OPR-R390-KR-23 Approaches to Nome, AK Norton Sound, AK eTrac H13694 2 300m Set Line Spacing MBES 8 NM West of Dall Point Alaska United States 40000 2023 David Neff, C.H. Basic Hydrographic Survey 2023-03-01 2023-08-09 2023-08-10 Multibeam Echo Sounder Multibeam Echo Sounder Backscatter meters UTC Pacific Hydrographic Branch All times are UTC. The purpose of this survey is to update existing NOS nautical charts. H13694 covers approximately 34 square nautical miles in the Bering Sea, Alaska. 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 3N, 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 Contractors) CC0-1.0 https://creativecommons.org/publicdomain/zero/1.0/ https://creativecommons.org/publicdomain/zero/1.0/legalcode These data were produced under contract with NOAA and any potential copyright was assigned to NOAA. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0). Contractor eTrac conducted hydrographic survey operations in the Bering Sea, Alaska. H13694 covers approximately 34 square nautical miles of survey area. 235.39 linear nautical miles were acquired during the survey. Survey was conducted within these limits between August 9, 2023 (DN221) and August 10, 2023 (DN222). 61.67519722222222 166.64968055555553 61.47954166666667 166.4901111111111 Survey Limits Overview (light blue area) file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_SurveyLimits_Overview.png Survey Limits (black line) file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_SurveyLimits.png All data were acquired in accordance with the requirements in the project instructions and specifications set forth in the Hydrographic Survey Specifications and Deliverables 2022 Edition (HSSD 2022). The purpose of this survey is to update existing National Ocean Service (NOS) nautical charts. The entire survey is adequate to supersede previous data. Survey H13694 is accurate to International Hydrographic Organization (IHO) Order 1a as required per the HSSD 2022. All waters in sheet 2 300m Set Line Spacing MBES in accordance with the requirements listed below and HSSD 2022. All waters in survey area Collect a minimum of 13,210 LNMs. All significant shoals or features found in waters less than 20m deep shall be developed to complete coverage standards, or a set line spacing density suitable to delineate the 5m depth contour as determined in consultation with the COR. If navigationally significant differences exist between charted and surveyed depths, contact the COR and summarize the findings. Denser set line spacing may be required following consultation with the COR. Survey coverage was in accordance with the requirements listed above and in the HSSD. Survey Coverage file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_SurveyCoverage.png R/V Norseman II 0.0 149.6 0.0 0.0 0.0 0.0 0.0 20.2 0.0 ASV Inez 0.0 65.59 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 215.18 0.0 0.0 0.0 0.0 0.0 20.2 0.0 9.39 3 0 0 0 34.0 2023-08-09 2023-08-10 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. R/V Norseman II 35.0 4.0 ASV Inez 7.0 0.56 The R/V Norseman II is a 35 meter steel research vessel that originally served as a Bering Sea commercial fishing vessel. It is equipped with a custom over-the-side pole mount with secondary tie point. ASV Inez is a 7 meter Wave Adaptive Modular Vessel (WAM-V) which is an innovative class of watercraft using unique suspension technology to radically improve seagoing capabilities. ASV Inez is equipped with a custom sonar mount. MBES R2Sonic 2022 MBES R2Sonic 2024 Sound Speed System AML Oceanographic MicroX SV Sound Speed System AML Oceanographic BaseX2 Sound Speed System AML Oceanographic MVP-X Positioning and Attitude System R2Sonic I2NS Positioning and Attitude System Applanix POS MV WaveMaster Note: R/V Norseman II utilized a single head R2Sonic 2024 MBES, an AML Micro.X for the surface sound speed system, an AML/eTrac MVP-X for the sound speed system, an AML Base.X2 as a spare for the sound speed system, and an Applanix POS MV WaveMaster for the positioning and attitude system. ASV Inez utilized a single head R2Sonic 2022 MBES, an AML Micro.X for the surface sound speed system, and a R2Sonic I2NS for the positioning and attitude system. A beam-to-beam statistical analysis was performed using the Cross Check tool in Qimera. A 4 meter Combined Uncertainty and Bathymetric Estimator (CUBE) weighted dynamic surface was created incorporating only the mainscheme lines and excluded crosslines. The Cross Check tool was used to perform the beam-by-beam comparison of the crossline data to the mainscheme surface. Comparisons showed excellent agreement, well above 95% of the allowable TVU. Note: This surface was created for QC only and is not submitted as a surface deliverable. Below is a histogram of the crossline comparison statistics showing IHO Order 1a compliance per beam. H13694 Crossline Comparison file:///N:/Project%20Files/NOAA_TO06_Nome/REPORTING/_DR/H13694/SupportFiles/H13694_4m_CrossCheck.png ERS via ERTDM 0.13 R/V Norseman II 0.05 0.2 ASV Inez 0.05 0.2 The standard deviation uncertainty and the total vertical uncertainty (TVU) layers of the Dynamic Surface were utilized during data processing to search for features, water column noise, and systematic errors. IHO Order 1a uncertainty specification was met by 100% of the nodes. In Qimera versions beginning in 2.5.1 and beyond, the user has the ability to export the Dynamic Surface to a Bathymetric Attributed Grid (BAG) with the TVU layer. Using this BAG, the percentage of nodes that fell within the TVU specification for each Dynamic Surface was calculated using the NOAA QC tools program.These results are shown in an image below. The TVU was also reviewed using the Colormap Range in the Qimera TVU surface layer. This image is also included below. Set Line Spacing Coverage MBES (Finalized 4m CUBE weighted Dynamic Surface) = 100% of nodes are within the allowable TVU. H13694 Finalized 4m MBES TVU Statistics file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_MB_4m_MLLW_Final_TVU.png No junctions exist for this survey. Sonar system quality control checks were conducted as detailed in the quality control section of the DAPR. None Exist There were no conditions or deficiencies that affected equipment operational effectiveness. None Exist There were no other factors that affected corrections to soundings. SVP casts were generally taken every 2 hours. Occasionally casts would exceed a 2 hour frequency, however would never exceed a 4 hour frequency. On R/V Norseman II casts were applied in QPS Qinsy acquisition software at the time of the cast. Casts taken on R/V Norseman II were shared with ASV Inez and applied in QPS Qinsy at the same time. Surface sound velocity measured at 1Hz was compared to surface velocity from the sound velocity profile in real-time. If the surface velocity comparison was in excess of 2 m/s at any time during survey operations, a new cast was taken. Surface sound speeds were compared in real-time and profile to profile for each cast on the vessel. Additionally, the processor reviewed profiles in Qimera to remove spurious readings within a cast, compare day-to-day casts, and to check distribution over the surveyed area, in order to better understand trends for efficient acquisition planning. All equipment and survey methods were used as detailed in the DAPR. Data Density Evaluation In order to determine if the density of the data met the specified 5 soundings per node, data density was evaluated using DensityTrac in the AmiTrac program, developed in-house by eTrac. Each finalized CUBE weighted dynamic surface's nodes were exported to a BBH file. The BBH file was then loaded into the DensityTrac program and density statistics were computed. For H13694 the following percentages represent the results of the density query: Set Line Spacing Coverage MBES (Finalized 4m CUBE weighted Dynamic Surface) = 99.16% of nodes are composed from at least 5 soundings. H13694 Finalized 4m Set Line Spacing MBES Density Distribution file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_MB_4m_MLLW_Final_Density.png All data reduction procedures conform to those detailed in the DAPR. All sounding systems were calibrated as detailed in the DAPR. Backscatter data were collected throughout the survey and are retained in the raw DB files. Every effort was made in the field to collect quality backscatter data while maintaining the primary mandate of high quality bathymetric data. eTrac verified coverage and general quality of the backscatter data collected daily. A beam intensity window was monitored in Qinsy during acquisition to ensure backscatter data collection. Raw backscatter data were viewed in QPS FMGeocoder (FMGT) to further confirm collection criteria had been met. After MBES data was fully processed and cleaned in Qimera, GSF files were exported and brought into FMGT and processed into backscatter mosaics. Shown below is an example of the raw backscatter mosaic from H13694 DN221 (R/V Norseman II). Raw Backscatter from R/V Norseman II (DN221) file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_DN221_NO_Backscatter.png NOAA Profile Version 2022 Feature Object Catalog, NOAA Profile Version 2022 was used only in CARIS. Qimera was used as the primary processing software. H13694_MB_4m_MLLW_Final BAG 4 15.12 18.54 NOAA_4m MBES Set Line Spacing H13694_MBAB_2m_NO_400kHz_1of2 MB Backscatter Mosaic 2 N/A MBES Set Line Spacing H13694_MBAB_2m_IN_400kHz_2of2 MB Backscatter Mosaic 2 N/A MBES Set Line Spacing A 4m surface is provided meeting Set Line Spacing MBES with backscatter specifications for H13694. H13694 Finalized 4m CUBE weighted Dynamic Surface Coverage file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_SurfaceCoverage_4m.png H13694 Finalized 2m MBAB Mosaic Coverage file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_MosaicCoverage_MBAB.png Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR and DAPR. Mean Lower Low Water ERS via ERTDM OPR-R390-KR-23_Nome_OffshoreHooperBay_AK_ERTDM_2023_NAD83-MLLW.qgfvom In order to reference soundings to Mean Lower Low Water Datum, a separation model was provided by NOAA and was applied to the Qinsy DB files via a .qgfvom separation file in the acquisition software. North American Datum 1983 Projected UTM 3 RTX Applanix PosPac MMS was utilized to post process real time positioning data utilizing Trimble's PP-RTX implementation of Trimble CenterPoint RTX to create a Smoothed Best Estimate of Trajectory (SBET). GNSS satellite corrections were received on each vessel using the G2+ or G4+ carrier signal from the Marinestar Global Correction System maintained by Fugro. A chart comparison was conducted for H13694 using Pydro CA tools, Qimera, and Caris HIPS and SIPS. Survey data were compared against the largest scale ENC to accomplish the chart comparison. The largest scale ENC does not cover the entire survey boundary so two other charts were used to complete the chart comparison. Details of the ENCs used are listed below. US2AK95M, scale: 1534076, edition: 12, update application date: 3/7/2023, issue date: 3/7/2023 Throughout survey operations sounding comparisons between the charted depths and the surveyed depths were analyzed to identify depth discrepancies. Using 4 meter CUBE weighted Dynamic surfaces, soundings were generated in the "Sounding Selection" tab of Pydro CA tools. Soundings were displayed against the charted soundings and a visual comparison was made in Caris HIPS and SIPS. Additionally, potential DtoNs and discrepancies were generated using the "DTM vs Chart" tab of Pydro CA tools. The results were displayed through CA tools and investigated in CARIS HIPS and SIPS and Qimera. An overview image of the generated soundings on each chart is included below. Results of the chart comparison are included in the following sections. Generated Soundings used for Chart Comparison (US2AK95M) file:///M:/OPRR390KR23/Surveys/H13694/01_HDR/Working/DR/H13694_DR/SupportFiles/H13694_ChartComparison_US2AK95M.png US2AK95M 1534076 12 2023-03-07 2023-03-07 No shoals or potentially hazardous features exist for this survey. No charted features were assigned in H13694. No new features were found H13694. No channels exist within the survey limits. No Aids to Navigation (ATONs) exist for this survey. No Maritime Boundary Points were assigned for this survey. 3 bottom samples were obtained in accordance with section 7.1 of the HSSD 2022 in areas designated by the field through discussions with our COR. Detailed information and images of the bottom samples are located in the Final Feature File (FFF). Each bottom sample has been given a unique identifier in the "userid" field of the .000 S-57 file (format BX). 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 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 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 CUBE surfaces, 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 Manual, 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. David Neff, C.H. Chief of Party 2023-12-04