaboration with NASA, National Geospatial Intelligence Agency (NGA), University of Alabama, and University of Illinois to create a workflow for rapidly generating improved flood-map products. A major bottleneck to the training of robust, generalizable machine learning algorithms for pattern recognition is a lack of training data that is representative across the landscape. To overcome this limitation for the training of a ...

This resource links to the Hurricane Irma 2017 Story Map (Esri ArcGIS Online web app) [1] that provides a graphical overview and set of interactive maps to download flood depth grids, flood extent polygons, high water marks, stream gage observations, National Water Model streamflow forecasts, and several other datasets compiled before, during and after Hurricane Irma.

References [1] Hurricane Irma Story Map [https://arcg.is/19z9jL]

Referenced external maps Irma crowdsource photos story map (NAPSG) [https://arcg.is/1WOr4b]

This digital elevation model (DEM) is a part of a series of DEMs produced for the National Oceanic and Atmospheric Administration Coastal Services Center's Sea Level Rise and Coastal Flooding Impacts Viewer (www.csc.noaa.gov/slr/viewer). This metadata record describes the DEM for Mobile County in Alabama and Escambia, Santa Rosa, and Okaloosa (southern coastal portion only) Counties in Florida. The DEM includes the best available lidar data known to exist at the time of DEM creation for the coastal areas of Mobile County in Alabama and Escambia, Santa Rosa, and Okaloosa (portion) counties in Florida, that met project specification.This DEM is derived from the USGS National Elevation Dataset (NED), US Army Corps of Engineers (USACE) LiDAR data, as well as LiDAR collected for the Northwest Florida Water Management District (NWFWMD) and the Florida Department of Emergency Management (FDEM). NED and USACE data were used only in Mobile County, AL. NWFWMD or FDEM data were used in all other areas. Hydrographic breaklines used in the creation of the DEM were obtained from FDEM and Southwest Florida Water Management District (SWFWMD). This DEM is hydro flattened such that water elevations are less than or equal to 0 meters.This DEM is referenced vertically to the North American Vertical Datum of 1988 (NAVD88) with vertical units of meters and horizontally to the North American Datum of 1983 (NAD83). The resolution of the DEM is approximately 5 meters. This DEM does not include licensed data (Baldwin County, Alabama) that is unavailable for distribution to the general public. As such, the extent of this DEM is different than that of the DEM used by the NOAA Coastal Services Center in creating the inundation data seen in the Sea Level Rise and Coastal Impacts Viewer (www.csc.noaa.gov/slr/viewer).The NOAA Coastal Services Center has developed high-resolution digital elevation models (DEMs) for use in the Center's Sea Level Rise And Coastal Flooding Impacts internet mapping application. These DEMs serve as source datasets used to derive data to visualize the impacts of inundation resulting from sea level rise along the coastal United States and its territories.The dataset is provided "as is," without warranty to its performance, merchantable state, or fitness for any particular purpose. The entire risk associated with the results and performance of this dataset is assumed by the user. This dataset should be used strictly as a planning reference and not for navigation, permitting, or other legal purposes.

Presentation given at TopoBathy Workshop Sept 17-18, 2019, Tuscaloosa, Alabama.

Flood inundation is difficult to map, model, and forecast because of the data needed and the computational demand. Recently an approach based on the relative elevation, or Height Above Nearest Drainage (HAND), which is derived from a digital elevation model (DEM), has been suggested for both flood mapping and obtaining reach hydraulic properties and synthetic rating curves. These products are only as good as the underlying DEM from which they are derived and thus better inland bathymetry offers the potential for incorporating bathymetry into national scale models to improve flood inundation modeling and mapping. This presentation will review the approach for using relative elevation in flood modeling, describing how HAND is calculated, how it is used to map flood inundation for stream reach catchments and how it is used to determine stream reach properties, identifying shortcomings and giving ideas for improvements. As we obtain more detailed information on bathymetry, topography and hydrography it is important to establish a consistent data model for the river bed that is used in HAND related work that aligns and reconciles elevation and hydrography. This presentation will discuss approaches for using hydrography to remove DEM obstacles, the segmentation of streams used in deriving HAND reach average hydraulic properties and ideas for quantifying reach average roughness based on HAND and flood inundation mapped from remote sensing of previous floods with measured discharges.

A Google Earth Engine implementation of the Floodwater Depth Estimation Tool (FwDET) This is a Google Earth Engine implementation of the Floodwater Depth Estimation Tool (FwDET) developed by the Surface Dynamics and Modeling Lab at the University of Alabama that calculates flood depth using a flood extent layer and a digital elevation model. This research is made possible by the CyberSeed Program at the University of Alabama. Project name: WaterServ: A Cyberinfrastructure for Analysis, Visualization and Sharing of Hydrological Data. GitHub Repository (ArcMap and QGIS implementations): https://github.com/csdms-contrib/fwdet Cohen, S., A. Raney, D. Munasinghe, J.D. Loftis J, A. Molthan, J. Bell, L. Rogers, J. Galantowicz, G.R. Brakenridge7, A.J. Kettner, Y. Huang, Y. Tsang, (2019). The Floodwater Depth Estimation Tool (FwDET v2.0) for Improved Remote Sensing Analysis of Coastal Flooding. Natural Hazards and Earth System Sciences, 19, 2053–2065. https://doi.org/10.5194/nhess-19-2053-2019 Cohen, S., G. R. Brakenridge, A. Kettner, B. Bates, J. Nelson, R. McDonald, Y. Huang, D. Munasinghe, and J. Zhang (2018), Estimating Floodwater Depths from Flood Inundation Maps and Topography, Journal of the American Water Resources Association, 54 (4), 847–858. https://doi.org/10.1111/1752-1688.12609 Sample products and data availability: https://sdml.ua.edu/models/fwdet/ https://sdml.ua.edu/michigan-flood-may-2020/ https://cartoscience.users.earthengine.app/view/fwdet-gee-mi https://alabama.app.box.com/s/31p8pdh6ngwqnbcgzlhyk2gkbsd2elq0 GEE implementation output: fwdet_gee_brazos.tif ArcMap implementation output (see Cohen et al. 2019): fwdet_v2_brazos.tif iRIC validation layer (see Nelson et al. 2010): iric_brazos_hydraulic_model_validation.tif Brazos River inundation polygon access in GEE: var brazos = ee.FeatureCollection('users/cartoscience/FwDET-GEE-Public/Brazos_River_Inundation_2016') Nelson, J.M., Shimizu, Y., Takebayashi, H. and McDonald, R.R., 2010. The international river interface cooperative: public domain software for river modeling. In 2nd Joint Federal Interagency Conference, Las Vegas, June (Vol. 27). Google Earth Engine Code /* ---------------------------------------------------------------------------------------------------------------------- # FwDET-GEE calculates floodwater depth from a floodwater extent layer and a DEM Authors: Brad G. Peter, Sagy Cohen, Ronan Lucey, Dinuke Munasinghe, Austin Raney Emails: bpeter@ua.edu, sagy.cohen@ua.edu, ronan.m.lucey@nasa.gov, dsmunasinghe@crimson.ua.edu, aaraney@crimson.ua.edu Organizations: BP, SC, DM, AR - University of Alabama; RL - University of Alabama in Huntsville Last Modified: 10/08/2020 To cite this code use: Peter, Brad; Cohen, Sagy; Lucey, Ronan; Munasinghe, Dinuke; Raney, Austin, 2020, "A Google Earth Engine implementation of the Floodwater Depth Estimation Tool (FwDET-GEE)", https://doi.org/10.7910/DVN/JQ4BCN, Harvard Dataverse, V2 ------------------------------------------------------------------------------------------------------------------------- This is a Google Earth Engine implementation of the Floodwater Depth Estimation Tool (FwDETv2.0) [1] developed by the Surface Dynamics and Modeling Lab at the University of Alabama that calculates flood depth using a flood extent layer and a digital elevation model. This research is made possible by the CyberSeed Program at the University of Alabama. Project name: WaterServ: A Cyberinfrastructure for Analysis, Visualization and Sharing of Hydrological Data. GitHub Repository (ArcMap and QGIS implementations): https://github.com/csdms-contrib/fwdet ------------------------------------------------------------------------------------------------------------------------- How to run this code with your flood extent GEE asset: User of this script will need to update path to flood extent (line 32 or 33) and select from the processing options. Available DEM options (1) are USGS/NED (U.S.) and USGS/SRTMGL1_003 (global). Other options include (2) running the elevation outlier filtering algorithm, (3) adding water body data to the inundation extent, (4) add a water body data layer uploaded by the user rather than using the JRC global surface water data, (5) masking out regular water body data, (6) masking out 0 m depths, (7) choosing whether or not to export, (8) exporting additional data layers, and (9) setting an export file name. The simpleVis option (10) bypasses the time consuming processes and is meant for visualization only; set this option to false to complete the entire process and enable exporting. ------------------------------------------------------------------------------------------------------------------------- ••••••••••••••••••••••••••••••••••••••••••• USER OPTIONS •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Load flood extent layer | Flood extent layer must be uploaded to GEE first as an asset. If the flood extent is a shapefile, upload as a FeatureCollection; otherwise, if the flood extent layer is a raster, upload it as an image. A raster layer may be required if the flood extent is a highly complex geometry -------------------------------------- */ var flood = ee.FeatureCollection('users/username/folder/flood_extent') // comment out this line if using an Image // var flood = ee.Image('users/username/folder/flood_extent') // comment out this line if using a FeatureCollection var waterExtent = ee.FeatureCollection('users/username/folder/water_extent') // OPTIONAL comment out this line if using an Image // var waterExtent = ee.Image('users/username/folder/water_extent') // OPTIONAL comment out this line if using a FeatureCollection // Processing options - refer to the directions above /*1*/ var demSource = 'USGS/NED' // 'USGS/NED' or 'USGS/SRTMGL1_003' /*2*/ var outlierTest = 'TRUE' // 'TRUE' (default) or 'FALSE' /*3*/ var addWater = 'TRUE' // 'TRUE' (default) or 'FALSE' /*4*/ var userWater = 'FALSE' // 'TRUE' or 'FALSE' (default) /*5*/ var maskWater = 'FALSE' // 'TRUE' or 'FALSE' (default) /*6*/ var maskZero = 'FALSE' // 'TRUE' or 'FALSE' (default) /*7*/ var exportLayer = 'TRUE' // 'TRUE' (default) or 'FALSE' /*8*/ var exportAll = 'FALSE' // 'TRUE' or 'FALSE' (default) /*9*/ var outputName = 'FwDET_GEE' // text string for naming export file /*10*/ var simpleVis = 'FALSE' // 'TRUE' or 'FALSE' (default) // ••••••••••••••••••••••••••••••••• NO USER INPUT BEYOND THIS POINT •••••••••••••••••••••••••••••••••••••••••••••••••••• // Create buffer around flood area to use for clipping other layers var area = flood.geometry().bounds().buffer(1000).bounds() // Load DEM and grab projection info var dem = ee.Image(demSource).select('elevation').clip(area) // [2,3] var projection = dem.projection() var resolution = projection.nominalScale().getInfo() // Load global surface water layer var jrc = ee.Image('JRC/GSW1_1/GlobalSurfaceWater').select('occurrence').clip(area) // [4] var water_image = jrc // User uploaded flood extent layer // Identify if a raster or vector layer is being used and proceed with appropriate process if ( flood.name() == 'FeatureCollection' ) { var addProperty = function(feature) { return feature.set('val',0); }; var flood_image = flood.map(addProperty).reduceToImage(['val'],ee.Reducer.first()) .rename('flood') } else { var flood_image = flood.multiply(0) } // Optional user uploaded water extent layer if ( userWater == 'TRUE' ) { // Identify if a raster or vector layer is being used and proceed with appropriate process if ( waterExtent.name() == 'FeatureCollection' ) { var addProperty = function(feature) { return feature.set('val',0); }; var water_image = waterExtent.map(addProperty).reduceToImage(['val'],ee.Reducer.first()) .rename('flood') } else { var water_image = waterExtent.multiply(0) } } // Add water bodies to flood extent if 'TRUE' is selected if ( addWater == 'TRUE' ) { var w = water_image.reproject(projection) var waterFill = flood_image.mask().where(w.gt(0),1) flood_image = waterFill.updateMask(waterFill.eq(1)).multiply(0) } // Change processing options if 'TRUE' is selected if ( simpleVis == 'FALSE' ) { flood_image = flood_image.reproject(projection) } else { outlierTest = 'FALSE' exportLayer = 'FALSE' } // Run the outlier filtering process if 'TRUE' is selected if ( outlierTest == 'TRUE' ) { // Outlier detection and filling on complete DEM using the modified z-score and a median filter [5] var kernel = ee.Kernel.fixed(3,3,[[1,1,1],[1,1,1],[1,1,1]]) var kernel_weighted = ee.Kernel.fixed(3,3,[[1,1,1],[1,0,1],[1,1,1]]) var median = dem.focal_median({kernel:kernel}).reproject(projection) var median_weighted = dem.focal_median({kernel:kernel_weighted}).reproject(projection) var diff = dem.subtract(median) var mzscore = diff.multiply(0.6745).divide(diff.abs().focal_median({kernel:kernel}).reproject(projection)) var fillDEM = dem.where(mzscore.gt(3.5),median_weighted) // Outlier detection and filling on the flood extent border pixels var expand = flood_image.focal_max({kernel: ee.Kernel.square({ radius: projection.nominalScale(), units: 'meters' })}).reproject(projection) var demMask = fillDEM.updateMask(flood_image.mask().eq(0)) var boundary = demMask.add(expand) var medianBoundary = boundary.focal_median({kernel:kernel}).reproject(projection) var medianWeightedBoundary = boundary.focal_median({kernel:kernel_weighted}).reproject(projection) var diffBoundary = boundary.subtract(medianBoundary) var mzscoreBoundary = diffBoundary.multiply(0.6745).divide(diffBoundary.abs().focal_median({kernel:kernel}).reproject(projection)) var fill =

This map was created to help assess impacts on nonindigenous aquatic species distributions due to flooding associated with Hurricane Nate. Storm surge and flood events can assist expansion and distribution of nonindigenous aquatic species through the connection of adjacent watersheds, backflow of water upstream of impoundments, increased downstream flow, and creation of freshwater bridges along coastal regions. This map will help natural resource managers determine potential new locations for individual species, or to develop a watch list of potential new species within a watershed. These data include a subset of data from the Nonindigenous Aquatic Species Database, that fall within the general area of the 2017 Hurricane Nate flooding.

Tropical Storm Cindy caused significant impacts across Central Alabama, including heavy rainfall, localized flooding, and spawned two tornadoes including the Fairfield EF-1 Tornado in Jefferson County and Anita EF-0 Tornado in Shelby County. Local Storm Reports, Storm-Based Warning polygons, and official storm survey information is included within the map. For more information about this event, visit https://www.weather.gov/event_cindy2017