{ "culture": "en-US", "name": "", "guid": "", "catalogPath": "", "snippet": "The inundation and overtopping layers and the associated analyses provide a regional-scale illustration of inundation and coastal flooding due to specific sea level rise and storm surge scenarios, and are intended to improve sea level rise awareness and preparedness.", "description": "

SLR Inundation Mapping<\/SPAN><\/P>

The topographic data used for this analysis were derived from topographic light detection and ranging (LiDAR) data from NOAA. The SLR inundation mapping was completed on a 1-meter (3.28-feet) digital elevation model (DEM) derived from the bare-earth LiDAR data. <\/SPAN><\/SPAN><\/P>

The inundation mapping effort leveraged existing and readily available model output from a large-scale MIKE21 San Francisco Bay hydrodynamic modeling effort completed as part of FEMA\u2019s San Francisco Bay Area Coastal Study (DHI 2013). The model takes into account water level variations associated with astronomical tides, storm surge, and El Nino effects. The FEMA model output was used to determine the daily and extreme tide levels throughout the study area for input to the SLR inundation mapping.<\/SPAN><\/SPAN><\/P>

The ten scenarios include 12, 24, 36, 48, 52, 66, 78, 84, 96, and 108 inches above current MHHW.<\/SPAN><\/SPAN><\/P>

Inundation maps were developed using the NOAA Coastal Services Center methods (Marcy et al. 2011). The initial step in creating the inundation maps was to create the inundated water surface DEM. Daily and extreme high tide elevations derived from the FEMA MIKE 21 model output points were used to define the water surface elevations for the existing and future conditions MHHW and 100-yr SWEL. The water surface elevations were then extended inland to project the water surface over the inundated topography. Depth of flooding raster files were created by subtracting the land-surface DEM from the water surface DEM. The resultant DEM provides both the inland extent and the depth of inundation in feet. The final step used in creating the depth and extent of flood maps relies on an assessment of hydraulic connectivity. The assessment of hydraulic connectivity removes areas from the inundation zone if they are protected by levees or other topographic features that are not overtopped.<\/SPAN><\/P><\/DIV><\/DIV><\/DIV>", "summary": "The inundation and overtopping layers and the associated analyses provide a regional-scale illustration of inundation and coastal flooding due to specific sea level rise and storm surge scenarios, and are intended to improve sea level rise awareness and preparedness.", "title": "Sea Level Rise: Overtopping and Inundation \u2013 City and County of San Francisco", "tags": [ "Sea Level Rise", "SLR Inundation", "Normalized Shoreline Elevation", "Overtopping Potential Depth", "Mean DEM elevation", "Mean MHHW elevation" ], "type": "", "typeKeywords": [], "thumbnail": "", "url": "", "minScale": 150000000, "maxScale": 5000, "spatialReference": "", "accessInformation": "AECOM 2017: (1) Justin Vandever (justin.vandever@aecom.com); (2) Mark Lightner (mark.lightner@aecom.com); (3) Mike Mak (michael.mak@aecom.com)\nAECOM 300 Lakeside Drive, Suite 400, Oakland, CA 94612", "licenseInfo": "

Disclaimer<\/SPAN><\/P>

The inundation maps and the associated analyses provide a regional-scale illustration of inundation and coastal flooding due to specific sea level rise and storm surge scenarios, and are intended to improve sea level rise awareness and preparedness. The maps are not detailed to the parcel-scale and should not be used for navigation, permitting, regulatory, or other legal uses. Flooding due to sea level rise and storm surges is possible in areas outside of those predicted in these maps, and the maps do not guarantee the safety of an individual or structure. Nor do the maps model flooding from other sources, such as riverine or surface water flooding from rainfall-runoff events. The contributors and sponsors of this product do not assume liability for any injury, death, property damage, or other effects of flooding. The maps relied on a 1-meter digital elevation model created from LiDAR data collected in 2010 and additional survey data (where available). Although care was taken to capture all relevant topographic features and coastal structures that may impact coastal inundation, it is possible that structures may not be fully represented, especially those that are narrower than the 1-meter horizontal map scale. The maps are based on model outputs and do not account for all of the complex and dynamic San Francisco Bay processes or future conditions such as erosion, subsidence, future construction or shoreline protection upgrades, or other changes to San Francisco Bay or the region that may occur in response to sea level rise.<\/SPAN><\/P><\/DIV><\/DIV><\/DIV>", "portalUrl": "" }