OPR-P136-RA-17North Coast of Kodiak Island, AKKodiak Island, AKNOAA Ship RAINIERH130027Offshore of Cape ChiniakAlaskaUnited States400002017CDR John LomnickyNavigable Area2017-03-202017-05-292017-06-12Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUniversal Transverse Mercator (UTM)Alaska (-8)Pacific 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 project area is referred to as H13002: "Offshore of Cape Chiniak" (sheet 7) within the Project Instructions. This area encompasses approximately 43 square nautical miles north northeast of Cape Chiniak, Alaska (Figure 1).57.7625152.08715657.7610205151.892347Data were acquired within survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report.The area of Chiniak Bay provides access to the second busiest and third richest fisheries port in Alaska. In 2015, the Port of Kodiak was responsible for 514 million pounds of fish and $138 million dollars of product. Chiniak Bay is the gateway to Kodiak and has a survey vintage of 1933. This survey will serve to update the nautical charts with modern data to provide more accurate navigation information for continued support of this economic hub.The entire survey is adequate to supersede previous data.Data were acquired within assigned survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report.H13002 VR density coverageSupportFiles\H13002_MB_VR_MLLW_Final_NOAA parameters.QAv5.density.pngInshore limit greater than 8 meters water depthComplete Coverage MBES (HSSD Section 5.2.2.3 Option A)Survey coverage was in accordance with the requirements listed above and in the HSSD.Acquired survey coverage with sheet limits overlaid on Charts 16594, 16593, and 16580SupportFiles\Survey coverage with sheet limits.PNG280200.120000000S2210280.460000043.700280.570000043.700000050.072017-05-292017-05-302017-06-072017-06-082017-06-092017-06-12The following table lists the mainscheme and crossline acquisition mileage for this survey: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.S22170.44.728028.51.1All data for survey H13002 was acquired by NOAA Ship Rainier and her survey launch 2802. The vessels acquired MBES depth soundings and sound velocity profiles.KongsbergEM 710MBESApplanixPOS MV v5Positioning and Attitude SystemResonSeaBat 7125 SV2MBESOdim Brooke Ocean (Rolls Royce Group)MVP200Conductivity, Temperature, and Depth SensorResonSVP71Sound Speed SystemResonSVP70Sound Speed SystemSea-Bird Electronics, Inc.19plus SEACAT ProfilerConductivity, Temperature, and Depth SensorMultibeam crosslines were acquired using Rainier S-221 across all depth ranges, water masses and boat days. H13002 crossline data is adequate for verifying and evaluating the internal consistency of survey data. A 8-meter CUBE surface was created using only H13002 mainscheme lines, and a second 8-meter surface was created using only crosslines. A difference surface was then generated in Caris from which statistics were derived. For its respective depths, the difference surface was compared to IHO allowable Total Vertical Uncertainty (TVU) standards. In total, 100% of the depth differences between H13002 mainscheme and crossline data met HSSD TVU standards. The analysis was performed on H13002 MBES data reduced to Mean Lower-Low Water (MLLW) using Ellipsoidally Referenced Zoned Tides (ERZT) methodsH13002 Crosslines overlaid on charts 16593, 16594, and 16580SupportFiles\Crosslines with outline and tracklines.PNGCrossline IHO-compliance statisticsSupportFiles\XL_increased accuracy.PNG00.129ERS via ERZT28023N/A0.15S-221N/A10.05Total Propagated Uncertainty (TPU) values for survey H13002 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 accounted for by examining the field generated one thousand-meter resolution separation model and statistically determining a measured value. A measured uncertainty of 0.129 meters was entered to account for ERZT processing methods. See the 2017 DAPR for further information. 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 Reson MBES sonars were recorded and applied during post-processing. Applanix TrueHeave (POS) files, which record estimates of heave uncertainty, were also applied during post-processing. Finally, the post-processed uncertainties associated with vessel roll, pitch, yaw and position were applied in CARIS HIPS using SBET /RMS files generated using POSPac software. Uncertainty values of the submitted finalized grid were calculated in CARIS using "Greater of the Two" of uncertainty and standard deviation (scaled to 95%). Pydro QC tools 2 were used to analyze H13002 TVU compliance; a histogram plot of the results is shown below (Figure 5).Pydro derived histogram plot showing TVU compliance of H13002 finalized multi-resolution MBES dataSupportFiles\H13002_MB_VR_MLLW_Final_NOAA parameters.QAv5.tvu_qc.pngH13001400002017NOAA Ship RAINIERWOne junction comparison exists for H13002 (H13001), which was acquired concurrently with this survey. See Description Report for H13001 for junction analysis.Sonar 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.None ExistThere were no other factors that affected corrections to soundings.Sound Speed Cast Frequency: 38 sound speed profiles were acquired for this survey at discrete locations within the survey area at least once every four hours, when significant changes in surface sound speed were observed, or when operating in a new area. Sound speed profiles were acquired using Sea-Bird 19plus SEACAT Profiler and Odim Brooke Ocean MVP200. All casts were concatenated into a master file and applied to MBES data using the "Nearest distance within time" (4 hours) profile selection method.”Locations of sound speed casts taken during acquisition on H13002SupportFiles\SVP casts.PNGAll equipment and survey methods were used as 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.Raw backscatter data were logged as .ALL files for delivery to NOAA's Pacific Hydrographic Branch. No post-processing or QC tasks were performed by the field unit.CARISHips and Sips9.1, 10.2, 10.3NOAA Extended Attribute Files V5.5H13002_MB_VR_MLLWCUBE99935.0220.7VRComplete MBESH13002_MB_VR_MLLW_FinalCUBE99935.0220.7VRComplete MBESSubmitted surfaces were generated using the recommended parameters for depth-based Caris variable resolution bathymetric grids with Calder-Rice Density as specified in HSTD 2017-2. The resolution values indicated in Table 10 above are not accurate: the XML-DR schema used to generate this report does not accommodate variable resolution grids; the 999 value is obviously spurious and was entered merely as a "place holder." The XML-DR team is aware of this issue and are working to update the schema.Calder Rice Density was used not Depth Based Variable Resolution.Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterWomens Bay9457292TCARI9457292.tidFinal ApprovedP136RA2017.tcFinal2017-06-232017-07-06See attached Tide Note dated July 6, 2017.ERS via ERZTH13002_NAD83_MLLW_SEP_1000m.csarEllipsoidally Referenced Zone Tides (ERZT) methods were used to transform between the ellipsoid and the water level data. A 1000-meter resolution separation model was computed between the ellipsoid and MLLW using real-time position measurements observed during the survey relative to the vessel water line and the TCARI tide file. "GPS tides" were then computed using the above separation model and the corrected GPS-height-to-water-level data (SBET). The 1000-meter resolution model was generated in NAD83 as were the SBETs.North American Datum of 1983 (NAD83)Universal Transverse Mercator (UTM) Zone 5 NorthSingle Base9715WoodyThe Wide Area Augmentation System (WAAS) was used as real-time horizontal control for this survey. Chart comparisons were performed using a Caris sounding layer based on the 8m surface from H13002 and a contour layer also based on the 8m surface. The survey-derived contours and soundings were overlaid on ENC chart US4AK5OM and compared for general agreement and to identify areas of significant change. Aside from slight changes in the 50-fathom contour, no significant changes were noted. US4AK5OM chart comparison with 50 fathom contour highlighted.SupportFiles\ENC chart comparison.PNGUS4AK5OM80000222017-01-192017-02-21falseIn the area of survey H13002, Raster chart 16593 coincides with Electronic Navigation Chart (ENC) US4AK5OM, therefore a comparison between H13002 and the Raster chart is equivalent to the following comparison with ENC US4AK5OM. Several areas in H13002 were found to be different from charted depths, but not drastically so. Close examination of H13002 overlaid on ENC US4AK5OM revealed clusters of uncharted soundings less than 50 fathoms as well as a shift in the 50-fathom contour in the southwest corner of the survey (Figure 7).No Maritime Boundary Points were assigned for this survey.No charted features exist for this survey.No new navigationally significant features were detected during this survey.No Danger to Navigation Reports were submitted for this survey.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.Field survey teams were unsuccessful in acquiring a bottom sample using the approved sampling methods after multiple attempts.Shoreline was not assigned in the Hydrographic Survey Project Instructions or Statement of Work.No prior survey comparisons were provided for this survey.No ATONs were specifically assigned for this survey and none exist within the assigned sheet limits.No overhead features were observed within the H13002 survey area.A charted (16593) cable area extends through the H13002 survey area; no evidence of cables was identified in H13002 MBES data.No ferry routes or terminals exist for this survey.There are no platforms within the H13002 survey area.Unexploded ordnance (reported 2013) is charted (16593) within the survey area. No evidence of these features was discovered, nor was this survey designed to observe such evidence.No present or planned construction or dredging are known to 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 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.John J. Lomnicky, CDR/NOAACommanding Officer, NOAA Ship Rainier2017-10-11Scott Broo, LT/NOAAField Operations Officer, NOAA Ship Rainier2017-10-11James B. JacobsonChief Survey Technician, NOAA Ship Rainier2017-10-11Bethany McAcy, ENS/NOAASheet Manager, NOAA Ship Rainier2017-10-11