{ "currentVersion": 10.61, "id": 641, "name": "sfpcga_10b", "type": "Raster Layer", "description": "Digital flood-inundation maps for a 5.3-mile reach of South Fork Peachtree Creek from the Brockett Road bridge to the Willivee Driver bridge, DeKalb County, Georgia, were created by the USGS in cooperation with the cities of DeKalb County, Georiga. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage South Fork Peachtree at Casa Drive, near Clarkston, Georgia (02336152). Current conditions at the USGS streamgage may be obtained on the Internet. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the South Fork Peachtree at Casa Drive, near Clarkston (02336152) streamgage and documented high-water marks from recent floods. The hydraulic model was then used to determine 13 water-surface profiles for flood stages at 0.5-foot intervals referenced to the streamgage datum and ranging from bankfull (6.0 feet) to approximately 3.21 feet above the highest recorded water level at the streamgage. The flood-peak inundation area was modeled in a GIS by combining steady-state hydraulic modeling and available lidar digital elevation model (DEM) data. Information about the study, floods, and methods used can be found in the USGS Scientific Investigations Map 3347. http://dx.doi.org/10.3133/sim3347", "geometryType": null, "copyrightText": "", "parentLayer": null, "subLayers": [], "minScale": 0, "maxScale": 0, "defaultVisibility": false, "extent": { "xmin": -9384571.5712448, "ymin": 4002302.7215478057, "xmax": -9376589.649019705, "ymax": 4005394.3498364324, "spatialReference": { "wkid": 102100, "latestWkid": 3857 } }, "hasAttachments": false, "htmlPopupType": "esriServerHTMLPopupTypeNone", "displayField": "", "typeIdField": null, "subtypeFieldName": null, "subtypeField": null, "defaultSubtypeCode": null, "fields": null, "geometryField": {}, "indexes": [], "subtypes": [], "relationships": [], "canModifyLayer": false, "canScaleSymbols": false, "hasLabels": false, "capabilities": "Map,Query", "supportsStatistics": false, "supportsAdvancedQueries": false, "supportedQueryFormats": "JSON, AMF, geoJSON", "isDataVersioned": false, "ownershipBasedAccessControlForFeatures": {"allowOthersToQuery": true}, "useStandardizedQueries": true, "advancedQueryCapabilities": { "useStandardizedQueries": true, "supportsStatistics": false, "supportsHavingClause": false, "supportsCountDistinct": false, "supportsOrderBy": false, "supportsDistinct": false, "supportsPagination": false, "supportsTrueCurve": false, "supportsReturningQueryExtent": true, "supportsQueryWithDistance": true, "supportsSqlExpression": false }, "supportsCoordinatesQuantization": true }