H12999 MBES data identified a least depth of 16-fathoms over a shoal reported in 2006. SupportFiles\Shoal_rep_2006.jpgH12999 MBES data overlaid on Chart 16593 showing least depth on shoal reported in 2006.Six bottom samples were investigated for this survey; the results are included in the H12999 Final Feature File submitted with this report.No Maritime Boundary Points were assigned for this survey.H12999 survey data coincide with sections of ENC US4AK5OM and US4AK5PM. A positional offset between the two ENCs of approximately 20-70 meters was identified at the junction of these charts at the north end of the H12999 survey area (Figure 16). A comparison was made between H12999 derived contours and ENC US4AK5OM with the following results: Except as noted below, H12999 3-fathom and 10-fathom contours were generally inshore of the ENC positions; the H12999 50-fathom contour showed good general agreement with the ENC (Figure 17). In the Svitlak Island area, H12999 data identified many inconsistencies with the chart including a 3-meter shoal, located on the charted 5-fathom ENC contour, approximately 1600 meters west of Utesistoi Island. The area southwest of Svitlak Island is a complex mix of shoals, foul ground and ledges; the ENC requires significant revision in that region (Figure 18). Eleven Dangers to Navigation (DTON) were identified in the H12999 survey area and submitted to Marine Chart Division's (MCD) Nautical Data Branch. Refer to the H12999_DTON_Report for location and description of these dangers. SupportFiles\ENC_Discontinuity_with_Inset.jpgENC Discontinuity. Red circles identify areas with positional offsets between ENCs of approximately 20 to 70 meters within the H12999 survey area.SupportFiles\H12999_Contour_ENC_Comparison_Lables.jpgENC US4AK5OM overlaid with H12999 derived contours.SupportFiles\Svitlak_Area_3_fathom_Contours_Labled.jpgH12999 3-fathom contours (in red) overlaid on ENC US4AK5OM showing numerous discrepancies between survey data and the chart.2015-10-054US4AK5OM800002015-10-05falseENC US4AK5PM covers the northern-most nautical mile of H12999 data. The survey derived 3-fathom and 10-fathom contours were found to be inshore of the ENC charted positions; the H12999 50-fathom contour showed good general agreement with the ENC. Overall, H12999 soundings were deeper than charted depths.2017-07-3011US4AK5PM800002017-04-28falseEleven dangers to navigation were identified in the survey area and submitted in one report. The H12999 Danger to Navigation Report is included in Appendix II of this Descriptive Report.1H12999_DTON_Report2017-08-05One additional DTON was identified and submitted for charting during office review. Features of navigational significance are discussed in the chart comparison sections above or are included in the H12999 Final Feature File submitted with this report. No new navigationally significant features were detected that were not included in the H12999 Final Feature File or elsewhere in this report.A comparison was made between H12999 survey data and Electronic Navigation Charts (ENC) US4AK5OM and US4AK5PM using CUBE surfaces, selected soundings and contours created in Caris.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.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 H12999_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. No new surveys or further investigations are recommended for this area.No overhead features were observed within the H12999 survey area.A charted (16593) cable area extends through the H12999 survey area from Broad Point to Isthmus Point; no evidence of cables were identified in H12999 MBES data.No present or planned construction or dredging are known to exist within the survey limits.There are no platforms within the H12999 survey area.No ferry routes or terminals exist for this survey.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. The "NOAA-UAF" FL Y 4s Private buoy charted at the northeast corner of the H12999 survey area was not observed in the field. The charted Marker at the head of Kalsin Bay was not seen.There are no significant features in the H12999 survey area that were not discussed elsewhere in this report.No new insets are recommended for this area.SupportFiles\H12999_Coverage.jpgH12999 MBES coverage and assigned survey limits (Chart 16593).2017-05-122017-05-132017-05-142017-05-152017-05-162017-05-252017-05-262017-05-282017-05-292017-05-302017-05-312017-06-012017-06-102017-06-112017-06-132017-06-202017-06-222017-06-232017-06-262017-06-272017-06-3024.34.000000060500000000143.5028010000000152.00280220.300000052.5028033.9000000256.802804016.506155Data were acquired within assigned survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report. Pydro QC Tools 2 Grid QA was used to analyze H12999 multibeam echosounder (MBES) data density. The submitted H12999 variable-resolution (VR) surface met HSSD density requirements.The entire survey is adequate to supersede previous data.SupportFiles\H12999_MB_VR_MLLW_Final.QAv5.density.pngPydro derived histogram plot showing HSSD density compliance of H12999 finalized variable-resolution MBES data.All waters in survey area except for H12997 and designated S-57 cvrage areasComplete Coverage (refer to HSSD Section 5.2.2.3). Note All MBES acquisition requires backscatter acquistion (refer to HSSD Section 6.2)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 vessle reaching the inshore extent of safe navigation as shown in the figure below. These areas were generally located very near shore, were subject to dangerous wave action and other hazards.SupportFiles\H12999_NALL.jpgExamples of H12999 NALL determination.The survey area is referred to as "Kalsin Bay" (sheet 4) within the Project Instructions. The area encompasses approximately 17 square nautical miles extending from Broad Point to Isthmus Point and southwest to the head of Kalsin Bay.SupportFiles\H12999_Survey_Area_Overview_and_Inset.jpgH12999 assigned survey area.57.588126152.29679757.707464152.474055The area of Chiniak Bay supports the second busiest and third richest fisheries port in Alaska. In 2015, the Port of Kodiak was responsible for 515 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 area has seen many groundings and near misses due to the number of dangers to navigation and submerged 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 long Army landing craft that was outbound to deliver goods to a remote village in western AK in 2012. This survey will serve to update the nautical charts with modern data to support safe navigation.Data were acquired within survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report.OPR-P136-RA-17NOAA Ship RAINIERKodiak Island, AKNorth Coast of Kodiak IslandNOAAUniversal Transverse Mercator (UTM)Multibeam Echo Sounder BackscatterMultibeam Echo SounderThe 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/.meters2017-03-09Navigable Area2017-06-302017-05-12John J. Lomnicky, CDR/NOAA2017UTCAtlantic Hydrographic BranchH1299940000United StatesPossible reserve sheet for remote launch party4AlaskaKalsin BayRefer 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.Positioning and Attitude SystemPOS M/V v5ApplanixMBESSeaBat 7125 SV2ResonMBESSeaBat 7125-BResonSound Speed SystemSVP71ResonConductivity, Temperature, and Depth SensorSBE 19plus SEACAT ProfilerSea-Bird Electronics8.81.128018.81.128028.81.128038.81.128045.70.3519055.70.351907SupportFiles\S221_Rainier.jpgNOAA Ship Rainier near Kalsin Bay with survey launches 2803 and 2802 in view.All sounding systems were calibrated as detailed in the DAPR.All data reduction procedures conform to those detailed in the DAPR.NOAA Extended Attribute Files V_5_5.Submitted surfaces were generated using the recommended parameters for depth-based Caris variable resolution bathymetric grids as specified in HSTD 2017-2. The resolution values indicated in Table 9 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. A total of thirteen H12999 soundings were designated: eleven as DTONs, and two non-DTON features for inclusion in the H12999_Final_Feature_File.H12999_MB_VR_MLLW144.480.12CUBEComplete MBES999VRH12999_MB_VR_MLLW_Final147.480.12CUBEComplete MBES999VRIn some nearshore areas, marine vegetation inhibited accurate bottom detection. In cases where it was possible to discern the true bottom from marine vegetation, the obscuring soundings were rejected. However, when unable to clearly distinguish between the apparent seafloor and vegetation, no soundings were rejected.Mid-Water Column Acoustic ScatterSupportFiles\H12999_Marine_Vegetation_Area.jpgExample of area where marine vegetation may impede accurate seafloor detection.All equipment and survey methods were used as detailed in the DAPR.There were no conditions or deficiencies that affected equipment operational effectiveness.None ExistMultibeam crosslines were acquired using Rainier launches 2803 and 2804 across all depth ranges, water masses and boat days that were practical; they are adequate for verifying and evaluating the internal consistency of survey data. A 4-meter CUBE surface was created using only H12999 mainscheme lines, and a second 4-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, 99.98% of the depth differences between H12999 mainscheme and crossline data met HSSD TVU standards. The analysis was performed on H12999 MBES data reduced to Mean Lower-Low Water (MLLW) using Ellipsoidally Referenced Zoned Tides (ERZT) methods.SupportFiles\H12999_Crossline_IHO_Compliance_Stats.jpgSummary table indicating percentage of difference surface nodes between H12999 mainscheme and crossline data that met HSSD allowable TVU standards.SupportFiles\H12999_XLs.jpgH12999 crossline surface overlaid on mainscheme tracklines showing good temporal and geographic distribution.Sonar system quality control checks were conducted as detailed in the quality control section of the DAPR.00.0224ERS via ERZT3N/A2801, 2802, 2803, 28040.15Total Propagated Uncertainty (TPU) values for survey H12999 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 0.0224 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 submitted finalized grids 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 H12999 TVU compliance; a histogram plot of the results is shown below.SupportFiles\H12999_MB_VR_MLLW_Final.QAv5.tvu_qc.pngPydro derived histogram plot showing TVU compliance of H12999 finalized multi-resolution MBES data.SupportFiles\H12999_SVP.jpgH12999 sound speed cast locations.Seventy four 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 Profilers. All casts were concatenated into a master file and applied to MBES data using the "Nearest distance within time" (4 hours) profile selection method.40000NOAA Ship RAINIER2017NWH12998The junction with survey H12998 encompassed 0.29 square nautical miles along the northwestern boundary of H12999. A comparison was made using a difference surface derived from the 4-meter CUBE surfaces of each survey. Analysis of the difference surface indicated that H12999 is an average of 0.10 meters deeper than H12998 with a standard deviation of 0.21 meters. For the respective depths, the difference surface was compared to the allowable TVU standards specified in the HSSD. In total, 99.85% of the depth differences between H12999 and junction survey H12998 were within allowable uncertainties.SupportFiles\H12999_Junction_H12998_4m_labels.jpgH12999 junction survey H12998 showing HSSD TVU compliance.SupportFiles\H12999_Diff_H12998_4m_Stats.jpgSummary table indicating percentage of nodes that met HSSD allowable TVU standards for the H12999 / H12998 junction.40000NOAA Ship RAINIER2017EH13000The junction with survey H13000 encompassed 0.44 square nautical miles along the eastern boundary of H12999. A comparison was made using a difference surface derived from the 4-meter CUBE surfaces of each survey. Analysis of the difference surface indicated that H12999 was an average of 0.08 meters deeper than H13000 with a standard deviation of 0.21 meters. For the respective depths, the difference surface was compared to the allowable TVU standards specified in the HSSD. In total, 99.83% of the depth differences between H12999 and junction survey H13000 were within allowable uncertainties.SupportFiles\H12999_Diff_H13000_labels.jpgH12999 junction survey H13000 showing HSSD TVU compliance.SupportFiles\H12999_Diff_H13000_Stats.jpgSummary table indicating percentage of nodes that met HSSD allowable TVU standards for the H12999 / H13000 junction.10000NOAA Ship RAINIER1999NH10913The junction with survey H10913 encompassed approximately 0.08 square nautical miles along the northern boundary of H12999. An 8-meter surface of H10913 data was created with Caris Base Editor using the following steps: a point cloud was generated from the H10913.a93 file provided by NOAA's Operations Branch, a Triangulated Irregular Network (TIN) model was created, long edges removed, then used to interpolate the surface. An 8-meter CUBE surface of H12999 data was created in Caris HIPS, then a difference surface was derived between the two. Analysis of the 8-meter difference surface indicated that H12999 is an average of 0.07 meters shoaler than H10913 with a standard deviation of 1.37 meters. H10910 is a 1999 vintage survey, acquired during a time when robust uncertainty calculation and documentation was not standard practice, therefore it was not possible to conduct detailed IHO TVU compliance analysis for this junction. The relatively high standard deviation of the junction data and the larger depth differences seen, are attributed to the comparatively low resolution of the H10913 data set, high seafloor relief in some areas and the lower quality of the surface along some of its edges.SupportFiles\H12999_Diff_H10913_Junction_8m.jpgH12999 / H10913 junction.Three surveys junction with H12999, two are contemporary and part of project OPR-P136-RA-17, the third was conducted by NOAA Ship Rainier in 1999.SupportFiles\H12999_Junction_Surveys.jpgH12999 junction surveys.Raw Backscatter data were logged as .7k files for delivery to NOAA's Pacific Hydrographic Branch. Although not required at the time this survey was conducted, backscatter data were processed by the field unit and mosaics generated. One 2-meter resolution mosaic was created for each vessel / frequency, as well as a combined 6-meter resolution mosaic of the entire H12999 survey area.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.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.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.2017-10-02Commanding Officer, NOAA Ship RainierJohn J. Lomnicky, CDR/NOAA2017-10-02Field Operations Officer, NOAA Ship RainierSteven Loy, LT/NOAA2017-10-02Chief Survey Technician, NOAA Ship RainierJames B. Jacobson2017-10-02Senior Survey Technician, NOAA Ship RainierB.D. Jackson9457292Kodiak Island, Womens BayTCARIH12999 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. H12999 MBES data were reduced to MLLW using ERZT processing methods. P136RA2017.tcFinalH12999_TCARI_Features.tidFinal Approved2017-07-182017-07-02H12999_NAD83_MLLW_SEP_1000m.csarEllipsoidally Referenced Zoned Tides (ERZT) methods were used to transform between the ellipsoid and 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 separation model was generated in NAD83 as were the SBETs. Refer to the Rainier 2017 DAPR for additional imformation.ERS via ERZTMean Lower Low WaterAdditional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Woody9715The Wide Area Augmentation System (WAAS) was used for real-time horizontal control for this survey.Single BaseNorth American Datum of 1983 (NAD83)Universal Transverse Mercator (UTM) Zone 5 North