2023-05-23 07:23:40.74 2023-06-06 11:37:24.25 editor:esri.dijit.metadata.editor 1.0 FGDC CSDGM Metadata FGDC false 377b6152a9e44aeaa0b4463ab2b76a5a Rachael Hartofelis Metropolitan Transportation Commission rhartofelis@bayareametro.gov USGS Coastal Storm Modeling System United States Geological Survey Data and Visualation Metropolitan Transportation Commission dataviz@bayareametro.gov 2023-05-23 07:23:40.74 Framework Shoreline Inventory: 4.9 ft TWL 2023-01-01 2023-05-01 <div><b>Dataset Background: the Sea Level Rise Adaptation Funding and Investment Framework</b></div><div><b><br /></b></div><div>The Framework assumed a threshold adaptation height to determine the scope of the analysis. The assumption focused on near-term inundation to align with other planning efforts. As such, the Framework relied on 2050 projections for permanent inundation by the <a href='https://www.opc.ca.gov/webmaster/ftp/pdf/agenda_items/20180314/Item3_Exhibit-A_OPC_SLR_Guidance-rd3.pdf' target='_blank' rel='nofollow ugc noopener noreferrer'>California Ocean Protection Council published in 2018</a>, plus an extreme storm surge scenario to meet state guidance recommendations to “<a href='https://www.opc.ca.gov/webmaster/ftp/pdf/agenda_items/20200226/OPC-2020-2025-Strategic-Plan-FINAL-20200228.pdf' target='_blank' rel='nofollow ugc noopener noreferrer'>Ensure California’s coast is resilient to at least 3.5 feet of sea level rise by 2050</a>” and to coincide with many local planning efforts. The Framework uses 4.9 feet of Total Water Level (TWL) to identify adaptation vulnerability and protection.</div><div><br /></div><div>The planning year and height assumptions were also based on the 2018 State of California Sea-Level Rise Guidance prepared by the Ocean Protection Council, which is widely used throughout the state for planning and permitting purposes. BCDC formally adopted the Guidance in 2018 and it is currently considered “best available science” for regional sea level rise scenarios. The Ocean Protection Council recommended projections for 2050 range from 1.1-2.7 feet. Staff also used regional precedents to support the inundation assumption. In Plan Bay Area 2050, one, two, and three feet of inundation were studied before a final two foot assumption for permanent inundation was used for the final plan. However, the state released updated guidance to plan for a minimum of 3.5 feet of sea level rise after initial Plan assumptions were set. </div><div><b><br /></b></div><div>The project team determined an approach to sum two values: a sea level rise projection height for the 2050 horizon year and additional height to account for temporary flooding risk from storms. The Framework used the 2018 Ocean Protection Council’s 5% probability for 2050, which projects 1.4 feet of permanent inundation from sea level rise, combined with a 100 year storm, which is estimated to add 3.5 feet above MHW. The combined projected permanent inundation plus a 100 year storm is 4.9 feet TWL.</div><div><b><br /></b></div><div>The 4.9 foot assumption also allowed staff to align with currently available flood data layers. The 150 cm (or 4.9 foot) layer in United States Geological Survey Coastal Storm Modeling System mapping data was selected as the best available layer to study vulnerability in the Bay and Outer Coast. The dataset was selected based on how widely it was used in the industry, analytical ease, extensive availability of inundation heights, data resolution, and geographic coverage across the Bay and Outer Coast.</div><div><b><br /></b></div><div><b>Dataset Source: Our Coast, Our Future</b></div><div>Additional flood heights are available from Our Coast, Our Future. Our Coast, Our Future is a partnership between Point Blue Conservation Science and the USGS Pacific Coastal and Marine Science Center, and continues to be collaboratively developed with many local, state, and federal partners as it expands its geography. It will eventually provide sea level rise and storm scenarios for the entire coast of California.</div><div><b><br /></b></div><div>It was originally launched in 2011 and focused on the San Francisco Bay and outer coast area (Half Moon Bay to Bodega Head). The USGS led the modeling, Point Blue Conservation Science developed the online platform and supported end-user engagement, and staff from the Greater Farallones National Marine Sanctuary, Corovai, the San Francisco Bay National Estuarine Research Reserve, and NOAA’s Office for Coastal Management led a technical assistance and outreach effort to co-develop the tool with end-users.</div><div><b><br /></b></div><div>Projected flood exposure data are from the USGS Coastal Storm Modeling System (CoSMoS v2.x; Barnard et al. 2019), accessed via the Our Coast Our Future web platform (Point Blue Conservation Science and USGS 2023).</div><div><b><br /></b></div><div><b><i>For additional information on how the data was developed, please see:</i></b></div><div><i>Barnard, P.L., Erikson, L.H., Foxgrover, A.C., Finzi Hart, J.A., Limber, P., O’Neill, A.C., van Ormondt, M., Vitousek, S., Wood, N., Hayden, M.K., and Jones, J.M., 2019. Dynamic flood modeling essential to assess the coastal impacts of climate change. Scientific Reports, Volume 9, Article #4309, 13 pp., https://dx.doi.org/10.1038/s41598-019-40742-z</i></div><div><br /></div> The dataset represents 4.9 feet of inundation, including projected sea level rise inundation through 2050 and an extreme storm for the Bay Area. Layer created in support of the Sea Level Rise Adaptation Funding and Investment Framework. USGS Coastal Storm Modeling System (CoSMoS v2.x; Barnard et al. 2019), accessed via the Our Coast Our Future web platform (Point Blue Conservation Science and USGS 2023). resiliencesea level risenatural hazardfloodingflood risk Rachael Hartofelis Metropolitan Transportation Commission rhartofelis@bayareametro.gov USGS Coastal Flood Modeling System United States Geological Survey Data and Visualization Metropolitan Transportation Commission dataviz@bayareametro.gov The OCOF platform was developed in collaboration with the decision-making audience that it was intended to support, including land use planners, coastal resource managers, restoration managers, hazard mitigation planners, floodplain managers, emergency services managers, stormwater managers, municipal engineers, municipal leaders, zoning and permitting officials, public works officials, and conservation organizations. Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints Other Constraints https://services3.arcgis.com/i2dkYWmb4wHvYPda/arcgis/rest/services/USGS_flooding/FeatureServer USGS Coastal Storm Modeling System, 4.9 feet TWL Layer showing 4.9 feet TWL of shoreline inundation. USGS CoSMoS OBJECTID Value created by ArcGIS to organize the data. ArcGIS ObjectID 1 GRIDCODE Default value assigned by USGS CoSMoS - value is 1. USGS CoSMoS Integer 1 Collection Created by ArcGIS; no set value. ArcGIS String 1 GEOID Unique identifier created by ArcGIS. ArcGIS Integer 1 Shape_Length Value assigned to establish geometry in ArcGIS. ArcGIS Single 1 Shape_Area Value assigned to establish geometry in ArcGIS. ArcGIS Single 1