OPR-Q191-KR-13Krenitzin Islands, AlaskaKrenitzin IslandsFugro Pelagos, Inc.H125486The Hydrographic Sheet should be accompanied by this form, filled in as completely as possible, when the sheet is forwarded to the Office.Reef Point to North HeadAlaskaUnited States400002013Dean MoylesNavigable Area2013-05-152013-06-282013-07-20Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUTMUTCPacific 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. Revisions and notes in red were generated during office processing. The processing branch concurs with all information and recommendations in the DR unless otherwise noted. Page numbering may be interrupted or non-sequential. All pertinent records for this survey, including the Descriptive Report, are archived at the National Geophysical Data Center (NGDC) and can be retrieved via http://www.ngdc.noaa.gov/. ContractorH12548 is located in the area from Reef Point to North Head.54.27556165.8891754.08139166.21611Survey Limits were acquired in accordance with the requirements in the Project Instructions and the HSSD.The purpose of this work is to provide NOAA with modern and accurate hydrographic survey data for the area from Reef Point to North Head. The survey covered 22.24 square nautical miles of critical survey area as designated in the NOAA Hydrographic Survey Priorities, 2012 edition. The entire survey is adequate to supersede previous data.Survey Coverage was in accordance with the requirements in the Project Instructions and the HSSD.H12548 Survey Limitsfile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/H12548%20Survey%20Limits.pngOcean Pioneer0208.8000008.980R2035.960000000D20312.30000017.0500557.060000026.0304.675000022.242013-06-282013-06-292013-06-302013-07-012013-07-062013-07-112013-07-122013-07-142013-07-152013-07-172013-07-182013-07-192013-07-20There were 3 bottom samples and 40 DPs collected for the 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.Ocean Pioneer20514R2293D2293Due to an inoperable davit, production for vessel R2 was limited for the OPR-Q191-KLR-13 survey. The last day of survey for vessel R2 was JD 181.JD 181 2013 equates to June 30, 2013.WaterLOG H3611 (Radar Water Level Sensors) were installed on the port and starboard gunwales of M/V Ocean Pioneer to obtain a more precise static draft measurement. Samples were taken over a 10 minute period and averaged to determine the vessel’s draft. Traditional static draft measurement techniques were also employed as a substitute for the WaterLOG H3611 measurements when required.Refer to DAPR for major systems used.Crosslines were planned and well distributed throughout the survey to ensure adequate quality control. Total crossline length surveyed was 26.03 nautical miles or 4.67 percent of the total mainscheme line length. Each crossline was compared to the entire mainscheme line plan through a 2m CUBE surface using the CARIS HIPS QC report routine. If the crossline covered an area with significantly rocky topography, the crossline was compared to a 1m CUBE surface of the entire mainscheme line plan. The majority of the QC Reports fall well within the required accuracy specifications. However, several crosslines run by survey vessel D2 in the area from Reef Point to North Head contain beams in the QC report that fall below the 95% confidence level due to significantly rocky topography as illustrated in the crossline profile from H12548. Good conformity was still seen between the mainscheme lines and the crosslines. H12548 Crossline Profilefile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Priority_6_Profile%20of%202P6B08-TIE01.png0.10.2Ocean Pioneer1.79700.250R200.4390.250D201.1010.250The majority of the data fell within IHO Order 1a accuracy specifications. Nodes that exceeded the allowable specifications were located in rough or rapidly changing topography or areas where the outer beams of the coverage boundaries were the single contributor to the surface. Despite the higher uncertainty values in these areas, agreement between adjacent lines and co-linearity between soundings was good. Note: The percentage of nodes within IHO Order 1a, were computed by CARIS using the Surface QC Report utility and are as follows: CUBE Surface Uncertainty Report Surface Depth Range (m) % of nodes within IHO Order 1a H12548-1m_Final 0 - 20 95.37% H12548-2m_Final 18 - 40 99.62% H12548-4m_Final 36 - 80 99.99% H12548-8m_Final 72 - 160 100.00% As illustrated in the uncertainty errors graphic, the uncertainty is generally lowest near the sonar nadir beams and increases toward the outside of each swath. This is expected and primarily a result of the sonar’s device model used within CARIS HIPS for TPU calculations. In general, total propagated uncertainty varies proportionally to water depth. Outer beams also have higher uncertainty values as a function of the bottom-detection algorithms within the sonar. Data met project specifications.H12548 Uncertaintyfile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Priority_6_H12548_Uncertainty.pngH12548 Uncertainty Errorsfile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Priority_6_H12548_Uncertainty_Errors.pngTVU values exceed IHO budgets in nearshore areas with higher frequency than usual. In the DAPR, section B, the surveyor indicates that the following values were entered into the CARIS 'Compute TPU box: Measured Tidal Uncertainty: 0.1m and Tidal Zoning Uncertainty: 0.2m. It is also indicated that these values were based on the HSSD 2012 which itself states that "An estimate for a typical processing error is 0.10 m at the 95% confidence level...." and ..."Estimates for typical errors associated with tidal zoning are 0.20 m at the 95% confidence level." Since CARIS expects these values to be input at the 68% CI level, the surveyor has effectively doubled the TVU associated with tides. This doubling of the tidal constituent of TVU is consistent with frequency with which the TVU budget was exceeded in nearshore areas. In review - and without any re-evaluation of TVU values based on the above findings - the number of nodes in the 1m surface meeting IHO order 1a TVU budget was found to be 95.25%. This acceptable percentage disagrees with the documented uncertainty report.The surveys are in agreement along their common borders. The conformity between H12548 and the bordering survey area (H12549) was inspected during processing, using CARIS HIPS’ Subset Editor routine and finalized BASE Surfaces. Difference surfaces were also created at a 4-meter resolution between H12548 and the junction with survey area H12361 (2011), the junction with survey area W00225 (2011), and the junction with the 5-meter surface from H11713 (2007). The data were well within the IHO Order 1a allowable error.H12361100002011Fugro Pelagos, Inc.EA difference surfaces was created at a 4-meter resolution between H12548 and the junction with survey area H12361 (2011), confirming that approximately 68.57% of the nodes agree to within +/-0.50m. The other 31.43% were on the outer edges of the swath at the coverage boundaries or were in areas with dynamic topography. The data were well within the IHO Order 1a allowable error. The southern portion of the junction area between H12548 and H12361 exhibited characteristics of a dynamic bottom. From the 2011 survey of H12361 to the 2013 survey of H12548, sediment appears to have eroded and deposited in specific sub-localities, as shown in the image provided. The hydrographer attempted to locate rocks or other fixed features in the junction area exhibiting this dynamic bottom; however, no rocks or fixed features were available to provide support for the claim that the differences between the two surveys are indeed due to a dynamic bottom. However, the hydrographer believes the differences are caused by dynamic bottom due to a) the sandy bottom type, b) the tide rips in the area, as indicated on NOAA’s raster chart 16531, and c) the strong agreement between the survey data in the northern portion of the survey junction area.H12548 Junctions with H12361file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/H12361_Junction_With_H12548.pngDifference Surface H12548 vs. H12361file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Diff_Surf_H12548-H12361_Overview_Annotated.pngDifference Surface Statistics H12548 vs. H12361file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Diff_Surf_Statistics_H12548-H12361_Ogive.pngW00225400002011Fugro Pelagos, Inc.NEA difference surface was created at a 4-meter resolution between H12548 and the junction with survey area W00225 (2011), confirming that approximately 99.11% of the nodes agree to within +/-0.50m. The other 0.89% were on the outer edges of the swath at the coverage boundaries. The data were well within the IHO Order 1a allowable error.H12548 Junctions with W00225file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/W00225_Junction_With_H12548.pngDifference Surface H12548 vs. W00225file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Diff_Surf_H12548-W00225_Overview_Annotated.pngDifference Surface Statistics H12548 vs. W00225file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Diff_Surf_Statistics_H12548-W00225_Ogive.pngH11713100002007Fugro Pelagos, Inc.SA difference surface was created to compare the 4-meter surface from H12548 and the junction with the 5-meter surface from H11713 (2007), confirming that approximately 96.57% of the nodes agree to within +/-0.50m. The other 3.43% were on the outer edges of the swath at the coverage boundaries or were located in areas with rocky topography. The data were well within the IHO Order 1a allowable error.H12548 Junctions with H11713file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/H11713_Junction_With_H12548.pngDifference Surface H12548 vs. H11713file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Diff_Surf_H12548-H11713_Overview_Annotated.pngDifference Surface Statistics H12548 vs. H11713file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Diff_Surf_Statistics_H12548-H11713_Ogive.pngA concurrent junction is also made with H12549 to the north, OPR-Q191-KR-13, 1:40,000. The junction with survey H12549 was completed during the SAR. A difference surface was generated between the 8 meter combined surfaces from both surveys and the difference are generally within 1 meter in depths greater than 85 meters, which is well within IHO specifications. The areas that show greater differences are deep areas, the outer edge of swath coverage and areas of dramatic topography, which is to be expected.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.KelpAlong coastal regions of the survey, an abundance of kelp was observed during data acquisition. Due to data quality and safety issues, there may be some areas where survey operations were halted, thus not achieving the 4 fathom survey limit. In addition to this, during data processing every effort was made to flag the kelp as rejected data wherever the CUBE BASE surface included the kelp as part of the seafloor.Sound Speed Refraction ErrorsSound speed refraction errors were seen in the outer beams of the swaths of survey lines that were run in deeper water. However, line overlap was sufficient, and the affected soundings were rejected in CARIS HIPS’ Subset Editor routine to ensure the CUBE surface met IHO Order 1a specifications.Sound speed measurements were conducted and applied as discussed in the Corrections to Echo Soundings section of the DAPR.All equipment and survey methods were used as detailed in the DAPR.Data DensityThe NOS Hydrographic Surveys Specifications and Deliverables, April 2012, requires 95% of all nodes to be populated with at least five soundings. Survey H12548 met these project specifications. Density requirements for H12548 were achieved with at least 99.72% of finalized surface nodes containing five or more soundings. Nodes that failed to meet the allowable specifications were located in rough or rapidly changing topography or areas where the outer beams of the coverage boundaries were the single contributor to the surface. CUBE Surface Density Report Surface Depth Range (m) % of nodes within HSSD 2012 H12548-1m_Final 0 - 20 99.73% H12548-2m_Final 18 - 40 99.96% H12548-4m_Final 36 - 80 99.94% H12548-8m_Final 72 - 160 99.85% Detection requirements were met by minimizing vessel speed when necessary, using sonar range scales appropriate to the water depth to maximize ping rates, and maximizing swath overlap. These variables were adjusted in real-time by the online acquisition crew based on the WinFrog QC and coverage displays. The shipboard processing crew provided feedback after preliminary processing and coverage creation in CARIS HIPS and In-fills were run as necessary.H12548 Data Densityfile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/Priority_6_H12548_Data_Density.pngAll data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Towed Side Scan Sonar (SSS) operations were not required by this contract, but the backscatter and beam imagery snippet data from all multibeam systems were logged and are stored in the s7k files. All beam imagery snippet data was logged in the 7028 record of the s7k file for the project.Version 5.3.2H12548_1mCUBE1099NOAA_1mComplete MBESH12548_1m_FinalCUBE1020NOAA_1mComplete MBESH12548_2mCUBE2099NOAA_2mComplete MBESH12548_2m_FinalCUBE21840NOAA_2mComplete MBESH12548_4mCUBE4099NOAA_4mComplete MBESH12548_4m_FinalCUBE43680NOAA_4mComplete MBESH12548_8mCUBE8099NOAA_8mComplete MBESH12548_8m_FinalCUBE872160NOAA_8mComplete MBESThe surfaces have been reviewed where noisy data, or 'fliers' are incorporated into the gridded solution causing the surface to be shoaler than the true seafloor. Where these spurious soundings cause the gridded surface to be shoaler than the reliably measured seabed by greater than the maximum allowable TVU at that depth, the noisy data have been rejected and the surface recomputed. The NOAA CUBE parameters mandated in HSSD were used for the creation of all CUBE BASE surfaces in Survey H12548.Additional information discussing the vertical and horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterDiscrete ZoningUnalaska, Dutch Harbor9462620King Cove9459881Broad Bight9462676SE Tigalda Island9462705Green Bight94627869462676.tid Verified Observed9462705.tid Verified Observed9462786.tid Verified ObservedOPR-Q191-KR-13_Zoning_20131008.zdf Preliminary2013-10-242013-10-31On October 08, 2013, John Oswald and Associates (JOA) issued verified tidal data and zoning for OPR-Q191-KR-13. All sounding data was then re-merged using CARIS HIPS and SIPS tide routine. JOA verified tidal data were used for all final Navigation BASE surfaces and S-57 Feature files. It should be noted that the tidal data applied to OPR-Q191-KR-13 is JOA verified and not CO-OPs verified. JOA are currently in the WALI verification process, which is pending, awaiting CO-OPs approval. Since the timeframe for CO-OPs verification is unknown, FPI were given approval, by our COTR, to submit the data with the JOA verified tides and zoning applied.JOA zoning model was approved as final by CO-OPs and zoning validation received January 30, 2014.NAD833NSingle BaseBroad BightBB_ESE Tigalda IslandTI_N For real-time DGPS corrections, a CSI MBX-3 unit was tuned to the Cold Bay, Alaska USCG DGPS site. The unit output differentially corrected positions at 1 Hz to the (POS MV) 320 V4 where it was integrated with inertial data, and a position for the top-center of the IMU generated. This position was logged concurrently with the bathymetry from WinFrog and the POS file using Fugro Pelagos PosMvLogger. It was later corrected for offsets to the multibeam echosounder (MBES) by CARIS HIPS in post-processing. Final positioning was done using post-processed kinematic (PPK) methods. Applanix POSPac MMS v5.4 software was used in conjunction with the POS files and local 1Hz base station data to generate a higher accuracy position, which was applied in processing to replace the real-time position records. SBET is not applied to lines 2P6B07-SH110, 2P6B06-INF03, 2P6B06-INF01, 2P6B06-INF04, 2P6B06-INF02, 1P6B10-1220, 2P6B06-TIE02, 2P6B06-TIE01, 2P6B06-TIE03 SBET RMS is not applied to lines 2P6B07-SH110, 2P6B06-INF03, 2P6B06-INF01, 2P6B06-INF04, 2P6B06-TIE02, 2P6B06-TIE01, 1P6B11-0080, 1P6B11-1140, 1P6B11-0565, 1P6B11-1300, 1P6B11-1460, 1P6B11-1560, 1P6B11-1680, 1P6B11-1990A, 1P6B11-1380, 1P6B11-0325, 1P6B11-0770, 1P6B11-0965, 1P6B11-1990, 1P6B11-1800, 1P6B11-1910, 2P6B07-SH099, 2P6B07-SH103, 2P6B07-SH100, 2P6B07-SH104, 2P6B07-SH106, 2P6B07-SH101, 2P6B07-SH105, 2P6B07-SH102, 2P6B07-SH107, 2P6B07-SH109, 2P6B07-SH108, 2P6B07-SH110Cold Bay DGPS Station1653118000072002-022013-10-012013-09-28The Raster chart was downloaded from NOAA’s Office of Coast Survey website on October 9, 2013. Given that the survey area was ensonified with 100% multibeam coverage, discrepancies were discovered between the charted and surveyed depths. Sounding agreement between surveyed soundings on sheet H12548 and spot soundings displayed on Raster chart 16531 varied between 1 and 3 fathoms. Generally, the surveyed data in the vicinity of the charted spot soundings from Raster chart 16531 agree to within 1 to 2 fathoms. The Hydrographer recommends that soundings within the survey limits of H12548 supersede all prior survey and charted depths.Chart Comparison H12548 vs. 16531file:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/H12548_vs_16531.pngIn addition, chart 16520, 1:300,000, ED 23, which coincides with ENC US4AK6FM, covers the western quarter of the survey. Chart 16520 was not listed in the PI for comparison, so the field wasn't required to address it.US3AK61M300000162011-01-122013-06-24falseThe ENCs were downloaded from NOAA’s Office of Coast Survey website on October 9, 2013. Thus, the issue dates displayed in the table above are more recent than the dates in the Project Instructions. Given that the survey area was ensonified with 100% multibeam coverage, discrepancies were discovered between the charted and surveyed depths. Sounding agreement between surveyed soundings on sheet H12548 and spot soundings displayed on ENC US3AK61M varied between 1 meter and 8 meters. Generally, the surveyed data in the vicinity of the charted spot soundings from the ENC agreed to within 1 to 5 meters. Although the ENC displays the spot soundings in meters, the contours are displayed in fathoms. The surveyed data for sheet H12548 shows contours that generally agree with the contour trends from ENC US3AK61M. The Hydrographer recommends that soundings within the survey limits of H12548 supersede all prior survey and charted depths.Chart Comparison H12548 vs. US3AK61Mfile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/H12548_vs_US3AK61M.pngUS4AK6FM8000082011-04-282013-05-02falseGiven that the survey area was ensonified with 100% multibeam coverage, discrepancies were discovered between the charted and surveyed depths. Sounding agreement between surveyed soundings on sheet H12548 and spot soundings displayed on ENC US4AK6FM varied between 1 meter and 5 meters. Although the ENC displays the spot soundings in meters, the contours are displayed in fathoms. The surveyed data for sheet H12548 shows contours that generally agree with the contour trends from ENC US4AK6FM. The Hydrographer recommends that soundings within the survey limits of H12548 supersede all prior survey and charted depths.Chart Comparison H12548 vs. US4AK6FMfile:///M:/OPRQ191KR13/Surveys/H12548/Compilation/Report/Support%20Files/H12548_vs_US4AK6FM.pngNo AWOIS items exist for this survey.No Maritime Boundary Points were assigned for this survey.No charted features exist for this survey.Charted features exist, but no charted features that contain the chart label PA, ED, PD or Rep exist for this survey.No uncharted features exist for this survey.No uncharted wrecks or obstructions, or other features from miscellaneous sources, exist for this survey.2H12548_DTON__Fugro_(07-21-13)2013-07-21Danger to Navigation Reports are included in Appendix I of this report. During field operations for survey OPR-Q191-KLR-13, four DTONs were submitted on H12548, but only two met NOAA criteria.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.Bottom samples were acquired per the Project Instructions.Shoreline was not assigned in the Hydrographic Survey Project Instructions or Statement of Work.Limited shoreline verification was assigned in the Project Instructions, including the instruction to verify all features with asgnmt attributed 'Assigned' regardless if it is located inshore of the Navigable Area Limit Line. In email with the COTR for a concurrent survey, this requirement was eased to allow the hydrographer discretion in selecting safe, navigationally significant features for field verification.No prior survey comparisons exist for this survey.One aid to navigation exists on the charts for H12548. The charted aid to navigation was found to be serving its intended purpose: 1. FI 6s 60ft 6M at N54-13-16, W165-58-50 No uncharted aids to navigation were found in the survey area. Overhead features do not exist for this survey.Submarine features do not exist for this survey.No ferry routes or terminals exist for this survey.No platforms exist for this survey.No significant features exist for this survey.There is no present or planned construction or dredging within the survey limits.Final Feature FileCharted features that fell inshore of the 4-fathom contour (NALL) were not investigated and have been noted with a “Not Addressed” comment in the “descrp” attribute of the final features file. Features that fell within the survey limits were addressed and attributed appropriately. This file contains the object and metadata with extended attributes as required in the Specifications and Deliverables (April 2012). All features, including ones from the NOAA assigned feature file, that were within the geographical bounds of H12548 are included in the “H12548_Field_Features.000” file. Note: Since CARIS Notebook and Bathy DataBASE were unable to export to S-57 with the parameters outlined in section 8.2 of the HSSD 2012, an additional text file with the required meta information was sent to accompany the S-57 file. There were numerous rocks and islets that were covered by multibeam, but not addressed.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, Standing and 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.Dean MoylesSenior Hydrographer (ACSM Cert. No. 226) 2013-11-04Data Acquisition and Processing Report2013-11-04Horizontal and Vertical Control Report2013-11-04MAR-P-001-R2 MBES Acquisition Procedures2013-11-04DAC-P-010-R3 MBES Processing Procedures2013-11-04Tides and Water Levels Package2013-11-04