Reso 2008-1279 - Laserfiche WebLink

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270000-R Mr. A. John Szerlag June 4, 2008 Page 2 numerical wave modeling. Cross sections will be obtained at appropriate intervals to map the breakwaters and obtain a general representation of the project area. The survey data will be overlaid with applicable beach profile data obtained under Part 1 (a) service. The survey will be completed with a vessel-based automated hydrographic survey system consisting of a survey grade echo sounder to collect water depths and DGPS for horizontal positioning. Coastal Oceanographic HyPack software will be used to collect the survey data and for vessel navigation. An electronic tide gauge will be deployed and referenced to the vertical survey control for the breakwaters and beach profiles conducted by DERM. c. Base Map: Survey data collected in the field will be processed and reduced to the Florida State Plane coordinate system. Contours reflecting significant changes in the water depth within the hydrographic survey area will be established on the survey base map. In addition, available aerial photography will be incorporated into the map. d. Wave Modeling: Coastal Systems will utilize the state-of-the-art DHI MIKE21 Spectral Wave (SW) numerical wave model to conduct a wave propagation study to evaluate the effects of wave propagation from the offshore region to the nearshore region. The MlKE21 SW numerical wave model is a 3rd generation spectral wind-wave model that simulates the growth, decay, and transformation of wind-generated waves in offshore and coastal areas. The propagation of governing offshore wave events to the near-shore area will be simulated in order to evaluate the near-shore wave conditions, which are a principal mechanism in sediment transport. e. Sediment Transport Evaluation: Coastal Systems will evaluate the sediment transport characteristics in the project vicinity. Coastal Systems will combine the wave modeling results and the general sediment characteristics to assess the overall sediment movement. The assessment results will be utilized to understand the coastal processes at Sunny Isles Beach and to identify erosional hot spots for subsequent beach maintenance event and/or stabilization structure design. f. Evaluation of Critical Areas: Coastal Systems will evaluate and rank the individual areas experiencing erosion within the City of Sunny Isles Beach. The evaluation and ranking will be based on the coastal engineering analysis as well as site observations. For each area, the governing parameters relative to beach erosion will be identified and a recommended management action, as appropriate, to supplement existing federal and county beach management programs. The ranking will provide the necessary information for the City to prioritize the various beach management strategies that may be pursued. g. Initial Shoreline Stabilization Plan: Coastal Systems will prepare and present Phase 1 of the Sunny Isles Shoreline Stabilization study summarizing the results and findings of the engineering analyses. The report will summarize the numerical modeling results of the nearshore coastal processes that drive sediment transport and present the ranking of the critical beach erosion areas with supplemental management recommendations. The analysis Coastal, Environmental, Civil Engineering and Management