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bowmanconsulting.com Research and Reconnaissance An online search of the FDEP web site (http://www.dep.state.fl.us/beaches/data/coastmon.htm) will be made for a current listing of the Range Monuments as defined in the latest addition of the RTBA listing. A records search for survey control will also be made for FDEP “A” monuments and/or National Geodetic Survey (NGS) 2nd order or higher marks. The values for this control can be found on the FDEP web site labins.org. Next, a site visit will be conducted and the range monuments and survey control will be searched for and located, the monument informa- tion reporting will commence. Any missing range monuments will be coordinated and accounted for. The azimuths for the profile lines will be computed, plotted on aerial imagery and loaded into the field data collection devices. Establish Control On-site control marks will be established from the found survey control. This on-site control controls the survey by occupying these marks with base station. The on-site marks will be included in the monument information report. The monuments will be constructed in a manner that keeps them safe from damage and can be relied upon throughout the life of the contract. All established control will exceed the Geospatial Positioning Accuracy Standards. Topographic Survey to be Completed by Bowman The survey will be completed by RTK GPS procedures. A base station will occupy a control mark that is within 1000’ of the profile line. Elevations and positions will be collected at 10’ to 20’ intervals, at all grade changes and topographic features (such as: vegetation lines, pavement, utility crossings etc.). Profile lines will be established at the range monuments on the published azimuths. The profiles will ex- tend seaward to a depth sufficient enough to have a 25’ overlap with the hydrographic survey data and landward to the Range monument or 150’ landward of the vegetation line which ever one is more landward. If there is an impassable obstruction the profile will terminate at that point and be noted accordingly. An independent check will be made on the survey control before and after each profile. Additional profile lines will l be established in the area of the Newport Pier to address those special concerns. All landward profiles will be completed during low tide to expose as much beach as possible and to ensure a sufficient overlap with the hydrographic portion of the survey. All the collected data will be stored in a data collector and documented in field books as outlined in the Standards. Additional Technologies to Consider • Bowman Consulting recommends performing a 3D laser scan of the beach area in the vicinity of the Newport Pier. This scan would produce a 3-dimensional point cloud and model that depicts the beach and the Newport Pier. Accurate measurements could then be made for comparisons between a series of scans completed over time. • Bowman recommends collecting additional data between the profiles. This task could be accomplished by mounting a GPS rover unit on to an ATV and set the unit to continually collect data. This task would identify areas of concern that may have been missed by the profiles. Once identified, additional profiles would be established. Also, a digital terrain model could be developed for the entire beach. • The entire beach area could be flown with Bowman’s survey and mapping grade fixed wing UAS. The UAS is not the typical drone; it is strictly a surveying and mapping tool that takes high resolution still imagery. The flight is preprogramed into a computer and the aircraft flies a specific mission and returns without an operator. Bowman has had excellent results utilizing this technology. The final product is a 3-dimensional point cloud that can be used for a digital terrain model or generating contours. Hydrographic Survey to be Completed by WSM Soundings will be collected using Odom CV-100 single or dual frequency fathometers interfaced to a DMS-10 Motion Sensor System. For horizontal vessel positioning, Trimble-based real-time Kinematic Global Positioning Systems (RTK) are utilized exclusively. For ves- sel navigation and data collection/storage, the Coastal Oceanographics “Hypack” system is used. This powerful computer based system effectively applies horizontal positioning to sounding data allowing real-time review of profile data in either plan view or cross section format. Profile surveys, encompassing automated hydrographic survey techniques will be conducted to meet or exceed the requirements outlined in the manuals published by the US Army Corps of Engineers, National Ocean Survey and the “Monitoring Standards for Beach Erosion Control” as published by the Florida Department of Environmental Protection, Bureau of Beach and Coastal Systems. Tab 3 Approach/Methodology Page 25