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vi. Model Results Reporting A modeling report will be prepared as an appendix to the BPP. The report will document the data collection, model setup, calibration, and specific results of the modeling effort. The information to be included will be as follows: • Model set-up and features. • Grid development and characteristics. A summary of the bathymetric and wave data used in the modeling and analysis. • An explanation of model calibration and application for the wave cases examined. • The parameters and processes utilized in the DeIft3D modeling package. The appendix will conform to FDEP's guidelines for DeIft3D modeling studies. Task 6: Coastal Modeling -Vulnerability Analysis CPE will perform a storm damage vulnerability analysis for Indian River County. The analysis will utilize the Storm Induced Beach Change Model, SBEACH, developed by Larson and Kraus (Larson and Kraus, 1989) for the US Army Corps of Engineers (USACE). SBEACH 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. 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. The current assessment is that the available data should be sufficient. CPE will develop a suite of storms for 4 different return intervals (5-years, 10-years, 20-years, and 30- years). Each return interval will have 6 distinct storms. Each of the storms will have one characteristic (wave height, peak wave period, or storm stage) that matches the value of the return interval for that characteristic. The other characteristics will be scaled in relation to the scaling of the characteristic intended to match the return interval. For example, if the maximum offshore wave height for a 5-year storm event is 20 feet, then we would take an actual storm event that had a maximum wave height of 16 feet and increase all the storm characteristics by 25%. The model will be run for all 119 profile lines within the County. With 24 storm events per profile, a total of 2,856 model runs will be performed. The pre and post-storm profiles will be compared for each storm event and the most landward reduction in profile height by 0.5 feet and 1.0 feet identified. This will be translated to a plan view location within a GIS map. Thus an area of expected "land loss" and expected damage can be estimated for each return interval. CPE will calculate the expected land loss and the associated land value along the length of the County. CPE will include the expected damage costs on a structure by structure basis if the County can provide, in GIS format, structure values and locations. It is beyond the scope of this work to digitize the outline of each structure and match its value from County Property records. This additional effort would provide a more accurate assessment of projected damage but is 35