OPR-L397-FA-19Channel Islands National Marine SanctuaryChannel Islands, CANOAA Ship FAIRWEATHERH132081Posa Anchorage to Fraser PointCaliforniaUnited States200002019CAPT Marc MoserNavigable Area2019-08-272019-10-122019-10-14Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUTCPacific 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/.NOAAThe survey area is located between Posa Anchorage and Fraser Point, CA34.059167119.9740733.980478119.874856H13208 sheet limits (in blue) overlaid onto Chart 18728SupportFiles\H13208_Sheet_Limits.jpgData were acquired to the survey limits in accordance with the requirements in the Project Instructions and the March 2019 NOS Hydrographic Surveys Specifications and Deliverables (HSSD) as shown in Figure 1. In all areas where the 3.5 meter depth contour or the sheet limits were not met, the Navigable Area Limit Line (NALL) was defined as the inshore limit of bathymetry due to kelp, the risks of maneuvering around anchored vessels, or in close proximity to the steep and rocky shoreline. An example of such an area is shown in Figure 2.
Areas where the NALL was defined by the presence of kelp or the risks of maneuvering around anchored vessels and the steep and rocky shoreline.SupportFiles\H13208_survey_limits.jpgThis year the Channel Islands National Marine Sanctuary work will focus on the remaining survey area around Santa Cruz Island, the largest of the Channel Islands (about 97 sq. mi.), located about 30 miles offshore of the California mainland city of Santa Barbara. The waters surrounding CINMS are highly productive and are home to recreational and commercial fishing efforts, and regularly host kayakers, surfers, sightseers, whale watchers, researchers, and Channel Islands National Park concessionaires, who all access the sanctuary via boats. Correspondingly, the abundance of sea life and aquatic habitats drives a thriving industry of recreational and commercial fishing that brings varied vessel traffic through the waters of CINMS. The commercial fishing vessel traffic alone is responsible for the highest commercial landings value (approximately $450 million; 2005-2015) across all of California’s ports. Additionally, major mainland port traffic transiting to and from Los Angeles and Long Beach, California routes large cargo and tanker vessels close to CINMS boundaries. Much of the existing nautical chart data dates back to 1930s lead line or single beam echo sounder surveys, and the areas not surveyed to modern standards are predominantly located in the shallow waters (<40m) where vessel traffic is highest. This poses a serious risk to life, property, and the delicate ecosystem with 64 groundings since 2000. Increasing traffic is increasing the risk, with seven of those groundings in 2015 alone. Modern survey efforts, such as a 2015 survey by NOAA Ship Bell M. Shimada, have found previously undetected pinnacles within the sanctuary. This survey will continue modern mapping efforts to identify any similar threats that may exist in these waters. The CINMS hydrographic survey will be as unique as the region itself. In addition to providing data for crucial nautical chart updates, this survey will also generate backscatter data, which will be used in habitat mapping and substrate analysis. Both multibeam echo sounder and backscatter data will not only serve to enhance marine navigational safety, but will also be used by sanctuary managers, planners, and researchers, aiding them in the conservation of this most precious resource. 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. Data acquired in H13208 meet multibeam echo sounder (MBES) coverage requirements for complete coverage, as required by the HSSD. This includes crosslines (see Section B.2.1), NOAA allowable uncertainty (see Section B.2.09), and density requirements (see Section B.2.10).All waters in survey areaComplete CoverageThe entirety of H13208 was acquired with Complete Coverage, meeting the requirements listed above and in the HSSD. See Figure 3 for an overview of coverage.H13208 survey coverage overlaid onto Chart 18728SupportFiles\H13208_coverage_overview.jpg28070116.72000005.5002806062.26000000.8102805061.44000000028080110.12000009.2600350.540000015.5700000015.092019-10-122019-10-132019-10-14Refer to the OPR-L397-FA-19 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.28058.61.128088.61.128068.61.128078.61.1Kongsberg MaritimeEM 2040MBESSea-Bird ScientificSBE 19plus V2Conductivity, Temperature, and Depth SensorApplanixPOS MV 320 v5Positioning and Attitude SystemTeledyne RESONSVP 71Sound Speed SystemThe equipment was installed on the survey platform as follows: Each launch utilizes the Kongsberg EM 2040 MBES, a POS MV v5 system for position and attitude, SVP 71 surface sound speed sensors, and SBE 19plus V2 for conductivity, temperature, and depth (CTD) casts.
Crosslines were collected, processed and compared in accordance with Section 5.2.4.2 of the HSSD. To evaluate crosslines, a surface generated via data strictly from mainscheme lines and a surface generated via data strictly from crosslines were created. From these two surfaces, a difference surface (mainscheme - crosslines = difference surface) was generated (Figure 4), and is submitted in the Separates II Digital Data folder. Statistics show the mean difference between depths derived from mainscheme data and crossline data was 0.02 meters (with mainscheme being shoaler) and 95% of nodes falling within +/- 0.26 meters (Figure 5). For the respective depths, the difference surface was compared to the allowable NOAA uncertainty standards. In total, 99.93% of the depth differences between H13208 mainscheme and crossline data were within allowable NOAA uncertainties.Overview of H13208 crosslinesSupportFiles\H13208_crossline_comparison.jpgH13208 Crossline and maincheme difference statisticsSupportFiles\H13208_Crossline_statistics.jpg7.8ERS via VDATUM280X20.5In addition to the usual a priori estimates of uncertainty via device models for vessel motion and VDATUM, real-time and post-processed uncertainty sources were also incorporated into the depth estimates of survey H13208. Real-time uncertainties were provided via EM 2040 MBES data and Applanix Delayed Heave RMS. Following post-processing of the real-time vessel motion, recomputed uncertainties of vessel roll, pitch, gyro and navigation were applied in CARIS HIPS and SIPS via a Smoothed Best Estimate of Trajectory (SBET) RMS file generated in Applanix POSPac.H13208 junctions with 2 adjacent surveys from this project, H13209, H13325 and 1 survey from prior projects, H13205 as shown in Figure 6. Data overlap between H13208 and each adjacent survey was achieved. These areas of overlap between surveys were reviewed in CARIS HIPS and SIPS by surface differencing (at equal resolutions) to assess surface agreement. The multibeam data were also examined in CARIS Subset Editor for consistency and agreement. The junctions with H13208 are generally within the NOAA allowable uncertainty in their areas of overlap. For all junctions with H13208, a negative difference indicates H13208 was shoaler and a positive difference indicates H13208 was deeper.Overview of H13208 junction surveysSupportFiles\H13208_junction_overview.jpgH13209200002019NOAA Ship FAIRWEATHERNSurface differencing in CARIS HIPS and SIPS was used to assess junction agreement between the surface from H13208 and the surface from H13209 (Figure 7). The statistical analysis of the difference surface shows a mean of 0.05 meters with 95% of the nodes having a maximum deviation of +/- 0.34 meters, as seen in Figure 8. It was found that 99.85% of nodes are within NOAA allowable uncertainty.Difference surface between H13208 (gray) and junctioning survey H13209 (brown)SupportFiles\H13208_H13209_junction_difference.jpgDifference surface statistics between H13208 and H13209 (VR surface)SupportFiles\H13208_H13209_junction_stats.jpgH13325200002019NOAA Ship FAIRWEATHERSESurface differencing in CARIS HIPS and SIPS was used to assess junction agreement between the surface from H13208 and the surface from H13325 (Figure 9). The statistical analysis of the difference surface shows a mean of 0.04 meters with 95% of the nodes having a maximum deviation of +/- 0.17 meters, as seen in Figure 10. It was found that 99.99% of nodes are within NOAA allowable uncertainty.Difference surface between H13208 (gray) and junctioning survey H13325 (purple)SupportFiles\H13208_H13325_junction_difference.JPG
Difference surface statistics between H13208 and H13325 (VR surface)SupportFiles\H13208_H13325_junction_stats.JPGH13205200002018NOAA Ship RAINIERWSurface differencing in CARIS HIPS and SIPS was used to assess junction agreement between the surface from H13208 and the surface from H13205 (Figure 11). The statistical analysis of the difference surface shows a mean of 0.11 meters with 95% of the nodes having a maximum deviation of +/- 0.32 meters, as seen in Figure 12. It was found that 99.97% of nodes are within NOAA allowable uncertainty.Difference surface between H13208 (gray) and junctioning survey H13205 (pink)SupportFiles\H13208_H13205_junction_difference.JPGDifference surface statistics between H13208 and H13205 (VR surface)SupportFiles\H13208_H13205_junction_stats.JPGSonar system quality control checks were conducted as detailed in the quality control section of the DAPR.None ExistThere were no conditions or deficiencies that affected equipment operational effectiveness.Sound Speed IssuesIn certain areas, particularly the central and southern offshore portions of the survey area, sound speed issues were apparent, visible primarily as "smiles" (see Figure 13). Given the location of the issues, the most probable cause is subsurface mixing that was not modeled on the surface. Surfaces were not significantly impacted and the data still meet NOAA allowable uncertainty parameters from HSSD Section 5.1.3. As such, the data remain sufficient to supersede previous data.Example of sound speed issues visible in the data exaggerated 20xSupportFiles\H13208_sound_speed_issues.JPGCasts were conducted at a minimum of one every four hours during launch acquisition. Casts were conducted more frequently in areas where the influx of freshwater had an effect on the speed of sound in the water column and when there was a change in surface sound speed greater than two meters per second. All equipment and survey methods were used as detailed in the DAPR.NOAA Allowable UncertaintyThe surface was analyzed using the HydrOffice QC Tools Grid QA feature to determine compliance with specifications. Overall, 99.99% of nodes within the surface meet NOAA Allowable Uncertainty specifications for H13208 (Figure 14).H13208 Allowable uncertainty statisticsSupportFiles\H13208_QA_uncertainty.JPGDensityThe surface was analyzed using the HydrOffice QC Tools Grid QA feature to determine compliance with specifications. Density requirements for H13208 were achieved with at least 99.89% of surface nodes containing five or more soundings as required by HSSD Section 5.2.2.3 (Figure 15).H13208 Data density statisticsSupportFiles\H13208_QA_data_density.JPGAll data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Raw backscatter data were stored in the .all file for Kongsberg systems. All backscatter were processed to GSF files and a floating point mosaic was created by the field unit via Fledermaus FMGT 7.8.10. See Figure 16 for a greyscale representation of the complete mosaic. A relative backscatter calibration was performed by HSTB via a patch test in order to bring the survey systems on each of the launches into alignment. See Figure 17 for a table of the calibration values entered into the Processing Settings within FMGT. Approximate inter-calibration corrections for offsets between sonar systems were applied to the mosaic.Backscatter mosaic for H13208SupportFiles\H13208_backscatter.jpgBackscatter calibration valuesSupportFiles\H13208_backscatter_calibration.JPGCARISHIPS and SIPS11.1.3QPSFledermaus7.8.10NOAA Profile Version 2019H13208_MB_VR_MLLW_finalCARIS VR Surface (CUBE)Variable Resolution0.543173.218NOAA_VRComplete MBESH13208_MB_VR_MLLWCARIS VR Surface (CUBE)Variable Resolution0.543173.218NOAA_VRComplete MBESThe NOAA CUBE parameters defined in the HSSD were used for the creation of all CUBE surfaces for H13208. The surfaces have been reviewed where noisy data, or "fliers" are incorporated into the gridded solutions causing the surface to be shoaler or deeper than the true sea floor. Where these spurious soundings cause the gridded surface to vary from the reliably measured seabed by greater than the maximum allowable Total Vertical Uncertainty at that depth, the noisy data have been rejected by the hydrographer and the surface recomputed.
Flier Finder, part of the QC Tools package within HydrOffice, was used to assist the search for spurious soundings following gross cleaning. Flier Finder was run iteratively until all remaining flagged fliers were deemed to be valid aspects of the surface.
Data LogsData acquisition and processing notes are included in the acquisition and processing logs, and additional processing such as final separation model reduction and sound speed application are noted in the H13208 Data Log spreadsheet. All data logs are submitted digitally in the Separates I folder.Per Section 5.1.2.3 of the 2014 Field Procedures Manual, no Horizontal and Vertical Control Report has been generated for H13208.Mean Lower Low WaterERS via VDATUMOPR-L397-FA-19_100mNAD83-MLLW_geoid12a.csarERS methods were used as the final means of reducing H13208 to MLLW for submission.North American Datum 1983Projected UTM 11RTXVessel kinematic data were post-processed using Applanix POSPac processing software and RTX positioning methods described in the DAPR. Smoothed Best Estimate of Trajectory (SBET) and associated error (RMS) data were applied to all MBES data in CARIS HIPS and SIPS.During real-time acquisition, all platforms received correctors from the Wide Area Augmentation System (WAAS) for increased accuracies similar to USCG DGPS stations. WAAS and SBETs were the sole methods of positioning for H13208 as no DGPS stations were available for real-time horizontal control.A comparison was performed between survey H13208 and ENC US5CA66M using CARIS HIPS and SIPS. Sounding and contour layers were overlaid on the ENC to assess differences between the surveyed soundings and charted depths. The ENC was compared to the surface by extracting all soundings from the chart and creating an interpolated TIN surface which could be differenced with the surface from H13208 as shown in Figure 18. Statistical analysis of the difference surface is shown in Figure 19.
All data from H13208 should supersede charted data. In general, surveyed soundings agree with the majority of charted depths. A full discussion follows below.
US5CA66M4000062019-05-242019-10-04falseSoundings from H13208 are in general agreement with charted depths on ENC US5CA66M with the exception of the southwest corner of the survey area where differences range to 15 fathoms as seen in Figure 20.
Contours from H13208 are in general agreement with charted contours on ENC US5CA66M as shown in Figure 21. The hydrographer recommends that the 20 fathom contour line be updated to represent the most recent survey.Difference surface between H13208 and interpolated TIN surface from ENC US5CA66MSupportFiles\H13208_ENC_difference.jpgDifference surface statistics between H13208 and interpolated TIN surface from ENC US5CA66MSupportFiles\H13208_ENC_difference_stats.jpegOverview of H13208 soundings (fathoms) overlaid onto ENC US5CA66MSupportFiles\H13208_sounding_comparison.JPGOverview of H13208 contours overlaid onto ENC US5CA66MSupportFiles\H13208_contour_comparison.JPGNo Maritime Boundary Points were assigned for this survey.No charted features exist for this survey. Survey H13208 has 12 new features that are addressed in the H13208 Final Feature File. Of these features, there is 1 new Obstruction, 3 new Land Areas, 3 Land Elevations, 4 new Seabed Areas, and 1 new Kelp feature.No shoals or potentially hazardous features exist for this survey.No channels exist for this survey. There are no designated anchorages, precautionary areas, safety fairways, traffic separation schemes, pilot boarding areas, or channel and range lines within the survey limits.No bottom samples were required for this survey.Fairweather personnel conducted limited shoreline verification and reconnaissance, utilizing traditional shoreline methods, at times near predicted negative or low tides within the survey limits. Inaccessible features inshore of the NALL were attributed in the Final Feature File with the description of “Not Addressed” and remarks of “Retain as charted, not investigated due to being inshore of NALL” as per HSSD Section 7.3.1. Annotations, information, and diagrams collected on DP forms and boat sheets during field operations were scanned and included in the Separates I Detached Positions folder. Shoreline verification procedures for H13208 conform to those detailed in the DAPR. No Aids to navigation (ATONs) exist for this survey.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 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.CAPT. Marc MoserChief of Party2020-01-21Lt. Steve MoultonOperations Officer2020-01-21ACHST Alissa JohnsonChief Survey Technician2020-01-27HAST Kevin LallySheet Manager2020-01-21