S-G924-NRTFB-23 Coast of Georgia Georgia Coast NOAA NRT-Fernandina H13780 1 Savannah River and Delegal Creek Georgia United States 10000 2023 James Kirkpatrick Navigable Area 2023-02-27 2023-03-13 2023-03-16 Multibeam Echo Sounder Side Scan Sonar meters UTC Pacific Hydrographic Branch Any revisions to the Descriptive Report (DR) applied during office processing are shown in red italic text. The DR is maintained as a field unit product, therefore all information and recommendations within this report are considered preliminary unless otherwise noted. The final disposition of survey data is represented in the NOAA nautical chart products. All pertinent records for this survey are archived at the National Centers for Environmental Information (NCEI) and can be retrieved via https://www.ncei.noaa.gov/. Products created during office processing were generated in NAD83 UTM 17N, MLLW. All references to other horizontal or vertical datums in this report are applicable to the processed hydrographic data provided by the field unit. CC0-1.0 (NOAA Field Units) CC0-1.0 https://creativecommons.org/publicdomain/zero/1.0/ https://creativecommons.org/publicdomain/zero/1.0/legalcode These data were produced by NOAA and are in the public domain within the United States. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0). NOAA Survey H13780, located in the Savannah River and Delegal Creek, Georgia. 32.1352 81.14278900000001 31.863854 81.04807 Survey layout in Savannah River, plotted over ENC US5GA22M with multibeam coverage SupportFiles\Savannah_river_survey_area_coordinates.png Survey layout in Delegal Creek, plotted over ENC US5GA24M with multibeam coverage SupportFiles\Delegal_creek_survey_area_coordinates.png Survey areas of Delegal creek too shoal for surveying SupportFiles\Shoal_areas_delegal.png Investigation area in Savannah River unable to survey due to container ship docking SupportFiles\unable_to_survey_savannahriver.png Survey limits were acquired in accordance with the requirements in the Project Instructions and the HSSD. The Southeast Regional Navigation Manager has requested areas for new hydrographic surveys along the Georgia coast. The Pilots made a request to the Navigation Manager for investigation of three features in the Savannah River. First feature assigned for investigation is a pier in ruins at 32°08’01.73” – 081°08’32.19”. Second feature assigned for investigation is a 41 ft obstruction at 32°05’00.32” – 081°05’27.04”. The third feature assigned for investigation is a submerged wreck at 32°04’53.53” – 081°03’51.66”. The Navigation Manager has requested a hydrographic survey in Delegal Creek. Area is reported that the chart is not correctly charted and is in need of an update. 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 waters in survey area Object Detection Coverage (Refer to HSSD Section 5.2.2.2) Survey coverage was in accordance with the requirements listed above and in the HSSD. Survey coverage was in accordance with the requirements listed above and in the HSSD. H13780 MBES coverage Delegal Creek file:///M:/SG924NRTFB23/Surveys/H13780/01_HDR/Reports/Descriptive_Report/SupportFiles/MBES_coverage_Delegal.png H13780 SSS coverage Delegal Creek file:///M:/SG924NRTFB23/Surveys/H13780/01_HDR/Reports/Descriptive_Report/SupportFiles/SSS_delegal.png H13780 MBES coverage Savannah River file:///M:/SG924NRTFB23/Surveys/H13780/01_HDR/Reports/Descriptive_Report/SupportFiles/MBES_coverage_savannah_river.png H13780 SSS coverage Savannah River file:///M:/SG924NRTFB23/Surveys/H13780/01_HDR/Reports/Descriptive_Report/SupportFiles/SSS_savannah_river.png S3009 0.0 83.8 0.0 76.0 0.0 0.0 0.0 0.0 0.0 0.0 83.8 0.0 76.0 0.0 0.0 0.0 4.8 0.0 5.7 0 0 0 0 1.2 2023-03-13 2023-03-14 2023-03-15 2023-03-16 Acquisition spanned a total of 4 consecutive survey days. 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. S3009 10.5 1.2 S3009 file:///M:/SG924NRTFB23/Surveys/H13780/01_HDR/Reports/Descriptive_Report/SupportFiles/Boat.png All survey data for H13780 was collected by Navigation Response Team 2 and S3009. MBES Kongsberg Maritime EM 2040C SSS EdgeTech 4125 Positioning and Attitude System Applanix POS MV 320 v5 Sound Speed System AML Oceanographic MicroX SV Conductivity, Temperature, and Depth Sensor YSI CastAway-CTD Crosslines were collected in the Delegal Creek portion of the survey. They exceeded the required 4% coverage of mainscheme lines with a total of 5.7%. Crosslines were in good agreement with the mainscheme lines over the survey area with a mean difference of 0.0 m and a standard deviation of 0.1 m comparing 341,667 data points. Crossline statistics SupportFiles\crossline_difference.png ERS via VDATUM 0.0 15.5 ERS via VDATUM 0.0 12.5 S3009 2 N/A N/A .5 The vertical uncertainty of 15.5 cm refers to the Delegal Creek survey area while the 12.5 cm vertical uncertainty refers to the Savannah River survey area derived from project instructions. Sound speed uncertainty values derived from manufacturer specifications. No junction surveys assigned for H13780. Sonar system quality control checks were conducted as detailed in the quality control section of the DAPR. MBES data quality There were areas of very shallow water where the multibeam system experienced blowouts. This is typical of the system used in shallow water and data quality was improved as best as possible during data processing. There were also some holes in the multibeam surface in Savannah River due to a cable running along the edge of the survey area. Cable area is charted and is not shoaler than the charted least depth of 5.4 m so is not a hazard to navigation. Multibeam Blowout in Delegal Creek file:///M:/SG924NRTFB23/Surveys/H13780/01_HDR/Reports/Descriptive_Report/SupportFiles/MB_Blowouts.png Savannah River multibeam coverage over cable \SupportFiles\surface_savannah_river_cable.png Savannah River cable in Caris Subset Editor \SupportFiles\cable_savannah_river.png None Exist There were no other factors that affected corrections to soundings. As close to every 2 hours as possible. A total of 17 casts were taken during the 4 days of surveying. Real time sound speed was collected continuously at the multibeam transducer. 200% SSS with concurrent MBES was used on the Delegal Creek area and part of the Savannah River Area. In the westward deeper section of Savannah River, 100% MBES was achieved. All data reduction procedures conform to those detailed in the DAPR. All sounding systems were calibrated as detailed in the DAPR. A backscatter mosaic was created for this project. All equipment and survey methods were used as detailed in the DAPR. CARIS HIPS and SIPS 11.4.20 QPS FMGT 7.10.2 CARIS HIPS and SIPS 11.4.20 Caris_Support_Files_2022v2 H13780_MB_50cm_MLLW_Final CARIS Raster Surface (CUBE) 0.5 -1.4 18.4 NOAA_0.5m Object Detection H13780_SSSAB_1m_400kHz_1of2 SSS Mosaic 1 N/A 100% SSS H13780_SSSAB_1m_400kHz_2of2 SSS Mosaic 1 N/A 200% SSS H13780_SSSAB_1m_900kHz_1of2 SSS Mosaic 1 N/A 100% SSS H13780_SSSAB_1m_900kHz_2of2 SSS Mosaic 1 N/A 200% SSS H13780_MBAB_2m_S3009_300kHz_1of1 MB Backscatter Mosaic 2 N/A Object Detection The 900kHz SSS mosaics refer to the Delegal Creek area of the survey while the 400kHz SSS mosaics refer to the Savannah River portion. The frequencies were varied due to the differences in depth in the two areas. The multibeam surface was analyzed using the HydrOffice QC Tools Grid QA feature and the results are shown below. Density requirements for H13780 were achieved with at least 99% of surface nodes containing five or more soundings as required by HSSD Section 5.2.2.3. Pydro derived plot showing percent of nodes in compliance with HSSD density standards SupportFiles\H13780_MB_50cm_MLLW_Final.QAv6.density.png Pydro derived plot showing TVU compliance of H13780 multibeam surface SupportFiles\H13780_MB_50cm_MLLW_Final.QAv6.tvu_qc.png Two surfaces were created in review for submission to the NBS to differentiate the full bathy coverage on the northern area from the set line spacing full coverage in the southern area. These surfaces are named H13780_MB_50cm_MLLW_1of2 and H13780_MB_50cm_MLLW_2of2 Per FPM section 5.2.3.2.3 a HVCR report was not filed as horizontal and vertical control stations were not established by the field party for this survey. POSPAC data was logged to create a statistical best estimate of trajectory file (SBET) to help improve horizontal positioning. Vertical control was established with ERS via VDATUM. Mean Lower Low Water ERS via VDATUM S-G924_VDatum Limits_100m_NAD83-MLLW_geoid12b S-G924-NRB-23_Ossabaw_NAD83(2011)-MLLW Two separation models were used to cover the survey area. S-G924-NRB-23_Ossabaw_NAD83(2011)-MLLW was used for the Delegal Creek portion of the survey while S-G924_VDatum Limits_100m_NAD83-MLLW_geoid12b was used for the Savannah River section. North American Datum 1983 Projected UTM 17 RTX The Wide Area Augmentation System (WAAS) was used for real-time horizontal control during data acquisition. GPS Tide Dropout There was an issue discovered during data processing on one of the survey lines in Delegal Creek where the GPS tide dropped out for a short period of time resulting in unreliable multibeam soundings. The multibeam data where dropout occurred was rejected from the surface. GPS Tide Dropout SupportFiles\GPS_Tide_Dropout.PNG Multibeam soundings rejected from surface SupportFiles\GPS_tide_issue.png Many of the soundings taken in the Delegal Creek portion of the survey were not in agreement with the US5GA24M chart. Shoal areas are not charted correctly. The area has not been surveyed since 1934 and it is recommended to update the chart with the new soundings as quickly as possible. The soundings taken from the Savannah River portion of the survey are in agreement with the US5GA22M chart. Investigated features are included in the Final Feature File. Soundings comparison to ENC US5GA24M SupportFiles\sounding_chart_comparison.png Charted shoal area on ENC US5GA24M with deep soundings SupportFiles\charted_shoal_area_soundings.png US5GA22M 20000 58 2023-04-11 2023-04-11 US5GA24M 40000 31 2023-04-18 2023-04-18 Shoal areas in Delegal Creek are not charted correctly and need to be updated. Three DTONs were discovered and reported during data processing for this survey. Correspondence on DTONs can be found in Appendix II supplemental records. Features investigated can be found in the Final Feature File. Uncharted features are detailed in the Final Feature File. All channel depths in Savannah River are in agreement soundings on US5GA22. One DTON was reported near Hell's Gate Channel near Delegal Creek and can be found in the Final Feature File. Three ATONS in Delegal Creek were reported to the U.S. Coast Guard. Correspondence can be found in the Appendix II Supplemental Records. No Maritime Boundary Points were assigned for this survey. No bottom samples were required for this survey. No overhead features exist for this survey. Cables exist in the Savannah River area of survey. Cable areas are charted and soundings were deeper than charted least depths, no hazard to navigation exists. No platforms exist for this survey. There were ferrys operating from South Bank to North Bank in the Savannah River but no charted ferry routes on US5GA22M. No abnormal seafloor or environmental conditions exist for this survey. Present and/or planned construction or dredging exists within the survey limits, but was not investigated. The assigned area in the Savannah River that was unable to be surveyed due to port activity appeared to have active dredging operations nearby. No new surveys or further investigations are recommended for this area. No new ENC scales 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 Specifications and 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 Kirkpatrick Chief of Party 2023-05-11 Michael Coughlin Assistant Survey Technician 2023-05-11