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November 15, 2018 Page 3 of 7 information can be used for planning of future renourishment and maintenance events. Information used for the task will be based solely on data collected and analyzed by others such as the current data being collected in the southern borrow area with vibracores and the investigation into the feasibility of upland sand sources in the area. Task 5: Storm Vulnerability Stantec will provide a vulnerability assessment that will include performing a storm damage vulnerability analysis by utilizing the Storm Induced Beach Change Model (SBEACH) which simulates changes in the beach profile that could result from coastal storms of varying intensity in terms of storm tide levels, wave heights. wave periods, and storm duration. This assessment will follow a similar approach, to those used in previous BPP updates. Information required as input to run the SBEACH model includes the beach cross-section, the median sediment grain size, and the time histories of the wave height, wave period, and water elevation. This information will be gathered from existing data sources. No new collection of data is proposed. If it is determined that the available data is insufficient to develop an accurate model, then collection of additional data will be discussed with the County. Sea level rise will be discussed as it relates to the management strategies and how the County can include sea level rise in their planning efforts. This discussion will be restricted to the impacts of sea level rise on the proposed beach management strategies but will also include a narrative on the Florida Statute requirements for local governments to prepare comprehensive plans to include sea level rise considerations in their future planning documents. Impacts of sea level rise to infrastructure close to the beach will not be included. Task 6: Storm Damage Reduction Analysis The analysis of potential storm damages will be followed by an evaluation of the size of a beach fill that would be required to eliminate the potential damage identified with a particular storm return interval. SBEACH will be re -run to determine the size of a beach fill that would be needed to eliminate that potential threat. This process will be repeated for each storm and each reach for which potential damages are indicated. The outcome of this analysis will be a list of beach fill dimensions needed in each reach to eliminate storm damage threats to structures for storm return interval deemed to pose a potential threat. It is anticipated that no more than three storm intervals will be used for this analysis. The results of this analysis can be used to formulate a beach nourishment strategy that would seek to equalize the magnitude of the storm damage risk for the entire County or at least reduce the risk to an acceptable level. The determination of what constitutes an acceptable level of risk depends on priorities established by the County. Stantec will work with the County to identify and confirm these priorities.