OPR-N338-NRTSE-23 Columbia River, WA and OR Oregon Washington H13847 Bonneville to Drano Lake -0700 2023-09-07 2023-09-16 DOC/NOAA/NOS/OCS -- Office of Coast Survey HSD.Chief@noaa.gov NOAA NRT-Seattle 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). file:///M:/OPR-N338-NRTSE-23/Surveys/H13847/01_HDR/Reports/QC/PI_survey%20area.png file:///M:/OPR-N338-NRTSE-23/Surveys/H13847/01_HDR/Reports/QC/Survey%20Surface.png H13847_MB_VR_CRD_1of1 Projected UTM 10 North American Datum 1983 (2011) arc degree Columbia River Datum meters found by multi beam Yes Yes 1.0m (Critical) N/A Yes Yes No 2m (Critical) N/A 0.25m (Critical) 0.75% (Exceptional/Critical) S3006 NRT Seattle Positioning and Attitude System Applanix POS MV 320 v5 POS MV V5 14128 2023-04-13 Multibeam Kongsberg Maritime EM 2040C EM2040C Processing Unit 2U CZC3440R5X NA 2018-05-02 2023-03-28 Conductivity, Temperature, and Depth Sensor SonTek CastAway-CTD SonTek CC1433007 2023-04-27 2023-04-27 Crossline was not performed for this survey Survey H13847 junctions with H13669. The Pydro 24 tool Compare Grids tool was utilized to assess the overlap of these junctions. The results of these junctions are shown in the final data package. The results between H13847 and H13669 indicate that 85.76% of grid-node comparisons are within Allowable Error Fraction Exceptional standards for depth. The resulting mean of this comparison was 0.07m, with a standard deviation of 0.61m which is within allowable total vertical uncertainty (TVU) for the area. H13847 and H13669 Junction file:///M:/OPR-N338-NRTSE-23/Surveys/H13847/Metadata/QC/H13847_MB_VR_CRD_Final-H13669_MB_VR_CRD_Final_depth_delta_2024.png NRT-SE's primary bathymetric data review and quality control tool is the CARIS CUBE surfaces. The CUBE algorithm generates a surface consisting of multiple hypotheses that represent the possible depths at any given position. The CUBE surface is a grid of estimation nodes where depth values are computed based on the horizontal and vertical uncertainty of each contributing sounding. Any individual sounding’s uncertainty, or Total Propagated Uncertainty (TPU), is derived from the assumed uncertainty in the echosounder measurement itself, as well as the contributing correctors from sound speed, water levels, position, and attitude. TPU values for tide and sound velocity must be entered for each vessel during TPU computation, unless using TCARI, where uncertainty is added directly to survey lines by Pydro. NRT-SE is currently using the following uncertainty values: GPS tide uncertainty is unique to the separation model in use. Measured sound speed uncertainty was set to a recommended value of 2 m/s as recommended by the FPM when 1 cast is taken every 4 hours. Surface sound speed value is dependent on the manufacturer specifications of the unit utilized to measure surface SV values for refraction corrections to flat-faced transducers. The AML Oceanographic Micro-X probe with an SV-Xchange sensor has a published accuracy of 0.025 m/s, however, a value of 0.2 m/s is used for surface sound speed uncertainty. All other error estimates are read from the Hydrographic Vessel File (HVF). The HVF contains all offsets and system biases for the survey vessel and its systems, as well as error estimates for latency, sensor offset measurements, attitude and navigation measurements, and draft measurements. In addition, the HVF specifies which type of sonar system the vessel is using. In addition to the usual a priori estimates of uncertainty, some real-time and post-processed uncertainty sources were also incorporated into the depth estimates. Real-time uncertainties from the Kongsberg EM2040C were recorded and applied in post-processing. Applanix TrueHeave files are recorded, which include an estimate of the heave uncertainty, and are applied during post processing. Uncertainties associated with vessel roll, pitch, gyro, and navigation are applied in CARIS HIPS and SIPS via a SBET and RMS files generated in POSPac. The Grid QA tool within QC Tools was used to analyze data density and uncertainty of gridded data. The finalized VR surface was analyzed using the Pydro QC Tools Grid QA feature to determine compliance with specifications. Density requirements for H13847 were achieved with at least 99.5+% of surface nodes containing five or more soundings as required by HSSD Section 6.9. The surface was analyzed using the HydrOffice QC Tools Grid QA feature to determine compliance with specifications. Overall, 99.5+% of nodes within the surface meet NOAA Allowable Uncertainty specifications for H13847. Pydro derived plot showing percent of nodes in compliance with HSSD standards for H13847 VR surface file:///M:/OPR-N338-NRTSE-23/Surveys/H13847/Metadata/QC/H13847_MB_VR_CRD_Final.QAv7.density.png Pydro derived plot showing TVU compliance of H13847 VR surface file:///M:/OPR-N338-NRTSE-23/Surveys/H13847/Metadata/QC/H13847_MB_VR_CRD_Final.QAv7.tvu_qc.gn1.png The CUBE surface child layers: uncertainty, standard deviation, and node standard deviation were primarily used to help focus directed editing to soundings that were negatively affecting the BASE surface. Another method to check the quality of sounding data prior to submission is the Pydro QC Tools “Flier Finder.” This software scans the CUBE surface for potential anomalous grid data. Lowering the flier height value will increase the sensitivity of the flier finder, resulting in more nodes being flagged. Fliers are then exported as .000 S-57 files that can be imported into CARIS HIPS and SIPS to aid in further cleaning. If desired, the user can set a new tolerance (“Flier height”) and rerun Flier finder. On occasion, the resolution of the CUBE surface may not be sufficient to capture the high point of a feature. In less than 20 m of water, any feature where the most probable accurate sounding is shoaler than the CUBE surface by greater than one half the allowable error OCS Quality Metrics for Uncertainty is considered inadequately captured by the CUBE surface. In greater than 20m of water, this allowable error is expanded to the full OCS Quality Metric error allowance at that depth. Although missed shoal points may occur on irregular shoals or rock pinnacles, man-made features such as piles and wrecks are of particular concern. These features have very slender high points that extend far above the surrounding seafloor as well as the CUBE surface. To ensure that these features are properly represented, the shoalest point is flagged “designated” in CARIS. During the “finalization” process, the CUBE surface is forced to honor all soundings which have been flagged “designated.” In the case of a survey where the high points of many features (i.e. a boulder field) are not being captured by the CUBE surface, the hydrographer may decide to produce higher resolution CUBE surfaces to ensure that these features are being honored. Most holidays are identified and addressed while in the field. During data acquisition, the display of the real-time swath coverage is based upon the matrix file, a polygon with user-defined geographic bounds and resolution set up prior to data collection. The resolution of the matrix is selected to match depth range of the polygon currently being worked on. The launch coxswain uses this matrix display to adjust the line as it is driven so that the swath currently being collected overlaps the grid of previously collected data. In this way, insufficient overlap can be seen and addressed immediately. Due to equipment failure, some holidays were unable to be addressed while in the field and and are shown within the data. The Pydro QC Tools "Holiday Finder" is used to detect holidays in post-processing. This tool scans the grid, and any empty nodes surrounded by populated nodes are identified and was run in conjunction with a visual inspection of all surfaces by the hydrographer. The user can specify whether to search for holidays according NOAA HSSD. In the event of finding any holidays in post-processing, small polygons are made in HIPS to direct data acquisition to fill them in. Holiday Finder identified 48 holidays for H13847_MB_VR_CRD_Final. These data are adequate to supersede charted data in their common areas. Imagery coverage assessment was not performed for this survey Data interpolation was not performed for this survey N/A MBES frequency and settings remained unchanged throughout the survey area. Swath width was manually decreased in shallow water to mitigate edge fliers. N/A N/A Kongsberg EM2040C stores the raw backscatter data in the .all file. Raw MBES backscatter was logged as part of the .all file of the Kongsberg EM2040 systems. Backscatter was processed in QPS Fledermaus GeoCoder Toolbox (FMGT) software, and the exported geotiffs are included in the final processed data package. 2025-0-00 Total Propagated Uncertainty (TPU) values for H13847 were derived from a combination of fixed values for equipment and vessel characteristics, as well as field assigned values for sound speed uncertainties. The uncertainty for the VDatum model was provided to the field units. In addition to the usual a prior estimates of uncertainty, some real time and post processed uncertainty sources were also incorporated into the depth estimates of the survey. Real-time uncertainties from the Kongsberg MBES sonars were incorporated and applied during post processing. Uncertainties associated with vessel roll, pitch, gyro, navigation, and heave were applied during post-processing. All of the aforementioned uncertainties were applied in CARIS. As stated, H13847 is an ellipsoidally referenced survey (ERS) and the tidal component was accomplished with a separation model. There are two places in CARIS where the user directly defines uncertainty values for use in CARIS to calculate TPU values, in the HVF and the direct input of SV and GPS model values during the TPU computation. TPU values for all motion, navigation position and timing values are taken directly from Appendix IV (Uncertainty values for use in CARIS with vessels equipped WITH an attitude sensor) of the FPM. All timing values were set to 0.001 seconds as outlined for setups with Ethernet connections and precise timing. All offset values were chosen to be 0.02 meters based on the accuracy provided by professional surveys. All MRU alignment values are derived from the patch test. The gyro value is taken directly from the standard deviation of the yaw . Data gaps exist within the survey as the team did not return to the field post equipment failures. The area is highly changeable with sand waves throughout the area increased the probability of offsets for returning at a later date. Sea grass is present throughout the survey grounds and has been filtered out of the data, however some sea grass may remain. The removal of sea grass has left areas of tracklines where no bathymetric coverage exists and has been indicated in the feature file. In certain areas the coastline should be reviewed based on data collected. Issues with .bag file checks may be flagged due to designated soundings within the data and is a known issue. One assigned rock feature was unable to have least depth known collected due to covering/ uncovering nature, making it a hazard to proceed with data collection in the area. The Navigation Response Branch Chief received authorization from the Pacific Hydrographic Branch to submit H13847 in accordance with the HSSD 2024 on April 18, 2024. The Project Instructions stated that object detection acquisition was required for assigned priority areas as safe operations permitted and complete coverage elsewhere in H13847. H13847 was processed to Critical specifications for priority areas and General 1 specifications for elsewhere. Final Survey Outline 2024-08-14 NCEI Sound Speed Data 2024-08-13 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 and approved all data and metadata. The survey meets or exceeds requirements as set forth in the Project Instructions and NOS Hydrographic Surveys Specifications and Deliverables. The survey is complete and no additional work is required with the exception of any deficiencies noted in the Report of Survey. LTJG Ashley Howell Chief of Party