S-H929-NRT2-17Key West AnchoragesKey WestNRT2F007111Anchorages C,D,F and XFloridaUnited States50002017James KirkpatrickNavigable Area2017-11-072017-11-132017-11-18Multibeam Echo SounderSide Scan SonarMultibeam Echo Sounder BackscattermetersUniversal Transverse Mercator (UTM)UTCPacific Hydrographic BranchThe purpose of this survey is to provide contemporary surveys to update National Ocean Service (NOS) nautical charts. All separates are filed with the hydrographic data. Any revisions to the Descriptive Report (DR) generated during office processing are shown in bold red italic text. The processing branch maintains the DR as a field unit product, therefore, all information and recommendations within the body of the DR are considered preliminary unless otherwise noted. The final disposition of surveyed features is represented in the OCS nautical chart update products. All pertinent records for this survey, including the DR, are archived at the National Centers for Environmental Information (NCEI) and can be retrieved via http://www.ncei.noaa.gov/.NOAA24.545555555681.863736388924.505548055681.8174897222F00711 Survey Outline\SupportFiles\Survey Outline.PNGSurvey limits were acquired in accordance with the requirements in the Project Instructions and the HSSD.The Key West Pilots Association requested a hydrographic survey in Anchorages C, D, F and X, west of Main Channel Cut B. There is concern that there may be shoaling in the anchorages from the effects of Hurricane Irma. Survey data from this project is intended to supersede all prior survey data in the common area.The entire survey is adequate to supersede previous data.All Navigable watersObject Detection CoverageSurvey coverage was in accordance with the requirements listed above and in the HSSD.F00711 Survey Coverage\SupportFiles\Survey_Coverage.PNGS30090000069.587011.78100000069.587011.781016.9200003.372017-11-182017-11-172017-11-162017-11-152017-11-142017-11-13F00711 was completed in 6 survey days from 11/13/2017 - 11/18/2017.Refer to the Data Acquisition and Processing Report (DAPR) for a complete description of data acquisition and processing systems, survey vessels, quality control procedures and data processing methods. Additional information to supplement sounding and survey data, and any deviations from the DAPR are discussed in the following sections.S3009311.5Kongsberg MaritimeEM 2040CMBESEdgeTech4125SSSAML OceanographicMicroX SVSSound Speed SystemApplanixPOS MV 320 v5Positioning and Attitude SystemYSICastAway-CTDConductivity, Temperature, and Depth SensorAll major systems were utilized as described in the accompanying DAPR.Sounding data compares well between the crosslines and the mainscheme at intersecting areas. Higher standard deviations are attributed to areas of high slope. Crossline statistics were realized by creating a difference surface between the crosslines and mainscheme; then computing statistics.Crossline Statistics\SupportFiles\MBES Crossline Comparison Statistics.PNG00TCARIS300940.5Tide uncertainty is not applicable for this project. Tidal Constituent And Residual Interpolator (TCARI) automatically calculates the error associated with water level interpolation. This error is incorporated into the residual/harmonic solutions and included in the Total Propagated Error (TPE) for the survey.No junctioning surveys were provided for this project.Sonar system quality control checks were conducted as detailed in in the quality control section of the DAPR.None ExistThere were no conditions or deficiencies that affected equipment operational effectiveness.None ExistThere were no other factors that affected corrections to soundings.Office processing found a significant amount of "fliers" in the MBES data. These fliers appeared as noise in the MBES data which may have been the result of turbulent sea state / possibly highly aerated waters.Normally, a starting daily cast was taken at the beginning of work, and subsequent casts were taken during the survey day, when location, or variances of surface speed were observed to deviate greater than 2m/s, with a closing of day cast performed as well. No greater than 4 hours were allowed to elapse between casts.All equipment and survey methods were used as detailed in the DAPR.All data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Backscatter was not collected for this survey.Caris_Support_Files_5_6F00711_MB_50cm_MLLW_FinalCARIS Raster Surface (CUBE)0.53.214.7NOAA_0.5mMBES TracklineSBES Set Line SpacingF00711_SSS_1m_100SSS Mosaic1N/A100% SSSF00711_SSS_1m_200SSS Mosaic1N/A200% SSSF00711_MB_50cm_MLLWCARIS Raster Surface (CUBE)0.53.214.7NOAA_0.5mMBES TracklineSBES Set Line SpacingSurface Quality Control\SupportFiles\IHOness MBES Statistics.PNGF00711 QA Density\SupportFiles\F0071QAv5density.pngF00711 QA Depth\SupportFiles\F00711QAv5depth.pngF00711 QA Depth vs. Density\SupportFiles\F00711QAv5depth_vs_density.pngF00711 QA Depth vs. TVU\SupportFiles\F00711QAv5depth_vs_tvu_qcfull_range.pngF00711 QA TVU\SupportFiles\F00711QAv5tvu_qc.pngAdditional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterKey West, FL8724580TCARI8724580.tidFinal ApprovedH929NRT22017.tcFinal2018-01-252018-01-30North American Datum 1983Projected UTM 17Card Sound, FLCharts that overlap F00711 survey area include US5FL94M. A manual chart comparison was conducted by comparing soundings and features. Depths and features are in good agreement. USFL94M10000192017-11-072017-11-07falseSurvey data is in good agreement with ENC USFL94M. During office processing four new OBSTRN features were identified, added to the Final Feature File and recommended for addition to the chart.No Maritime Boundary Points were assigned for this survey. The wreck PA located at 24-31-13.279N // 081-49-50.809W was investigated and determined to exist approximately 20 meters to the west of the charted position.Wreck PASupportFiles\Wreck_PA.PNGThe field unit recommended "Retain" charted Wreck feature, remove PA and update position. Review did not concur with the field recommendation and recommended the Wreck PA feature as "Delete" and a "New" Wreck feature was added to the Final Feature File in the surveyed position and VALSOU attribute populated with the shoal depth.No uncharted features exist for this survey.During office processing four new OBSTRN features were identified, added to the Final Feature File and recommended for addition to the chart.No shoals or potentially hazardous features exist for this survey.Two (2) charted potentially hazardous WRECKS features exist for this survey. These were investigated by the field unit and included in the Final Feature File.No channels exist for this survey. There are no precautionary areas, safety fairways, traffic separation schemes, pilot boarding areas, or channel and range lines within the survey limits. The entire survey area is a designated anchorage.One MBES survey transect partially covered the maintained channel running north-south in the northeastern part of the survey area (Cut B Range). During office processing survey depths were compared to the channel controlling depth and survey depths were found to tend deeper (11.0 - 11.8 meters) than the channel controlling depth (10.8 meters).No bottom samples were required for this survey.All assigned shoreline features were investigated.No prior survey comparisons exist for this survey.ATON's in the survey area are properly charted and serve their intended purpose.No overhead features exist for this survey.No submarine features exist for this survey.No platforms exist for this survey.No ferry routes or terminals exist for this survey.No abnormal seafloor and/or environmental conditions exist for this survey.No present or planned construction or dredging exist within the survey limits.No new surveys or further investigations are recommended for this area.No new insets are recommended for this area.As Chief of Party, field operations for this hydrographic survey were conducted under my direct supervision, with frequent personal checks of progress and adequacy. I have reviewed the attached survey data and reports.All field sheets, this Descriptive Report, and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch.The survey data meets or exceeds requirements as set forth in the NOS Hydrographic Surveys and Specifications Deliverables, Field Procedures Manual, Letter Instructions, and all HSD Technical Directives. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required with the exception of deficiencies noted in the Descriptive Report.James KirkpatrickChief of Party2018-03-12