All equipment and survey methods were used as detailed in the DAPR.42 sound speed profiles were acquired for this survey at discrete locations within the survey area at least once every four hours, when significant changes to surface sound speed were observed, or when operating in a new area. For MBES operations from S221, sound speed profiles were acquired using the Odim Brooke Ocean MVP200. Launch sound speed profiles were acquired using Sea-Bird 19plus SEACAT Profilers. All casts were concatenated into a master file and applied using the "Nearest distance within time" (4 hours) profile selection method with the following exceptions: S221 DN304 survey lines were sound speed corrected using file 2804_DN304_Concat.svp due to pronounced sound speed artifacts in the data when the master concatenated file was used. A similar issue with 2802 DN294 MBES lines was corrected by post-processing sound speed data using only the casts acquired by that boat on that day. The issue with the master concatenated file may be related to the inclusion of ship casts and the apparent thinning of the MVP200 profiles that occurs during processing. Application of the individual launch profiles mentioned above, greatly reduced the artifacts; all examined sound speed related offsets were observed to be within the NOAA HSSD standards.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_SoundSpeedCasts.jpgH13093 sound speed cast locations.Due to the emphasis on acquiring high quality and consistent backscatter for this project, the Kongsberg EM2040 sonar systems were operated in fixed pulse length settings. Kongsberg SIS software was manually set to "Long" or "Short" pulse lengths by the Hydrographer-in-Charge. Generally, "Long" pulse length was selected unless the vessel would be working in waters less than 20 meters deep for extended periods, in which case "Short," would be selected. Operating in this manner created far fewer changes in pulse length compared to running the sonar in "Auto" mode. Fewer changes in pulse length creates more consistent backscatter imagery and requires less post-processing adjustment to intensity levels. The field unit carefully monitored the quality of bathymetry to ensure that the negative impacts of a set pulse length were minimal.Sonar Settings Optimized for Backscatter AcquisitionSonar system quality control checks were conducted as detailed in the quality control section of the DAPR.28.4 nautical miles of multibeam crosslines were acquired by RAINIER launches 2802 and 2804 across all depth ranges, water masses and boat days that were operationally practical. The Hydrographer deems them adequate for verifying and evaluating the internal consistency of H13093 survey data. Analysis was performed using the Compare Grids function in Pydro Explorer on 4-meter resolution surfaces of H13093 mainscheme only and crossline only data. 99.5+% of nodes met allowable uncertainties, for additional results, see figures 6-9 below.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_Crosslines.jpgH13093 crossline surface overlaid on mainscheme tracklines.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_MS_Only_4m-H13093_XLs_Only_4m_fracAllowErr_Freq.pngPydro derived plot showing percentage-pass value of H13093 mainscheme to crossline data.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_MS_Only_4m-H13093_XLs_Only_4m_depth_delta.pngPydro derived plot showing absolute difference statistics of H13093 mainscheme to crossline data.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_MS_Only_4m-H13093_XLs_Only_4m_fracAllowErr_vsDepth.pngPydro derived plot showing node depth vs. allowable error fraction of H13093 mainscheme to crossline data.H13093 junctions with the priority 3 area of survey W00343, a habitat mapping project conducted by NOAA Ship Reuben Lasker in 2016.The junction with survey W00343 encompassed 0.44 square nautical miles along the southwestern boundary of H13093. A comparison was made with the Compare Grids function of Pydro Explorer using a difference surface derived from 4-meter Caris .csar surfaces of each survey. Analysis of the difference surface indicated that H13093 is an average of 5.0 meters deeper than W00343 with a standard deviation of 2.02 meters. According to the Survey Acceptance Review (SAR) issued by the Pacific Hydrographic Branch, W00343 was a habitat mapping survey acquired with a Simrad ME70, a sonar normally used to collect water column data for fisheries applications. The SAR also stated that data from the ME70 are not suitable for object detection, feature disproval or for areas of critical under-keel clearance. The W00343 SAR identified persistent heave-like artifacts throughout the entire survey, the lack of crosslines and that the survey was significantly shoaler (5.9 meters) than junction survey W00291. This information helps to explain the poor comparison between H13093 and W00343 data. H13093 was acquired under significantly higher data quality standards than was W00343 and should be considered the more accurate of the two.SWNOAA Ship Reuben LaskerW00343201640000file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_Diff_W00343_4m.jpgH13093 / W00343 junction difference surface.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_MB_4m_MLLW-Priority3_MB_4m_MLLW_Office_depth_delta.pngPydro derived plot showing H13093 / W00343 comparison statistics.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_W00343_Junction.jpgH13093 / W00343 Junction.Due to water column variations such as thermal layering and salinity differences, a distinct demarcation of water masses was sometimes encountered in the field. At times, this proved problematic in the acquisition and application of optimal sound speed correction data. Despite the best efforts of the hydrographers to conduct sufficient sound speed casts distributed spatially and temporally, in some areas, particularly in the northern part of the survey, sound speed correction was suboptimal. This was evidenced by the appearance of systematic artifacts in the survey grid and the characteristic "smiles" or "frowns" of the data when viewed in subset editor. To address this issue, the Hydrographer rejected outer beam soundings obviously in error in an attempt to produce a surface that best represented the sea floor. All examined sound speed related offsets were observed to be within NOAA HSSD standards.Suboptimal Sound Speed Correctionfile:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/SV_Issue.jpgExample of area with suboptimal sound speed correction. Inset shows subset view with rejected sounding colored grey.Total Propagated Uncertainty (TPU) values for survey H13093 were derived from a combination of fixed values for equipment and vessel characteristics, as well as from field assigned values for sound speed uncertainties. Tidal uncertainty was provided in the metadata accompanying the NOAA vertical datum transformation model used for this survey. The local VDATUM model uncertainty of 0.082867 meters was entered as the tide zoning value for TPU calculation. 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 of this survey. Real-time uncertainties from Kongsberg MBES sonars were recorded and applied in post-processing. Applanix TrueHeave (POS) files, which record estimates of heave uncertainty, were applied during post-processing. Finally, the post-processed uncertainties associated with vessel roll, pitch, yaw and position were applied in Caris HIPS using SBET and RMS files generated using POSPac MMS software. Uncertainty values of the submitted finalized grid was calculated in Caris using "Greater of the Two" of uncertainty and standard deviation (scaled to 95%). Grid QA v5 within Pydro QC Tools 2 was used to analyze H13093 TVU compliance, a histogram plot of the results is shown below.30.152801,2802,2803,28040.051S2210.082867ERS via VDATUM0file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_MB_VR_MLLW_Final.QAv5.tvu_qc.pngPydro derived plot showing TVU compliance of H13093 finalized multi-resolution MBES data.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.All data for H13093 were acquired by NOAA Ship RAINIER and survey launches 2801, 2802, 2803, and 2804. The vessels acquired depth soundings, backscatter imagery and sound speed profiles. Shoreline feature verification was conducted from RAINIER skiffs 1905 and 1907.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/S221_Anacapa.jpgNOAA Ship RAINIER anchored near East Anacapa Island.4.770.4S2211.18.828011.18.828021.18.828031.18.828040.355.719050.355.71907Refer to the Data Acquisition and Processing Report (DAPR) for a comprehensive description of data acquisition and processing systems, survey vessels, quality control procedures and data processing methods. Additional information to supplement sounding and other survey data and any deviations from the DAPR are discussed in this report.POS M/V v5ApplanixPositioning and Attitude SystemEM 2040KongsbergMBESEM710KongsbergMBESSVP70 / SVP71ResonSurface Sound Speed ProbesSBE 19plus SEACAT ProfilerSea-Bird ElectronicsConductivity, Temperature, and Depth SensorMVP200 Moving Vessel ProfilerOdim Brooke OceanSound Speed SystemRaw Backscatter was acquired as .all files logged during MBES operations and subsequently processed by personnel aboard Rainier. One mosaic per vessel per frequency has been delivered with this report. All backscatter processing procedures utilized follow those 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.Submitted surfaces were generated using the recommended parameters for depth-based (Ranges) Caris variable-resolution bathymetric grids as specified in HSTD 2017-2. The resolution values indicated in the above table are not accurate: the XML-DR schema used to generate this report did not accommodate variable-resolution grids. The "999" value was entered merely as a place holder. Three critical soundings were created for this survey; all were identified as Dangers to Navigation.Complete MBES999H13093_MB_VR_MLLWCUBE0.87219.69VRComplete MBES999H13093_MB_VR_MLLW_FinalCUBE0.87219.69VRNOAA Extended Attribute File V_5_6.The Wide Area Augmentation System (WAAS) was used for real-time horizontal control for this survey. OPR-L397-RA-17_VDatumArea_xyNAD83-MLLW_geoid12b.csarERS via VDATUM2017-11-172017-11-08H13093 shoreline features were tide corrected using a .tid file created in Pydro utilizing the "TCARI TID file via S-57" function then loaded in Caris Notebook. H13093 MBES data were reduced to MLLW using ERS via VDATUM processing methods.TCARIL397RA2017Rev.tcFinalH13093_TCARI_Features.tidFinal Approved9410840Santa Monica9411340Santa Barbara9411406Oil Platform Harvest9410660Los Angeles9412110Port San Luis9413450MontereyMean Lower Low WaterAdditional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Precise Positioning-Real Time Extended (PP-RTX) processing methods were used in Applanix POSPac MMS 8.1 software to produce SBETs for post-processing horizontal correction.SBET Processing MethodUniversal Transverse Mercator (UTM) Zone 11 NorthNorth American Datum of 1983 (NAD83)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.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.Commanding Officer2018-01-10Benjamin K. Evans, CDR/NOAAField Operations Officer2018-01-10Scott E. Broo, LT/NOAAChief Survey Technician2018-01-10James B. JacobsonSenior Survey Technician2018-01-10B.D. JacksonNo present or planned construction or dredging are known to exist within the survey limits.No platforms exist within the H13093 survey area.Limited shoreline verification was conducted in accordance with applicable sections of NOAA HSSD and FPM using the Project Reference File (PRF) and Composite Source File (CSF) provided with the Project Instructions. In the field, all assigned features that were safe to approach, were addressed as required with S-57 attribution and recorded in the H13093_Final_Feature_File (FFF) to best represent the features at chart scale. This file also includes new features found in the field as well as recommendations to update, retain or delete assigned features. The provided shoreline from the CSF around Anacapa Island, particularly the eastern end, was observed to deviate significantly from the actual coastline as well as from the acquired shoreline data. When physically possible, offshore features were re-positioned in the field, however the shoreline skiffs lacked the equipment to make corrections to Anacapa Island's entire coastline. As a check after the fact, the Hydrographer downloaded vector data from the NGS NOAA Shoreline Data Explorer website; it showed good agreement with H13093 hydrographic and shoreline data of the common area. The Hydrographer recommends that the ENC be updated with the much more accurate NGS shoreline.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/Shoreline%20shift.jpgAn example of poor CSF shoreline at the eastern end of Anacapa Island (CSF shoreline is black with red rejected, NGS shoreline is green). Block “A” includes a new pier that is positioned inshore of the charted CSF shoreline but matches up well with the NGS shoreline. Block “B” includes 2 islets and a rock that were repositioned ~40-50m to the northwest, a new position that matches well with the NGS shoreline.No new surveys or further investigations are recommended for this area.No overhead features were observed within the H13093 survey area.No new insets are recommended for this area.No ferry routes or terminals exist within the H13093 survey area.No prior survey comparisons were provided for this survey.No Aids to Navigation (ATON) were specifically assigned for this survey. The Anacapa Island Light was visually verified and appeared to be serving its intended purpose.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/Anacapa_Island_Light2.jpgAnacapa Island Light.H13093 MBES data revealed a strikingly dynamic seafloor to the southwest of West Anacapa Island. The vertical relief of the swirling ridges measure up to approximately 6 meters high.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_Cool_Swirl.jpgH13093 dynamic seafloor topography.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_Cool_Swirl_Inset.jpgSubset view of dynamic H13093 seafloor area.No charted submarine features exist within the H13093 survey area.A comparison was made between H13093 survey data and Electronic Navigational Charts (ENC) US5CA67M and US5CA58M using CUBE surfaces, selected soundings and contours created in Caris. A positional offset between the two ENCs was identified at the junction of these charts at the east end of the H13093 survey area (Figure 16).file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/ENC_Discontinuity.jpgENC Discontinuity. Red circles identify areas with positional offsets between the ENCs of approximately 75 to 125 meters within the H13093 survey area.No Maritime Boundary Points were assigned for this survey.H13093 is located approximately one half nautical mile south of the South-Eastbound Traffic Lane within the Santa Barbara Channel. There are no charted features with the label PA, ED, PD or Rep within the H13093 survey area.There was no bottom sample requirement for this survey and none were taken.US5CA67M2017-08-244false2017-11-0940000ENC US5CA67M covers all of survey H13093 with the exception of an area approximately 1200 x 1200 meters at the eastern edge of the assigned sheet (Figure 17). A comparison between H13093 derived contours and ENC US5CA67M revealed the following: Three fathom depth contour data from the ENC and H13093 is incomplete, especially around West Anacapa Island, however where a comparison was possible, the agreement was generally good (Figure 18). The ENC 5-fathom depth contour data is incomplete; large gaps exist especially on the north side of West and East Anacapa Island. Where comparison was possible, offsets of approximately 50 meters were common. At the south side of West Anacapa Island, H13093 data identified several 5-fathom depth contours that are uncharted on the ENC; they are approximately 200 meters offshore of the existing ENC 5-fathom depth contour (Figure 19). The ENC 10-fathom depth contour agreed well or was approximately 50 meters offshore of the H13093 derived locations. H13093 data revealed a 15-fathom shoal area seaward of the ENC charted 20-fathom depth contour and is surrounded by deeper depths (Figure 20).file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/ENC_US5CA67M_H13093_Outline.jpgSection of ENC US5CA67M overlaid with H13093 survey outline. ENC US5CA58M joins to the east.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/3_fathom_Depth_Contour_Detail.jpgSection of ENC US5CA67M showing comparison between 3-fathom depth contours from the ENC (in blue) and H13093 (in red) data.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/5_fathom_Depth_Contour_Detai_text.jpgSection of ENC US5CA67M showing comparison between 5-fathom depth contours from the ENC (in blue) and H13093 (in green) data including previously uncharted offshore 5-fathom depths.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/ShoalerThanSurroundingDepths.jpgH13093 15-fathom soundings seaward of charted 20 fathom contour.US5CA58M2017-08-2410false2017-11-1520000H13093 survey soundings and ENC depths agree to within approximately 1 fathom in the common area.No new navigationally significant features were detected that were not included in the H13093 Final Feature file or elsewhere in this report.1Three dangers to navigation were identified in the H13093 survey area and were submitted to the Marine Chart Division's (MCD) Nautical Data Branch in one report. The Danger to Navigation Report is included in Appendix II of this report.H13093_DTON_Report2017-11-13 Features of navigational significance are discussed in the chart comparison sections above or are included in the H13093 Final Feature File submitted with this report.Data were acquired within the assigned survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report. The purpose of this survey is to provide contemporary data to update National Ocean Service (NOS) nautical charting products and to generate backscatter data which will be used in habitat mapping and substrate analysis. Much of the existing depth data dates back to 1930s vintage lead line or single beam surveys, and the areas not surveyed to modern standards are predominantly located in the shallow waters (<40 meters) where vessel traffic is highest. This poses a serious risk to life, property and the delicate ecosystem within the Channel Islands National Marine Sanctuary. H13093 multibeam and backscatter data will serve to enhance marine navigational safety, and will assist sanctuary managers, planners and researchers in the conservation of this most precious national resource.Pydro QC Tools 2 Grid QA was used to analyze H13093 multibeam echosounder (MBES) data density. The submitted H13093 variable-resolution (VR) surface met HSSD density and full coverage requirements as shown in the histograms below.The entire survey is adequate to supersede previous data.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_MB_VR_MLLW_Final.QAv5.density.pngPydro derived histogram plot showing HSSD density compliance of H13093 finalized variable-resolution MBES data.Complete multibeam echosounder (MBES) coverage was acquired to the inshore limit of hydrography, the Navigable Area Limit Line (NALL). In areas where survey coverage did not reach the 4-meter depth contour, nor the assigned sheet limits, it was due to the survey vessel reaching the inshore extent of safe navigation as shown in the figure below. These areas are characterized as being very near shore, subject to dangerous wave action or other hazards such as thick kelp.file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_NALL.jpgExamples of H13093 NALL determination.Complete Coverage (refer to HSSD Section 5.2.2.3)All waters in survey areasfile:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_Coverage.jpgH13093 MBES coverage and assigned survey limits (Chart 18729).The survey area is referred to as H13093, "Vicinity of Anacapa Island" (sheet 9). The survey was not initially included within the Project Instructions, but was subsequently added at the request of Rainier's Commanding Officer to provide a working area when adverse conditions prevailed near the assigned sheets further west; see supplemental correspondence for more information. The area encompasses approximately 26 square nautical miles around Anacapa Island and is entirely within the Channel Islands National Marine Sanctuary (CINMS).119.48869834.069586119.30477133.984052file:///M:/OPRL397RA17/Surveys/H13093/Compilation/Report/Office/SupportFiles/H13093_Assigned_Survey_Area.jpgH13093 assigned survey area (Chart 18720).26.0007502017-10-192017-10-202017-10-212017-10-312017-11-0608.7028.4325.200000000102.200000S22100048.40000028010014.147.300000280200072.00000028030014.255.2000002804Channel Islands and Vicinity, CAOPR-L397-RA-17NOAA Ship RAINIERChannel IslandsH13093Vicinity of Anacapa Island9United StatesCalifornia20000NOAA2017-08-25Benjamin K. Evans, CDR/NOAAThe 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/.metersMultibeam Echo Sounder BackscatterMultibeam Echo SounderUniversal Transverse Mercator (UTM)2017-11-062017-10-19UTCPacific Hydrographic BranchNavigable Area2017