OPR-P136-RA-19East Coast of Kodiak Island, AlaskaKodiak Island, AlaskaNOAA Ship Rainier (S221)H131052South of Cape GrevilleAlaskaUnited States400002019Benjamin K. Evans, CAPT/NOAANavigable Area2019-04-162019-05-132019-06-20Multibeam 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 referred to as H13105, "South of Cape Greville" (sheet 2) within the Project Instructions. The area encompasses approximately 57 square nautical miles of Kodiak Island's eastern coast, extending from Cape Chiniak to north of Narrow Cape. 57.6227152.1899457.386252151.906063H13105 assigned survey area (Chart 16593)SupportFiles\H13105 Assigned Survey Area.PNGData were acquired within the assigned survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report. The area of Chiniak Bay supports the second busiest and third richest fisheries port in Alaska. Chiniak Bay is the gateway to Kodiak and has a survey vintage of 1933. In 2015, the Port of Kodiak was responsible for 514 million pounds of fish and $138 million dollars of product. This area has seen many groundings and near misses due to the number of dangers to navigation and pinnacles that exist in this area. The navigation of this area is further complicated by the number of vessels trying to enter and exit the Port of Kodiak via a choke point located at the channel entrance buoy. In recent years a number of groundings in and around the area have occurred, the most famous being a 174 foot Army Landing craft that was outbound to deliver goods to a remote village in western Alaska in 2012. This survey will serve to update the nautical charts with modern data to support the above need.The entire survey is adequate to supersede previous data.Pydro QC Tools 2 Grid QA was used to analyze H13105 multibeam echosounder (MBES) data density. The submitted H13105 finalized variable-resolution (VR) surface met HSSD density and full coverage requirements as shown in the histograms below.Pydro derived plot showing HSSD density compliance of H13105 finalized variable-resolution MBES dataSupportFiles\H13105_MB_VR_MLLW_Final.QAv5.density.pngPydro derived plot showing HSSD full coverage compliance of H13105 finalized variable-resolution MBES data. SupportFiles\H13105_MB_VR_MLLW_Final.QAv5.pct_res.full_cov.pngAll waters in survey area Complete Coverage (Refer to HSSD Section 5.2.2.3)All waters in survey areaAcquire backscatter data during all multibeam data acqusition (Refer to HSSD Section 6.2)Survey coverage was in accordance with the requirements listed above and in the HSSD.H13105 MBES coverage and assigned survey limits (Chart 16593)SupportFiles\H13105 Coverage Graphic.PNGS2210361.100000002804017.900000002803033.10000034.002802022.400000002801061.600000000489.580000034.107200057.062019-05-132019-05-142019-05-152019-05-242019-05-252019-06-062019-06-072019-06-132019-06-142019-06-20Refer 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.S22170.44.728018.81.128028.81.128038.81.128048.81.1RAINIER Launches 2801, 2802, 2803, and RA-8 in Ugak Bay, AK. SupportFiles\Launches.jpgNOAA Ship RAINIER and launch 2803 in Kalsin Bay, AK. SupportFiles\Rainier.jpgAll the survey data for H13105 were acquired by survey launches 2801, 2802, 2803, 2804, and the NOAA Ship RAINIER. The launches acquired the MBES soundings, sound velocity profiles, bottom samples, and crosslines. NOAA Ship RAINIER acquired mainscheme MBES data and sound velocity profiles on survey H13105. Kongsberg MaritimeEM 710MBESKongsberg MaritimeEM 2040MBESTeledyne RESONSVP 70Sound Speed SystemAML OceanographicMVP200Conductivity, Temperature, and Depth SensorApplanixPOS MV 320 v5Positioning and Attitude SystemODIM Brooke OceanMVP200Sound Speed SystemRAINIER launch 2803 acquired 34.0 nautical miles of multibeam crosslines across all depth ranges, water masses and boat days that were safe and operationally practical. The hydrographer deems them adequate for verifying and evaluating the internal consistency of H13105 mainscheme survey data. Crossline analysis was performed using the Compare Grids function in Pydro Explorer on variable-resolution surfaces of H13105 mainscheme only and crossline only data. 99.5+% of nodes met allowable uncertainties; see Pydro generated histograms below. H13105 crossline surface analysis overlaid on mainscheme tracklines. SupportFiles\H13105 XL Coverage.PNGPydro derived plot showing node percentage-pass value of H13105 mainscheme to crossline data. SupportFiles\H13105_MS_diff_XL_4m_fracAllowErr_Freq.pngPydro derived plot showing absolute difference statistics of H13105 mainscheme to crossline data.SupportFiles\H13105_MS_diff_XL_4m_depth_delta.pngERS via ERZT00.15S221, 2801, 2802, 2803, 28043.01.00.05Total Propagated Uncertainty (TPU) values for survey H13105 were derived from a combination of fixed values for equipment and vessel characteristics, as well as from assigned values for sound speed uncertainties. The uncertainty for the Ellipsoidally Referenced Tidal Datum Model (ERTDM) used to reduce data to the ellipse was determined to be 0.15 m based on a conservative modeling of uncertainty for the separation model. Please see Appendix A Supplemental Correspondence for more details. ERTDM is a synonym to what was formerly know as poor man's Vdatum (PMVD). 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 also applied during post-processing. Finally, the post processed uncertainties associated with vessel position and attitude were applied in Caris HIPS using SBET and RMS files generated using PosPac MMS 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%). Grid QA within Pydro QC Tools 3 was used to analyze H13105 Total Vertical Uncertainty (TVU) compliance, a histogram plot of the results is shown below. Pydro derived plot showing TVU compliance of H13105 finalized multi-resolution MBES data. SupportFiles\H13105_MB_VR_MLLW_Final.QAv5.tvu_qc.pngH13105 junctions with two 2019 surveys, which are part of the same project, OPR-P136-RA-19. Comparisons were made using the Compare Grids program within Pydro. H13105 also junctions with one 2017 survey, which was part of project OPR-P136-RA-17. Following project instructions and HSSD 2019 guidance on prior year surveys, a junction comparison with H13002 was not performed.H13105 junction surveys (Chart 16593). SupportFiles\H13105 Junction Surveys.PNGH13104400002019NOAA Ship RAINIERWThe junction with 2019 survey H13104 encompasses approximately 1.91 nautical miles along the western boundary of H13105 (Figure 11). Pydro's Compare Grids results showed that 99.5+% of nodes in the common area met NOAA allowable error standards (Figure 12). Pydro derived plot showing H13104 / H13105 surface comparison statistics. SupportFiles\H13105_MB_4m_MLLW-H13104_MB_1m_MLLW_fracAllowErr_Freq.pngH13106400002019NOAA Ship RAINIERSThe junction with 2019 survey H13106 encompasses approximately 0.59 nautical miles along the southern boundary of H13105 (Figure 11). Pydro's Compare Grids results showed that 99.5+% of nodes in the common area met NOAA allowable error standards (Figure 13)Pydro derived plot showing H13105 / H13106 surface comparison statistics. SupportFiles\H13105_MB_4m_MLLW-H13106_MB_8m_MLLW_fracAllowErr_Freq.pngSonar 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.Once every four hours. Seventy 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. Two sound speed profiles were acquired for this survey outside the survey area in order to ensure all equipment and systems were operating properly. Sound speed profiles were acquired using Sea-Bird Scientific SBE 19plus Profiler and Odim Brooke Ocean MVP200. All casts were concatenated into a master file and applied using the "Nearest distance within Time" (4 hours) profile selection method. H13105 sound speed cast locations (Chart 19653).SupportFiles\H13105_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 was acquired as .all files logged during MBES operations and subsequently processed by personnel aboard RAINIER. The .GSF files created during processing and one backscatter mosaic per vessel per frequency has been delivered with this report. Backscatter processing procedures are described in the DAPR. Overview of H13105 backscatter mosaics (Chart 19653). SupportFiles\H13105_Backscatter Overview.PNGCARISHIPS/SIPS11.1QPSFledermaus Geocoder Tool Box (FMGT)7.8.1NOAA Extended Attribute file Version 5.7.H13105_MB_VR_MLLWCARIS VR Surface (CUBE)Variable Resolution19.9195.6NOAA_VRComplete MBESH13105_MB_VR_MLLW_FinalCARIS VR Surface (CUBE)Variable Resolution19.9195.6NOAA_VRComplete MBESSubmitted surfaces were generated using the NOAA recommended parameters for depth-based (Ranges) Caris variable-resolution bathymetric grids as specified in 2019 HSSD. When finalized VR surface was run through Flier Finder, no fliers were found. No soundings were designated in this survey and no Dangers to Navigation (DTONs) were detected through the survey area. Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterKodiak Island, AK9457292ERS via ERTDMP136RA2019_ERTDM_NAD83-MLLW.csarNorth American Datum 1983Projected UTM 5The Wide Area Augmentation System (WAAS) was used for real-time horizontal control during data acquisition.SBET Processing MethodPrecise Positioning-Real Time Extended (PP-RTX) processing methods were used in Applanix PosPac MMS 8.3 software to produce SBETs for post-processing horizontal correction. A comparison was made between H13105 survey data and Electronic Navigational Charts (ENC) US4AK5OM using CUBE surfaces, selected soundings, and contours created in CARIS. US4AK5OM80000082018-08-232018-08-23No shoals or potentially hazardous features exist for this survey.No charted features exist for this survey.No uncharted 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 Aids to navigation (ATONs) exist for this survey.No Maritime Boundary Points were assigned for this survey.Two bottom samples were assigned for H13105. The two assigned bottom sample locations were tested, but only the second site successfully acquired a sample. At the first bottom sample site, the bottom sampler "nibbler" closed, but failed to obtain any samples and there were no indications of bottom type when opened. At the second bottom sample site the sea floor was comprised of broken gray shells and broken black pebbles. Bottom samples are attributed in the Final Feature File. No overhead features exist for this survey.A charted (16593) cable area extends through the H13105 survey area. Evidence of cables was not identified in H13105 MBES data. 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.Benjamin K. Evans, CAPT/NOAACommanding Officer2019-09-27Hadley A. Owen, LT/NOAAField Operations Officer2019-09-27James B. JacbonsonChief Survey Technician2019-09-27Gabriella E. McGann, ENS/NOAASheet Manager2019-09-27