OPR-P136-RA-17North Coast of Kodiak Island, AKKodiak Island, AKNOAA Ship RAINIERH129972FinalLong IslandAlaskaUnited States400002017John J. Lomnicky, CDR/NOAANavigable Area2017-03-092017-04-202017-05-13Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUniversal Transverse Mercator (UTM)UTCPacific Hydrographic BranchNOAAThe survey area is referred to as "Long Island" (sheet 2) within the Project Instructions. The area encompasses approximately 7 square nautical miles between Woody Island and Long Island. Data within the assigned survey were required to meet NOAA Object Detection requirements.57.8170138889152.361457.7396972222152.226169444H12997 survey area as assigned in Project Instructions (Chart 16594)SupportFiles\H12997_Survey Limits.pngData were acquired within survey limits in accordance with the requirements in the Project Instructions and the HSSD unless otherwise noted in this report.The 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.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. Pydro QC Tools 2 Grid QA was used to analyze H12997 object detection multibeam echosounder (MBES) data density. The submitted H12997 variable-resolution (VR) surface met HSSD density requirements.Pydro derived histogram plot showing HSSD object detection compliance of H12997 object detection MBES data within the VR CUBE surface. SupportFiles\H12997_MB_VR_MLLW_Final.QAv5.density.pngAll depths within H12997Object Detection Coverage (HSSD Section 5.2.2.2)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 vessel reaching the inshore extent of safe navigation as shown in the figure below. These areas were generally located very near shore, and were subject to dangerous wave action and other hazards. Coverage did not extend to the 4 meter contour in areas that were deemed unsafe by launch personnel, which include some shoreline and rocky features (Figure 3 and 4). One small "holiday" in survey coverage exists over Vasilief Rock, which measures approximately 1.5X0.5 meters (Figure 5). Approximately 10 small "holidays" in survey coverage exist due to acoustic shadowing on the down slopes of rocky features (Figure 6). These gaps in coverage were examined to ensure that least depths were obtained over navigationally significant features. An additional 605 holidays were discovered in Object Detection surfaces after the field unit had left the survey area. Some of these holidays occur in the deepest part of the 0.5 meter and 1 meter surfaces, but the vast majority of them are in extreme nearshore areas (Figure 7). These holidays were caused by the effects of the sea state on vessel motion (yaw and pitch). Therefore these holidays are generally only 1 node long (along track), but 3+ nodes in the across track (Figure 8). These holidays were likely missed during acquisition due to incorrect CUBE parameters being used for BASE surface creation in CARIS HIPS. When default CUBE parameters are chosen, the search radius and capture distances will be higher than if the NOAA Object Detection Parameter is used. While these holiday areas do not meet Object Detection standards, they represent a small percentage of the overall survey area. Close inspection of the affected areas was conducted in CARIS HIPS Subset Editor with special attention paid to the seafloor for potential shoaling trends. The hydrographer recommends that this survey be processed and compiled to Object Detection standards. Northern shore of the peninsula on Long Island was not completely covered due to rocky features. The yellow surface indicates the 4 meter contour at MLLW where the NALL was met.SupportFiles\H12997_Survey Coverage Gap_ N Long Is_.pngComplete coverage was not achieved near rocky features due to safety concerns. The yellow surface indicates the 4 meter contour at MLLW where the NALL was met. SupportFiles\H12997_Survey Coverage Gap_ N Woody Is.pngSubset and chart view of gap in survey coverage over Vasilief rock, note the least depth of rock was obtained.SupportFiles\H12997_Holiday_Vasilief Rock.pngChart view of acoustic shadowing due to rocky features.SupportFiles\H12997_Holiday_Acoustic Shadows 2.pngBlue tick marks indicate ares of holidays, mostly occurring near the shoreline.SupportFiles\H12997_ObjectDetectionHolidaysOverview.pngExample of holidays found offshore.SupportFiles\H12997_ObjectDetectionHolidaysCloseup.pngH12997 Achieved Survey Coverage (Chart 16594)SupportFiles\H12997_Survey Coverage_Closeup.pngH12997 Geographic Context (Chart 16594)SupportFiles\H12997_Survey Coverage_Overview.png28020149.04000000028040135.570000011.3200284.610000011.3203.833011607.152017-05-132017-05-112017-05-042017-04-282017-04-272017-04-262017-04-252017-04-242017-04-20Refer 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.28028.81.128048.81.119055.70.3All data for H12997 were acquired using survey launches 2802 and 2804 and skiff 1905. The survey launches acquired MBES depth soundings, backscatter data, and sound speed profiles. The skiff conducted shoreline verification. ApplanixPOS-MV V5Positioning and Attitude SystemResonSeaBat 7125 SV2MBESResonSVP71Sound Speed SystemSea-Bird ElectronicsSBE 19Plus SEACAT ProfilerConductivity, Temperature, and Depth SensorVelodyneVLP-16Lidar SystemMultibeam crosslines were acquired by using a Reson 7125 SV2 on launches 2802 (RA-5) and 2804 (RA-6) across most but not all depth ranges, water masses, and boat days. H12997 crossline data is adequate for verifying and evaluating the internal consistency of survey data. A 1-meter CUBE surface was created using only H12997 mainscheme lines, with a second 1-meter CUBE surface was created using only crosslines (Figure 11). A difference surface was created 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, 99.4% of the depth differences between H12997 mainscheme and crossline data meet HSSD TVU standards (Figure 12). The analysis was performed on H12997 MBES data reduced to Mean Lower-Low Water (MLLW) using Ellipsoidally Referenced Zoned Tides (ERZT) methods. H12997 CrosslinesSupportFiles\H12997_Crosslines.pngPercentage of difference surface nodes between H12997 mainscheme and crosslines ERZT data that met HSSD allowable TVU standards.SupportFiles\H12997_Crosslines_table.png00.018ERS via ERZT2802, 28043.00.15 Total Propagated Uncertainty (TPU) values for H12997 were derived from a combination of fixed values for equipment and vessel characteristics, as well as field assigned values for sound speed uncertainties. Tidal uncertainties were accounted for by examining the created 1000-m separation model and statistically determining a measured uncertainty. The measured tide uncertainty value of 0.018 meters was entered to account for ERZT processing methods. 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 multibeam sonars were recorded and applied during post processing. Applanix TrueHeave (POS) files, which record estimates of heave uncertainty, were also applied during post processing. The post processed uncertainties associated with vessel roll , pitch, yaw and navigation, were applied in CARIS HIPS and SIPS using SBET/RMS files generated using POSPac software. Uncertainty values of submitted finalized grids were calculated in CARIS HIPS and SIPS using the "Greater of the Two" of uncertainty and standard deviation (scaled to 95%). Pydro QC tools 2 were used to analyze H12997 TVU compliance; a histogram plot of the results is shown below (Figure 13).VR surface meets HSSD uncertainty standards.SupportFiles\H12997_MB_VR_MLLW_Final.QAv5.tvu_qc.pngThree surveys junction with H12997 (see Table 8). Two junction analyses, for H12996 and H10913, were conducted for this Descriptive Report. See the Descriptive Report for H13003 for that junction analysis. Surveys H12996 and H13003 were acquired concurrent to H12997.H12997 Junction Surveys.SupportFiles\Junction Survey Overview.pngH13003400002017NOAA Ship RAINIERESee H13003 DR for junction analysis.H12996400002017NOAA Ship RAINIERNOverlap with survey H12996 was approximately 5,800 meters wide along the northern boundary of H12997 (Figure 15). Depths in the junction range from 19 to 77 meters. For the respective depths, the difference surface was compared to the allowable TVU standards specified in the HSSD. In total, 99.4% of the depth difference between H12997 and junction survey H12996 are within allowable uncertainties. H12997 junction with H12996.SupportFiles\H12997_H12996_Junction Chart.pngSummary table indicating the percentage of nodes from the junction overlap that met HSSD allowable TVU standards. SupportFiles\H12997_H12996_JunctionTable.pngH10913100001999NOAA Ship RAINIERSOverlap with survey H10913 was approximately 3,500 meters wide along the southern boundary of H12997 (Figure 17). Depths in the junction range from 18 to 71 meters. For the respective depths, the difference surface was compared to the allowable TVU standards specified in the HSSD. In total, 97.9% of the depth difference between H12997 and junction survey H10913 are within allowable uncertainties. H12997 junction with H10913.SupportFiles\H12997_H10913_Junction chart.pngSummary table indicating the percentage of nodes from the junction overlap that met HSSD allowable TVU standards. SupportFiles\H12997_H10913_Junction Table.png One additional junction comparison was conducted during office processing. Survey F00646 junctions with H12997 to the west and was acquired in 2014 by the Rainier with an approximate overlap 1,830 meters long and 150 meters wide. The agreement between the overlapping areas of the 4-meter combined surface from F00646 and the 4-meter surface from H12997 were compared using the Compare Grids tool in Pydro XL. The statistical output indicates that 95% of surface nodes are within the allowable uncertainty limits. H12997 junction with F00646.file:///M:/OPRP136RA17/Surveys/H12997/Compilation/Report/Components/SupportFiles/Junction_F00646_overview.pngResults from surface comparison indicating that 95% of the difference surface nodes are within allowable TVU limitsfile:///M:/OPRP136RA17/Surveys/H12997/Compilation/Report/Components/SupportFiles/Junction_F00646_MB_4m_MLLW_Combined_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.Sound speed profiles were acquired using the SBE 19plus CTD probes at discrete locations within the survey area at least once every four hours, when significant changes in surface speed were observed, or when surveying a new area (Figure 19). 39 CTD casts were acquired and applied to H12997 MBES data using the nearest distance within time (4 hours) method.Location of CTD casts for H12997SupportFiles\H12997_Cast Location.pngAll equipment and survey methods were used as detailed in the DAPR.False Positive FliersPydro QC Tools 2 identified 22 potential fliers in the submitted H12997 finalized surface; all were determined to be false positives.All data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Raw Backscatter was logged as a 7k file and has been sent to the Processing Branch. Backscatter was not processed by the field unit.CarisHIPS/SIPS9.1, 10.2NOAA Extended Attribute Files V_5_5.H12997_MB_VR_MLLWCUBE999-0.7180.56VRObject DetectionH12997_MB_VR_MLLW_FinalCUBE999-0.7180.56VRObject DetectionSubmitted object detection surfaces were generated using the recommended parameters for density-based Caris variable resolution, bathymetric grids as specified in HSTD 2017-2. The resolution values indicated in the table 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 9 H12997 soundings were designated: 8 as DTONs, and 1 non-DTON feature for inclusion in the H12997_Final_Feature_File.The submitted surfaces and the surfaces generated during office processing were created using the ranges-based parameters for VR surfaces, not the density-based parameters as stated above. Four additional soundings were designated during review: 1 as a DTON and 3 on rocks. These were included in the Final Feature File for a total of 13 designated soundings.Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterKodiak Island, Womens Bay9457292TCARIH12997_TCARI_Features.tidFinal ApprovedP136RA2017.tcFinal2017-06-022017-06-16H12997 features were tide corrected using a .tid file created in Pydro using the "TCARI TID file via S-57" function then loaded in CARIS Notebook. H12997 MBES data were reduced to MLLW using ERZT processing methods. ERS via ERZTH12997_NAD83_MLLW_SEP_1000m.csarEllipsoidally Referenced Zone 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 DAPR for additional information. North American Datum of 1983 (NAD83)Universal Transverse Mercator (UTM) Zone 5 NorthSmart BaseSingle Base9715WoodyChart comparisons were made using a CARIS sounding and contour layer derived from a variable resolution CUBE surface. The contours and soundings were overlaid on the charts and compared for general agreement and to identify areas of significant change. 165802546350000152015-032017-02-072017-02-18H12997 data in general was with agreement with chart 16580. However, as seen in Figure 20, charted contours can be off by hundreds of meters. The 10-fathom contour marking the shoal area that extends between Woody Island and Long Island aligns poorly.SupportFiles\16580_10ftm_contour_middle channel.png16594255380000142015-012015-01-012015-01-01In general, H12997 data was in agreement with charted contours on 16594. Charted contours had the greatest separation roughly 100 meters between the charted 10-fathom contour and H12997 10-fathom contour on the east side of the channel (Figure 21). The charted contours around Vasilief Rock were more shallow than H12997 contours (Figure 22). Variation between charted contours and H12997 contours. SupportFiles\16594_Eastern shore.png10-fathom contour around Vasilief Rock is smaller than what is charted. SupportFiles\16594_Vasilief Rock_contour.pngOne additional larger scale chart covers the western and southern half of the survey. Chart 16595 (Scale 1:20,000, Ed. 1, Ed. Date 11/2012, LNM 9/1/2018, NM 9/1/2018) coincides with ENC US5AK5EM and was compared with survey data during office review. The comparison is discussed in the ENC section below.US4AK5PM8000092016-08-242016-08-24falseA comparison was made between H12997 derived contours and ENC US4AK5PM with the following results: In general, charted contours were generally in agreement with the ENC contours except for the shoal area North of Woody Island (Figure 23) and the western side of Long Island (Figure 24). The 3, 5, and 10-fathom contours derived from H12997 are shoaler than charted contours.SupportFiles\US4AK5PM_N Woody Is.pngThe 3, 5, and 10-fathom contours derived from H12997 are shoaler than charted contours.SupportFiles\US4AK5PM_Between Woody and Long.png A larger scale ENC (US5AK5EM) overlaps the southern and western portions of the survey so a chart comparison with this ENC was conducted during office processing. The contours and soundings from US5AK5EM (Scale 1:20000, Edition 15, Application Date 12/4/2017, Issue Date 3/8/2018) were compared to those derived from H12997. Soundings were generally within 1 to 2 fathoms and contours closely followed charted contours with a few exceptions where the contours differed by ~100 meters.Overview of ENC US5AK5EM and ENC US4AK5PM.file:///M:/OPRP136RA17/Surveys/H12997/Compilation/Report/Components/SupportFiles/ChartComp_Overview.pngApproximate ~100-meter difference between charted and survey contours.file:///M:/OPRP136RA17/Surveys/H12997/Compilation/Report/Components/SupportFiles/ChartComp_contours1.pngApproximate ~100-meter difference between charted and survey contours.file:///M:/OPRP136RA17/Surveys/H12997/Compilation/Report/Components/SupportFiles/ChartComp_contours2.pngNo Maritime Boundary Points were assigned for this survey.No charted features exist for this survey.No uncharted features exist for this survey.8Danger to Navigation Reports are included in Appendix II of this report. Features of navigational significance are discussed in the chart comparison sections above or are included in the H12997 Final Feature File submitted with this report.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.Three bottom samples were investigated for this survey; the results are included in the H12997 Final Feature File submitted with this Report.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 H12997_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 prior survey comparisons exist for this survey.No Aids to navigation (ATONs) exist for this survey.No overhead features exist for this survey.A charted (16594, 16595) cable area extends through the H12997 survey area from Woody Island to Long Island; no evidence cables was identified in H12997 MBES data.No ferry routes or terminals exist for this survey.No platforms exist for this survey.One wreck was found within the survey area; its position and other information is included in the H12997 Final Feature File submitted with this report. There are no other significant features in the H12997 survey area that were not discussed elsewhere in this report.H12997 wreck.SupportFiles\H12997_Wreck.jpgNo 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 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 Rainier2018-03-06Scott E. Broo, LT/NOAAField Operations Officer, NOAA Ship Rainier2018-03-06James B. JacobsonChief Survey Technician, NOAA Ship Rainier2018-03-06Jennifer S. Kraus, ENS/NOAASheet Manager2018-03-06