<?xml version="1.0" encoding="utf-8"?>
<dr:descriptiveReport xmlns:dr="http://svn.pydro.noaa.gov/2022/01/DescriptiveReport" xmlns:hsd="http://svn.pydro.noaa.gov/2022/01/AllGlobalTypes" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://svn.pydro.noaa.gov/2022/01/DescriptiveReport http://svn.pydro.noaa.gov/2022/01/DR.xsd">
    <dr:metadata>
        <dr:projectMetadata>
            <hsd:number>OPR-E347-KR-22</hsd:number>
            <hsd:name>Central Chesapeake Bay, MD</hsd:name>
            <hsd:generalLocality>Central Chesapeake Bay</hsd:generalLocality>
            <hsd:fieldUnit>Leidos</hsd:fieldUnit>
        </dr:projectMetadata>
        <dr:registryMetadata>
            <hsd:registryNumber>H13511</hsd:registryNumber>
            <hsd:sheetID>1</hsd:sheetID>
            <hsd:registryInstructions xsi:nil="true" />
            <hsd:sublocality>Chesapeake Beach to Horseshoe Point</hsd:sublocality>
            <hsd:stateOrTerritory>Maryland</hsd:stateOrTerritory>
            <hsd:country>United States</hsd:country>
            <hsd:scale>20000</hsd:scale>
        </dr:registryMetadata>
        <dr:surveyMetadata>
            <hsd:year>2023</hsd:year>
            <hsd:chiefOfParty>Paul L. Donaldson</hsd:chiefOfParty>
            <hsd:projectType>Basic Hydrographic Survey</hsd:projectType>
            <hsd:PIDate>2022-08-23</hsd:PIDate>
            <hsd:datesOfSurvey>
                <hsd:start>2022-10-13</hsd:start>
                <hsd:end>2023-04-24</hsd:end>
            </hsd:datesOfSurvey>
            <hsd:equipmentTypes>
                <hsd:soundingEquipment>Multibeam Echo Sounder</hsd:soundingEquipment>
                <hsd:imageryEquipment>Side Scan Sonar</hsd:imageryEquipment>
                <hsd:imageryEquipment>Multibeam Echo Sounder Backscatter</hsd:imageryEquipment>
            </hsd:equipmentTypes>
            <hsd:acquisition>
                <hsd:units>meters</hsd:units>
            </hsd:acquisition>
            <hsd:timeZone>UTC</hsd:timeZone>
            <hsd:verifier>Atlantic Hydrographic Branch</hsd:verifier>
            <hsd:titlesheetRemarks>
                <hsd:fieldRemarks>Contract: 1305M220DNCNJ0056/TO-0003. 
Contractor: Leidos, 221 Third Street, Newport, RI 02840 USA. 
Subcontractors: Northstar Marine, Inc., 36 Clermont Drive, Clermont, NJ 08210; OARS, 8705 Shoal Creek Blvd, Suite 109, Austin, TX 78757. 
Leidos Doc. 22-TR-021. 
All times were recorded in UTC. 
Final data are corrected to North American Datum of 1983 (NAD83) 2011 realization 2010 (NAD83(2011)2010.0), UTM Zone 18N.</hsd:fieldRemarks>
                <hsd:branchRemarks>Any revisions to the Descriptive Report (DR) applied during office processing are shown in red italic text. The DR is maintained as a field unit product, therefore all information and recommendations within this report are considered preliminary unless otherwise noted. The final disposition of survey data is represented in the NOAA nautical chart products. All pertinent records for this survey are archived at the National Centers for Environmental Information (NCEI) and can be retrieved via https://www.ncei.noaa.gov/. Products created during office processing were generated in NAD83 UTM 18N, MLLW. All references to other horizontal or vertical datums in this report are applicable to the processed hydrographic data provided by the field unit.</hsd:branchRemarks>
            </hsd:titlesheetRemarks>
        </dr:surveyMetadata>
        <dr:dataLicense>
            <hsd:classification>CC0-1.0 (NOAA Contractors)</hsd:classification>
            <hsd:spdx>
                <hsd:licenseIdentifier>CC0-1.0</hsd:licenseIdentifier>
                <hsd:licenseDeed>https://creativecommons.org/publicdomain/zero/1.0/</hsd:licenseDeed>
                <hsd:legalCode>https://creativecommons.org/publicdomain/zero/1.0/legalcode</hsd:legalCode>
            </hsd:spdx>
            <hsd:description>These data were produced under contract with NOAA and any potential copyright was assigned to NOAA. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0).</hsd:description>
        </dr:dataLicense>
        <dr:assignment>Contractor</dr:assignment>
    </dr:metadata>
    <dr:areaSurveyed>
        <dr:areaDescription>
            <hsd:discussion>H13515 was located within the Central Chesapeake Bay, Maryland within Prospect Bay (Figure 1). The survey was conducted in accordance with coverage requirements listed in the Project Instructions (PI) OPR-E347-KR-22. 
</hsd:discussion>
            <hsd:limits>
                <hsd:northWest>
                    <hsd:latitude hemisphere="N">38.845484</hsd:latitude>
                    <hsd:longitude hemisphere="W">76.553606</hsd:longitude>
                </hsd:northWest>
                <hsd:southEast>
                    <hsd:latitude hemisphere="N">38.682539999999996</hsd:latitude>
                    <hsd:longitude hemisphere="W">76.448265</hsd:longitude>
                </hsd:southEast>
            </hsd:limits>
            <hsd:images>
                <hsd:caption>H13511 Survey Bounds</hsd:caption>
                <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_01.png</hsd:link>
            </hsd:images>
            <hsd:comments />
        </dr:areaDescription>
        <dr:surveyLimits>
            <hsd:results deviation="true">
                <hsd:discussion>Survey limits were acquired in accordance with the requirements in the Project Instructions and the Hydrographic Survey Specifications and Deliverables (HSSD), March 2022.
</hsd:discussion>
            </hsd:results>
            <hsd:comments />
        </dr:surveyLimits>
        <dr:surveyPurpose>
            <hsd:topic>
                <hsd:discussion>The Chesapeake Bay is the largest estuary in North America and heavily trafficked by commercial and recreational vessels as tourism, fishing, and marine commerce are economically vital for the region. In addition to fishing and tourism traffic, commercial vessels transit through the project area to reach the Port of Baltimore, which is ranked as a top 15 port in container and tonnage, and a top 10 port for dry bulk.

The majority of the prior data in the project area spans from the 1880s to 1940s. The bathymetric data vintage coupled with numerous storms and hurricanes having potentially changed the seabed over the last century raises a need to survey the area. In addition, the Ever Forward container ship ran aground near the Craighill Channel in March 2022, and was removed after 35 days. 206,230 cubic yards of material was dredged and taken to Poplar Island. The data from this project will provide modern bathymetry for updating National Ocean Service nautical charting products improving the safety of maritime traffic and commerce as well as supporting the Seabed 2030 global mapping initiative. Survey data from this project is intended to supersede all prior survey data in the common area.
</hsd:discussion>
            </hsd:topic>
            <hsd:comments />
        </dr:surveyPurpose>
        <dr:surveyQuality>
            <hsd:adequacy>The entire survey is adequate to supersede previous data.</hsd:adequacy>
            <hsd:discussion>Leidos warrants only that the survey data acquired by Leidos and delivered to NOAA under Contract 1305M220DNCNJ0056 reflects the state of the sea floor in existence on the day and at the time the survey was conducted.

H13511 was surveyed in accordance with the following documents:
-1305M220DNCNJ0056 signed.pdf, received 23 August 2022
-Hydrographic Survey Specifications and Deliverables (HSSD), March 2022
-PRF.000, received 24 August 2022
-CSF.000, received 24 August 2022
-OPR-E347-KR-22 Project Brief, held 07 September 2022
</hsd:discussion>
            <hsd:comments />
        </dr:surveyQuality>
        <dr:surveyCoverage>
            <hsd:coverageRequirement>
                <hsd:waterDepth>Sheets 1, 3, 4, 5, 7, 8, and 9</hsd:waterDepth>
                <hsd:requiredCoverage>Complete Coverage (Refer to HSSD Section 5.2.2.3)</hsd:requiredCoverage>
            </hsd:coverageRequirement>
            <hsd:coverageRequirement>
                <hsd:waterDepth>Inshore limit to 8 meters water depth</hsd:waterDepth>
                <hsd:requiredCoverage>Sidescan may be acquired at an altitude of 6-20% of the range scale.</hsd:requiredCoverage>
            </hsd:coverageRequirement>
            <hsd:results deviation="true">
                <hsd:discussion>Leidos chose to achieve the coverage requirement using Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam). Survey coverage achieved was in accordance with the requirements in the Project Instructions and the HSSD (Figure 2). 

In many areas of H13511 the inshore limit of the Navigable Area Limit Line (NALL) was reached seaward of the assigned survey bounds. Leidos surveyed to the NALL as defined by HSSD Section 1.3.2; within the surveyed bounds. However, due to safety concerns for personnel and survey equipment, some areas were not fully covered with multibeam echo sounder (MBES) data to exactly the 3.5-meter depth contour. This was due limited vessel maneuverability around the shoal depth areas, at these discrete locations. In these areas the side scan sonar (SSS) swath extended shoreward of the MBES swath, and indicated that the seafloor continued to rise abruptly and in a manner that the vessel could not navigate over for further MBES coverage; while also indicating in the SSS data that there were no significant objects that would require individual cartographic representation.

</hsd:discussion>
                <hsd:images>
                    <hsd:caption>Final Bathymetry Coverage for H13511</hsd:caption>
                    <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_02.png</hsd:link>
                </hsd:images>
            </hsd:results>
            <hsd:comments />
        </dr:surveyCoverage>
        <dr:coverageGraphic>
            <hsd:coverageGraphicImage />
        </dr:coverageGraphic>
        <dr:surveyStatistics>
            <hsd:LNM>
                <hsd:vesselLNM>
                    <hsd:vessel>
                        <hsd:hullID>R/V Sea Innovator I</hsd:hullID>
                        <hsd:statistics>
                            <hsd:MS_SBES>0.0</hsd:MS_SBES>
                            <hsd:MS_MBES>0.0</hsd:MS_MBES>
                            <hsd:MS_lidar>0.0</hsd:MS_lidar>
                            <hsd:MS_SSS>0.0</hsd:MS_SSS>
                            <hsd:MS_SBES_MBES>0.0</hsd:MS_SBES_MBES>
                            <hsd:MS_MBES_SSS>500.29</hsd:MS_MBES_SSS>
                            <hsd:MS_SBES_SSS>0.0</hsd:MS_SBES_SSS>
                            <hsd:XL_MBES_SBES>309.27</hsd:XL_MBES_SBES>
                            <hsd:XL_lidar>0.0</hsd:XL_lidar>
                        </hsd:statistics>
                    </hsd:vessel>
                    <hsd:vessel>
                        <hsd:hullID>R/V Oyster Bay II</hsd:hullID>
                        <hsd:statistics>
                            <hsd:MS_SBES>0.0</hsd:MS_SBES>
                            <hsd:MS_MBES>0.0</hsd:MS_MBES>
                            <hsd:MS_lidar>0.0</hsd:MS_lidar>
                            <hsd:MS_SSS>0.0</hsd:MS_SSS>
                            <hsd:MS_SBES_MBES>0.0</hsd:MS_SBES_MBES>
                            <hsd:MS_MBES_SSS>26.09</hsd:MS_MBES_SSS>
                            <hsd:MS_SBES_SSS>0.0</hsd:MS_SBES_SSS>
                            <hsd:XL_MBES_SBES>12.01</hsd:XL_MBES_SBES>
                            <hsd:XL_lidar>0.0</hsd:XL_lidar>
                        </hsd:statistics>
                    </hsd:vessel>
                </hsd:vesselLNM>
                <hsd:totalLNM>
                    <hsd:MS_SBES>0.0</hsd:MS_SBES>
                    <hsd:MS_MBES>0.0</hsd:MS_MBES>
                    <hsd:MS_lidar>0.0</hsd:MS_lidar>
                    <hsd:MS_SSS>0.0</hsd:MS_SSS>
                    <hsd:MS_SBES_MBES>0.0</hsd:MS_SBES_MBES>
                    <hsd:MS_MBES_SSS>809.45</hsd:MS_MBES_SSS>
                    <hsd:MS_SBES_SSS>0.0</hsd:MS_SBES_SSS>
                    <hsd:XL_MBES_SBES>38.1</hsd:XL_MBES_SBES>
                    <hsd:XL_lidar>0.0</hsd:XL_lidar>
                    <hsd:percentXLLNM>4.71</hsd:percentXLLNM>
                </hsd:totalLNM>
            </hsd:LNM>
            <hsd:totalSurveyStats>
                <hsd:bottomSamples>2</hsd:bottomSamples>
                <hsd:maritimeBoundaryPoints>0</hsd:maritimeBoundaryPoints>
                <hsd:DP>0</hsd:DP>
                <hsd:diveOps>0</hsd:diveOps>
                <hsd:SNM>24.49</hsd:SNM>
            </hsd:totalSurveyStats>
            <hsd:surveyDates>2022-10-13</hsd:surveyDates>
            <hsd:surveyDates>2022-10-14</hsd:surveyDates>
            <hsd:surveyDates>2022-10-15</hsd:surveyDates>
            <hsd:surveyDates>2022-10-16</hsd:surveyDates>
            <hsd:surveyDates>2022-10-17</hsd:surveyDates>
            <hsd:surveyDates>2022-10-18</hsd:surveyDates>
            <hsd:surveyDates>2022-10-19</hsd:surveyDates>
            <hsd:surveyDates>2022-10-21</hsd:surveyDates>
            <hsd:surveyDates>2022-11-03</hsd:surveyDates>
            <hsd:surveyDates>2022-11-04</hsd:surveyDates>
            <hsd:surveyDates>2022-11-05</hsd:surveyDates>
            <hsd:surveyDates>2022-11-07</hsd:surveyDates>
            <hsd:surveyDates>2022-11-09</hsd:surveyDates>
            <hsd:surveyDates>2022-12-10</hsd:surveyDates>
            <hsd:surveyDates>2022-12-11</hsd:surveyDates>
            <hsd:surveyDates>2022-12-13</hsd:surveyDates>
            <hsd:surveyDates>2022-12-16</hsd:surveyDates>
            <hsd:surveyDates>2022-12-17</hsd:surveyDates>
            <hsd:surveyDates>2023-04-10</hsd:surveyDates>
            <hsd:surveyDates>2023-04-11</hsd:surveyDates>
            <hsd:surveyDates>2023-04-24</hsd:surveyDates>
            <hsd:discussion xsi:nil="true" />
            <hsd:comments />
        </dr:surveyStatistics>
    </dr:areaSurveyed>
    <dr:dataAcquisitionAndProcessing>
        <dr:equipmentAndVessels>
            <dr:discussion>Leidos used their ISS-2000 software on a Windows platform to acquire these survey data. Survey planning and data analysis were conducted using the Leidos SABER software on Linux platforms. Side scan sonar (SSS) data were collected on a Windows platform using Klein’s SonarPro software. Subsequent processing and review of the SSS data, including the generation of coverage mosaics, were accomplished using SABER.

A detailed description of the systems and vessel used to acquire and process these data is included in the Data Acquisition and Processing Report (DAPR) for OPR-E347-KR-22, delivered concurrently with H13511. There were no variations from the equipment configuration described in the DAPR.
</dr:discussion>
            <dr:vessels>
                <dr:vessel>
                    <hsd:hullID>R/V Sea Innovator I</hsd:hullID>
                    <hsd:LOA units="feet">135.0</hsd:LOA>
                    <hsd:draft units="feet">9.0</hsd:draft>
                </dr:vessel>
                <dr:vessel>
                    <hsd:hullID>R/V Oyster Bay II</hsd:hullID>
                    <hsd:LOA units="meters">30.0</hsd:LOA>
                    <hsd:draft units="meters">3.0</hsd:draft>
                </dr:vessel>
                <dr:images>
                    <hsd:caption>R/V Sea Innovator I</hsd:caption>
                    <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_03.png</hsd:link>
                </dr:images>
                <dr:images>
                    <hsd:caption>R/V Oyster Bay II</hsd:caption>
                    <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_04.png</hsd:link>
                </dr:images>
                <dr:discussion>The R/V Sea Innovator I was used to collect multibeam echo sounder (MBES) (RESON SeaBat T50), side scan sonar (SSS) (Klein 4000), and sound speed data during twenty four hours per day survey operations. The R/V Oyster Bay II (Figure 4) was used to collect MBES (RESON SeaBat T50), SSS (Klein 4900), and sound speed data during twelve hours per day survey operations. 

A detailed description of the vessels used is included in the DAPR.


</dr:discussion>
                <dr:comments />
            </dr:vessels>
            <dr:equipment>
                <dr:majorSystem>
                    <hsd:type>MBES</hsd:type>
                    <hsd:manufacturer>Teledyne RESON</hsd:manufacturer>
                    <hsd:model>SeaBat T50-R</hsd:model>
                </dr:majorSystem>
                <dr:majorSystem>
                    <hsd:type>SSS</hsd:type>
                    <hsd:manufacturer>Klein Marine Systems</hsd:manufacturer>
                    <hsd:model>System 4000</hsd:model>
                </dr:majorSystem>
                <dr:majorSystem>
                    <hsd:type>SSS</hsd:type>
                    <hsd:manufacturer>Klein Marine Systems</hsd:manufacturer>
                    <hsd:model>System 4900</hsd:model>
                </dr:majorSystem>
                <dr:majorSystem>
                    <hsd:type>Positioning and Attitude System</hsd:type>
                    <hsd:manufacturer>Applanix</hsd:manufacturer>
                    <hsd:model>POS MV 320 v5</hsd:model>
                </dr:majorSystem>
                <dr:majorSystem>
                    <hsd:type>Sound Speed System</hsd:type>
                    <hsd:manufacturer>AML Oceanographic</hsd:manufacturer>
                    <hsd:model>BaseX</hsd:model>
                </dr:majorSystem>
                <dr:majorSystem>
                    <hsd:type>Conductivity, Temperature, and Depth Sensor</hsd:type>
                    <hsd:manufacturer>AML Oceanographic</hsd:manufacturer>
                    <hsd:model>MVP30</hsd:model>
                </dr:majorSystem>
                <dr:majorSystem>
                    <hsd:type>MBES Backscatter</hsd:type>
                    <hsd:manufacturer>Teledyne RESON</hsd:manufacturer>
                    <hsd:model>SeaBat T50-R</hsd:model>
                </dr:majorSystem>
                <dr:discussion>A detailed description of the equipment installed is included in the DAPR.
</dr:discussion>
                <dr:comments />
            </dr:equipment>
            <dr:comments />
        </dr:equipmentAndVessels>
        <dr:qualityControl>
            <dr:crosslines>
                <hsd:topic>
                    <hsd:discussion>Multibeam echo sounder crosslines acquired for this survey totaled 4.71% of mainscheme acquisition. The resulting crossline to mainscheme percentage met the requirement to achieve approximately four percent of mainscheme mileage for a complete coverage multibeam survey (Section 5.2.4.2 of the HSSD). H13511 requirements were for Complete Coverage, Option B, based on the classifications defined in Section 5.2.2.3 of the HSSD. 

The mainscheme lines were spaced 70 meters apart, and crosslines were generally spaced 1500 meters apart. In the field, hydrographers conducted daily comparisons of mainscheme to near nadir crossline data to ensure that no systematic errors were introduced and to identify potential problems with the survey systems. After the application of all correctors and completion of final processing in the office, separate CUBE PFM grids were built at 1-meter resolution for all data. One grid contained the full valid swath (±65° from nadir, Class 2) of mainscheme multibeam and the other included only the near nadir swath (±5° from nadir, Class 1) crossline data. The difference grid was created by subtracting the 1-meter H13511 mainscheme CUBE depths from the 1-meter H13511 crossline CUBE depths. Additional comparisons were conducted of each vessels mainscheme to crossline depth data. These results are summarized in Figure 5. 

The SABER Frequency Distribution Tool was used to analyze the difference grid created from the mainscheme and crossline PFM grids and the results of the analysis were compiled into the following section.

Section 5.2.4.2 of the HSSD states that the depth difference values are to be within the maximum allowable Total Vertical Uncertainty [TVU]. Of the three mainscheme to crossline analysis conducted the 100% of the comparisons were within TVU. Results for all crossing analysis are summarized in Figure 5.

As multiple vessels were used to survey H13511 repeatability analysis was performed between the data collected by both vessels where coincident. Of the vessel to vessel analysis, 99.99% of the comparisons were within TVU. Results are summarized in Figure 6. There were 51 comparisons which exceeded the maximum allowable TVU. In all instances, the differences were associated with features with the majority being associated with objects within the fish havens and fish weir piles. 

Results for analysis conducted are presented in Figure 7 to Figure 14.
</hsd:discussion>
                    <hsd:images>
                        <hsd:caption>Summary of Crossing Analysis</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_05.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Summary of Vessel Comparison Repeatability Analysis</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_06.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Tabular Results Crossing Analysis, Crosslines vs. Mainscheme Lines</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_07.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Crossing Analysis Crosslines vs. Mainscheme Lines</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_08.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Tabular Results Crossing Analysis, R/V Sea Innovator I Crosslines vs. Mainscheme Lines</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_09.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Crossing Analysis R/V Sea Innovator I Crosslines vs. Mainscheme Lines</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_10.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Tabular Results Crossing Analysis, R/V Oyster Bay II Crosslines vs. Mainscheme Lines</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_11.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Crossing Analysis R/V Oyster Bay II Crosslines vs. Mainscheme Lines</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_12.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Tabular Results Vessel Comparison Analysis, R/V Sea Innovator I vs. R/V Oyster Bay II</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_13.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Vessel Comparison Analysis R/V Sea Innovator I vs. R/V Oyster Bay II</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_14.png</hsd:link>
                    </hsd:images>
                </hsd:topic>
                <hsd:comments />
            </dr:crosslines>
            <dr:uncertainty>
                <hsd:values>
                    <hsd:tideUncertainty>
                        <hsd:tideMethod>ERS via VDATUM</hsd:tideMethod>
                        <hsd:measured units="meters">0.092</hsd:measured>
                        <hsd:zoning units="meters">0.2</hsd:zoning>
                    </hsd:tideUncertainty>
                    <hsd:soundSpeedUncertainty>
                        <hsd:hullID>R/V Sea Innovator I</hsd:hullID>
                        <hsd:measuredCTD units="meters/second">1</hsd:measuredCTD>
                        <hsd:measuredMVP units="meters/second">1</hsd:measuredMVP>
                        <hsd:measuredXBT units="meters/second">1</hsd:measuredXBT>
                        <hsd:surface units="meters/second">1</hsd:surface>
                    </hsd:soundSpeedUncertainty>
                    <hsd:soundSpeedUncertainty>
                        <hsd:hullID>R/V Oyster Bay II</hsd:hullID>
                        <hsd:measuredCTD units="meters/second">1</hsd:measuredCTD>
                        <hsd:measuredMVP units="meters/second">1</hsd:measuredMVP>
                        <hsd:measuredXBT units="meters/second">1</hsd:measuredXBT>
                        <hsd:surface units="meters/second">1</hsd:surface>
                    </hsd:soundSpeedUncertainty>
                </hsd:values>
                <hsd:discussion>For specific details on the use and application of the SABER Total Propagated Uncertainty (TPU) model, refer to the DAPR. Once the TPU model was applied to the GSF bathymetry data, each beam was attributed with the horizontal uncertainty and the vertical uncertainty at the 95% confidence level. The vertical and horizontal uncertainty values, estimated by the TPU model for individual multibeam soundings, varied little across the dataset, tending to be most affected by beam angle. Individual soundings that had vertical and horizontal uncertainty values above IHO S-44 6th Edition, Order 1a were flagged as invalid during the uncertainty attribution.

As discussed in the DAPR, SABER generates two vertical uncertainty surfaces; the Hypothesis Standard Deviation (Hyp. StdDev) and the Hypothesis Average Total Propagated Uncertainty (Hyp. AvgTPU). A third vertical uncertainty surface is generated from the larger value of these two uncertainties at each node and is referred to as the Hypothesis Final Uncertainty (Hyp. Final Uncertainty).

Per HSSD Section 5.2.2.3, H13511 depth data fell within one resolution surface (1-meter).

The final H13511 1-meter PFM CUBE surface contained final vertical uncertainties that ranged from 0.200 meters to 0.682 meters. The IHO Order 1a maximum allowable vertical uncertainty was calculated to range between 0.500 to 0.527 meters, based on the minimum CUBE depth (0.923 meters) and maximum CUBE depth (12.713 meters). Results from the SABER Check PFM Uncertainty function identified that there were nine nodes in the final H13511 1-meter PFM CUBE surface with final vertical uncertainties that exceeded IHO Order 1a allowable vertical uncertainty. Seven of the nodes were associated with scour around buoys, and the remaining two were associated with a steep ridge. A thorough review of the final gridded surface in post-processing showed no artifacts in the data and that all nodes which had an elevated CUBE uncertainty in the CUBE depth data agreed well with coincident data. The SABER Frequency Distribution Tool was also used to review the Hyp. Final Uncertainty surface within the final H13511 1-meter Main Area PFM grid. Results showed that 99.99% of all nodes had final uncertainties less than or equal to maximum allowable vertical uncertainty of 0.527 meters</hsd:discussion>
                <hsd:comments />
            </dr:uncertainty>
            <dr:junctions>
                <hsd:discussion>Per the Project Instructions, junction analysis was performed between H13511 and the surveys listed in the table below and illustrated in Figure 15. Results from the comparison to H13343, H13507, H13508, and H13510 are discussed below.

</hsd:discussion>
                <hsd:images>
                    <hsd:caption>General Locality of H13511 with Junctioning Surveys</hsd:caption>
                    <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_15.png</hsd:link>
                </hsd:images>
                <hsd:junction>
                    <hsd:survey>
                        <hsd:registryNumber>H13343</hsd:registryNumber>
                        <hsd:scale>20000</hsd:scale>
                        <hsd:year>2020</hsd:year>
                        <hsd:fieldUnit>Leidos</hsd:fieldUnit>
                        <hsd:relativeLocation>S</hsd:relativeLocation>
                    </hsd:survey>
                    <hsd:discussion>Junctioning survey H13343 was conducted in 2020 and junctions to the south of H13511. For this analysis the H13343 1-meter BAG depth surface was compared to the H13511 1-meter CUBE depth surface. Junction analysis was conducted on the common area of these two sheets, with an overlapping area approximately 4,410 by 405 meters along the southern edge of H13511. Observed depths within the common area were 1.356 to 10.786 meters which resulted in a calculated allowable TVU range of 0.500 to 0.519 meters. 

The difference grid was generated by subtracting the H13343 data from the H13511 data. Positive values indicate that H13511 depth data were deeper than H13343 depth data. Throughout the common area, H13511 CUBE depths were deeper 94.96% of the time and were shoaler 4.83% of the time (Figure 16) with 100% of the comparisons within 0.387. The distribution is skewed positive of zero as presented in Figure 17.

100.00% of the comparisons were 0.387 meters or less, within the calculated allowable TVU range.
</hsd:discussion>
                    <hsd:images>
                        <hsd:caption>Tabular Results Junction Analysis H13511 vs. H13343</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_16.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Junction Analysis H13511 vs. H13343</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_17.png</hsd:link>
                    </hsd:images>
                    <hsd:comments />
                </hsd:junction>
                <hsd:junction>
                    <hsd:survey>
                        <hsd:registryNumber>H13507</hsd:registryNumber>
                        <hsd:scale>20000</hsd:scale>
                        <hsd:year>2021</hsd:year>
                        <hsd:fieldUnit>NOAA Ship Thomas Jefferson</hsd:fieldUnit>
                        <hsd:relativeLocation>E</hsd:relativeLocation>
                    </hsd:survey>
                    <hsd:discussion>Junctioning survey H13507 was conducted in 2021 and junctions to the east of H13511. For this analysis the H13507 76-meter BAG depth surface was compared to the H13511 1-meter CUBE depth surface. Junction analysis was conducted on the common area of these two sheets, with an overlapping area approximately 17,970 by 550 meters along the entirety of the eastern edge of H13511. Observed depths within the common area were 8.259 to 11.774 meters which resulted in a calculated allowable TVU range of 0.511 to 0.523 meters. 

The difference grid was generated by subtracting the H13507 data from the H13511 data. Positive values indicate that H13511 depth data were deeper than H13507 depth data. Throughout the common area, H13511 CUBE depths were deeper 38.65% of the time and were shoaler 60.70% of the time (Figure 18). The distribution is well spread about zero for all comparisons as presented in Figure 19.

99.66% of the comparisons were 0.520 meters or less, within the calculated allowable TVU range.
</hsd:discussion>
                    <hsd:images>
                        <hsd:caption>Tabular Results Junction Analysis H13511 vs. H13507</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_18.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Junction Analysis H13511 vs. H13507</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_19.png</hsd:link>
                    </hsd:images>
                    <hsd:comments />
                </hsd:junction>
                <hsd:junction>
                    <hsd:survey>
                        <hsd:registryNumber>H13508</hsd:registryNumber>
                        <hsd:scale>5000</hsd:scale>
                        <hsd:year>2021</hsd:year>
                        <hsd:fieldUnit>NOAA Ship Thomas Jefferson</hsd:fieldUnit>
                        <hsd:relativeLocation>NE</hsd:relativeLocation>
                    </hsd:survey>
                    <hsd:discussion>Junctioning survey H13508 was conducted in 2021 and junctions to the northeast of H13511. For this analysis the NOAA provided H13508 BAG (H13508_MB_VR_MLLW_1of1.bag) depth surface was compared to the H13511 1-meter CUBE depth surface. Junction analysis was conducted on the common area of these two sheets, with an overlapping area approximately 320 by 430 meters along the northeastern corner of H13511. Observed depths within the common area were 8.287 to 10.538 meters which resulted in a calculated allowable TVU range of 0.511 to 0.518 meters. 

The difference grid was generated by subtracting the H13508 data from the H13511 data. Positive values indicate that H13511 depth data were deeper than H13508 depth data. Throughout the common area, H13511 CUBE depths were deeper 74.65% of the time and were shoaler 25.18% of the time (Figure 20). The distribution is skewed positive of zero for all comparisons as presented in Figure 21.

95.53% of the comparisons were 0.520 meters or less, within the calculated allowable TVU range</hsd:discussion>
                    <hsd:images>
                        <hsd:caption>Tabular Results Junction Analysis H13511 vs. H13508</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_20.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Junction Analysis H13511 vs. H13508</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_21.png</hsd:link>
                    </hsd:images>
                    <hsd:comments />
                </hsd:junction>
                <hsd:junction>
                    <hsd:survey>
                        <hsd:registryNumber>H13510</hsd:registryNumber>
                        <hsd:scale>5000</hsd:scale>
                        <hsd:year>2021</hsd:year>
                        <hsd:fieldUnit>NOAA Ship Thomas Jefferson</hsd:fieldUnit>
                        <hsd:relativeLocation>N</hsd:relativeLocation>
                    </hsd:survey>
                    <hsd:discussion>Junctioning survey H13510 was conducted in 2021 and junctions to the northeast of H13511. For this analysis the NOAA provided H13510 BAG (H13510_MB_VR_MLLW.bag) depth surface was compared to the H13511 1-meter CUBE depth surface. Junction analysis was conducted on the common area of these two sheets, with an overlapping area approximately 1770 by 370 meters along the northern edge of H13511. Observed depths within the common area were 2.324 to 10.538 meters which resulted in a calculated allowable TVU range of 0.501 to 0.518 meters. 

The difference grid was generated by subtracting the H13510 data from the H13511 data. Positive values indicate that H13511 depth data were deeper than H13510 depth data. Throughout the common area, H13511 CUBE depths were deeper 48.96% of the time and were shoaler 50.73% of the time (Figure 22). The distribution was spread positive of zero for all comparisons as presented in Figure 23.

94.61% of the comparisons were 0.520 meters or less, within the calculated allowable TVU range.
</hsd:discussion>
                    <hsd:images>
                        <hsd:caption>Tabular Results Junction Analysis H13511 vs. H13510</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_22.png</hsd:link>
                    </hsd:images>
                    <hsd:images>
                        <hsd:caption>Plot of Junction Analysis H13511 vs. H13510</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_23.png</hsd:link>
                    </hsd:images>
                    <hsd:comments />
                </hsd:junction>
                <hsd:comments />
            </dr:junctions>
            <dr:sonarQCChecks>
                <hsd:results deviation="true">
                    <hsd:discussion>Sonar system quality control checks were conducted as detailed in the DAPR.</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:sonarQCChecks>
            <dr:equipmentEffectiveness>
                <hsd:results deviation="false">
                    <hsd:issue>
                        <hsd:title>None Exist</hsd:title>
                        <hsd:discussion>There were no conditions or deficiencies that affected equipment operational effectiveness.</hsd:discussion>
                        <hsd:comments />
                    </hsd:issue>
                </hsd:results>
                <hsd:comments />
            </dr:equipmentEffectiveness>
            <dr:factorsAffectingSoundings>
                <hsd:results deviation="true">
                    <hsd:issue>
                        <hsd:title>Additional Factors Affecting Soundings</hsd:title>
                        <hsd:discussion>Dense biological interference were observed during discrete areas and during various days of survey which required numerous holiday reruns. Additionally, throughout survey acquisition both commercial and recreational fishing activity was heavy causing fishing gear to be present in the MBES data and required deviations in the survey acquisition lines requiring numerous holiday reruns. The end result was that there were no significant impacts to the final sounding data.

</hsd:discussion>
                        <hsd:comments />
                    </hsd:issue>
                </hsd:results>
                <hsd:comments />
            </dr:factorsAffectingSoundings>
            <dr:soundSpeedMethods>
                <dr:castFrequency>On the R/V Sea Innovator I, the MVP30 was the primary system used to collect sound speed profile (SSP) data, and on the R/V Oyster Bay II, the AML BaseX2 was the primary system used to collect SSP data, refer to the DAPR for additional details. SSP data were obtained at intervals frequent enough to meet depth accuracy requirements. 
</dr:castFrequency>
                <dr:discussion>All sound speed profiles applied for online bathymetry data collection were acquired within 500 meters of the bounds of the survey area as specified in Section 5.2.3.3 of the HSSD.

Confidence checks of the sound speed profile casts were routinely conducted by comparing at least two consecutive casts taken with different SSP sensors. 

All individual SSP files are delivered with the H13511 data and are broken out into sub-folders, which correspond to the purpose of each cast. Also, all individual SSP files for H13511 have been concatenated into two separate files based on the purpose of the cast, provided in CARIS format files (.svp), and delivered under (H13511/Processed/SVP/CARIS_SSP) on the delivery drive. In accordance with HSSD Section 8.3.6, SSP files were also converted to NCEI format, as detailed in the DAPR, and provided as a separate delivery to NCEI. Refer to the DAPR for additional details.
</dr:discussion>
                <dr:comments />
            </dr:soundSpeedMethods>
            <dr:coverageEquipmentAndMethods>
                <hsd:results deviation="true">
                    <hsd:discussion>All equipment and survey methods are detailed in the DAPR.</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:coverageEquipmentAndMethods>
            <dr:additionalQualityControl>
                <hsd:issue>
                    <hsd:title>Multibeam Coverage Analysis</hsd:title>
                    <hsd:discussion>Leidos chose to achieve the complete coverage requirement using 100% side scan sonar coverage with concurrent multibeam bathymetry. To achieve this coverage, the SSS was set to 50-meter range scale, and main scheme survey lines were spaced at 70-meters to ensure 100% SSS coverage. Disproval areas were covered with 200% side scan coverage.

The SABER Gapchecker program was used to flag MBES data gaps within the CUBE surface. Additionally, the entire surface was visually scanned for holidays at various points during the data processing effort. Additional survey lines were run to fill any holidays that were detected as defined for complete coverage surveys in Section 5.2.2.3 of the HSSD and email correspondence dated 02-22-2023 (refer to Project Correspondence for additional details Bathymetric data and side scan sonar imagery were reviewed and bathymetric splits were acquired if deemed necessary per Hydrographer’s discretion, as noted in Section 5.2.2.1 of the HSSD.

A final review of the CUBE Depth surface for H13511 showed that there were no holidays as defined for complete coverage surveys in Section 5.2.2.3 of the HSSD. Any remaining three by three unpopulated nodes in the final MBES surfaces were along the outer swath data, beyond the side scan nadir coverage gap, and fully covered with 100% SSS coverage.

All final H13511 CUBE PFM grids were examined for the number of soundings contributing to the chosen CUBE hypotheses for each node by running SABER’s Frequency Distribution Tool on the Hypothesis Number of Soundings (Hyp. # Soundings) surface. The Hyp. # Soundings surface reports the number of soundings that were used to compute the chosen hypothesis. Analysis was conducted on the Hyp. # Soundings surface from all PFM grids to ensure that the requirements for complete coverage surveys, as specified in HSSD Section 5.2.2.3 were met. Within the final 1-meter CUBE PFM grid 99.52% of all nodes contained five or more soundings.

As noted in Section A.4, the assigned survey bounds were achieved across H13511 except where the inshore limit of the Navigable Area Limit Line (NALL) was reached or the shoreline bathymetry made it unsafe of equipment and crew to continue into shoaler depths.
</hsd:discussion>
                    <hsd:comments />
                </hsd:issue>
                <hsd:comments />
            </dr:additionalQualityControl>
        </dr:qualityControl>
        <dr:echoSoundingCorrections>
            <dr:corrections>
                <hsd:results deviation="false">
                    <hsd:discussion>All data reduction procedures conform to those detailed in the DAPR.</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:corrections>
            <dr:calibrations>
                <hsd:results deviation="false">
                    <hsd:discussion>All sounding systems were calibrated as detailed in the DAPR.</hsd:discussion>
                    <hsd:calibration xsi:nil="true" />
                </hsd:results>
                <hsd:comments />
            </dr:calibrations>
            <dr:additionalIssues>
                <hsd:comments />
            </dr:additionalIssues>
        </dr:echoSoundingCorrections>
        <dr:backscatter>
            <hsd:results acquired="true">
                <hsd:discussion>Side Scan Sonar (SSS) Coverage Analysis: For all details regarding SSS data processing, see the DAPR. Leidos chose to adhere to the coverage requirements in the Project Instructions using Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam). Leidos generated two separate coverage mosaics at 1-meter cell size resolution as specified in Section 8.2.1 of the HSSD (See section B.2.9 for additional information). The first 100% and second 100% coverage mosaics were independently reviewed using tools in SABER to verify data quality and swath coverage. The SABER Gapchecker routine was used to flag data gaps within each of the 100% SSS coverage mosaics. Additionally, the entirety of each SSS surface was visually scanned for holidays at various points during the data processing effort. Additional survey lines were run to fill any holidays that were detected. All coverage mosaics are determined to be complete and sufficient to meet the requirements contained within the PI and HSSD. Each 100 percent coverage mosaic is delivered as a single georeferenced raster file (datum of NAD-83) in floating point GeoTIFF format, as specified in Sections 8.2.1 and 8.3.3 in the HSSD.

Multibeam Echo Sounder Seafloor Backscatter: For all details regarding MBES backscatter acquisition and processing see the DAPR. Leidos generated a MBES backscatter at 2-meter cell resolution per vessel; per HSSD. The MBES backscatter mosaics were reviewed for data quality and coverage. The MBES backscatter data acquired were written to the GSF in real-time by ISS-2000 and are delivered in the final GSF files for this sheet under the Processed/Sonar_Data/H13511_MB directory. All MBES backscatter mosaics are determined to be complete and sufficient to meet the requirements contained within the PI and HSSD. The coverage mosaics are delivered as a single georeferenced raster file (datum of NAD-83) in floating point GeoTIFF format, as specified in Section 6.2.4.2 in the HSSD.

</hsd:discussion>
            </hsd:results>
            <hsd:comments />
        </dr:backscatter>
        <dr:dataProcessing>
            <dr:drSoftware>
                <dr:bathySoftware>
                    <dr:manufacturer>Leidos</dr:manufacturer>
                    <dr:name>SABER</dr:name>
                    <dr:version>5.4.1.6.1</dr:version>
                </dr:bathySoftware>
                <dr:imagerySoftware>
                    <dr:manufacturer>Leidos</dr:manufacturer>
                    <dr:name>SABER</dr:name>
                    <dr:version>5.4.1.6.1</dr:version>
                </dr:imagerySoftware>
                <dr:imagerySoftware>
                    <dr:manufacturer>QPS</dr:manufacturer>
                    <dr:name>FMGT</dr:name>
                    <dr:version>7.10.3</dr:version>
                </dr:imagerySoftware>
                <dr:featureObjectCatalog>NOAA Profile Version 2022</dr:featureObjectCatalog>
                <dr:discussion>The primary data processing software used for both bathymetry and imagery was SABER.</dr:discussion>
                <dr:comments />
            </dr:drSoftware>
            <dr:surfaces>
                <dr:surface>
                    <hsd:surfaceName>H13511_MB_1m_MLLW_Final</hsd:surfaceName>
                    <hsd:surfaceType>BAG</hsd:surfaceType>
                    <hsd:resolution units="meters">1</hsd:resolution>
                    <hsd:depthRange>
                        <hsd:min units="meters">0.923</hsd:min>
                        <hsd:max units="meters">12.713</hsd:max>
                    </hsd:depthRange>
                    <hsd:surfaceParameter>N/A</hsd:surfaceParameter>
                    <hsd:purpose>Complete coverage, Option B (100% side scan sonar coverage with concurrent multibeam)</hsd:purpose>
                </dr:surface>
                <dr:surface>
                    <hsd:surfaceName>H13515_SSSAB_1m_400kHz_900kHz_1of1</hsd:surfaceName>
                    <hsd:surfaceType>SSS Mosaic</hsd:surfaceType>
                    <hsd:resolution units="meters">1</hsd:resolution>
                    <hsd:depthRange>
                        <hsd:min xsi:nil="true" />
                        <hsd:max xsi:nil="true" />
                    </hsd:depthRange>
                    <hsd:surfaceParameter>N/A</hsd:surfaceParameter>
                    <hsd:purpose>First 100% SSS</hsd:purpose>
                </dr:surface>
                <dr:surface>
                    <hsd:surfaceName>H13515_SSSAB_1m_900kHz_2of2</hsd:surfaceName>
                    <hsd:surfaceType>SSS Mosaic</hsd:surfaceType>
                    <hsd:resolution units="meters">1</hsd:resolution>
                    <hsd:depthRange>
                        <hsd:min xsi:nil="true" />
                        <hsd:max xsi:nil="true" />
                    </hsd:depthRange>
                    <hsd:surfaceParameter>N/A</hsd:surfaceParameter>
                    <hsd:purpose>Second 100% SSS (Disproval coverage)</hsd:purpose>
                </dr:surface>
                <dr:surface>
                    <hsd:surfaceName>H13511_MBAB_2m_SeaInnovatorI_400kHZ_1of2</hsd:surfaceName>
                    <hsd:surfaceType>MB Backscatter Mosaic</hsd:surfaceType>
                    <hsd:resolution units="meters">2</hsd:resolution>
                    <hsd:depthRange>
                        <hsd:min xsi:nil="true" />
                        <hsd:max xsi:nil="true" />
                    </hsd:depthRange>
                    <hsd:surfaceParameter>N/A</hsd:surfaceParameter>
                    <hsd:purpose>Complete MBES</hsd:purpose>
                </dr:surface>
                <dr:surface>
                    <hsd:surfaceName>H13511_MBAB_2m_OysterBayII_300kHz_2of2</hsd:surfaceName>
                    <hsd:surfaceType>MB Backscatter Mosaic</hsd:surfaceType>
                    <hsd:resolution units="meters">2</hsd:resolution>
                    <hsd:depthRange>
                        <hsd:min xsi:nil="true" />
                        <hsd:max xsi:nil="true" />
                    </hsd:depthRange>
                    <hsd:surfaceParameter>N/A</hsd:surfaceParameter>
                    <hsd:purpose>Complete MBES</hsd:purpose>
                </dr:surface>
                <dr:discussion>Complete Coverage Section 5.2.2.3 of the HSSD requires 1-meter grid resolution for depths ranging from 0 meters to 20 meters. Leidos generated the CUBE PFM grids for H13511 at 1-meter resolution.

SABER populates the CUBE depth with either the node’s chosen hypothesis or the depth of a feature or designated sounding set by the hydrographer, which overrides the chosen hypothesis. The range of CUBE depths of the H13511 1-meter PFM grid were from 0.923 meters (3.028 feet; 0.210 meters TVU) to 12.713 meters (41.709 feet; 0.210 meters TVU). 

The final gridded bathymetry data are delivered in Bathymetric Attributed Grid (BAG) format. The BAG files were exported from the CUBE PFM grid as detailed in the DAPR.
</dr:discussion>
                <dr:comments>
                    <hsd:branchComment>
                        <hsd:comment>Disregard SSS mosaics in Table 12 of Section B.5.2 regarding survey H13515. Correct side scan sonar mosaics actually submitted to the branch are named as followed:
H13511_SSSAB_1m_400kHz_900kHz_1of1
H13511_SSSAB_1m_400kHz_900kHz_2of2</hsd:comment>
                    </hsd:branchComment>
                </dr:comments>
            </dr:surfaces>
            <dr:additionalDataProcessing>
                <hsd:comments />
            </dr:additionalDataProcessing>
        </dr:dataProcessing>
    </dr:dataAcquisitionAndProcessing>
    <dr:verticalAndHorizontalControl>
        <dr:discussion>In accordance with HSSD Section 2.2, the horizontal datum for this project is NAD83. HSSD Section 2.2 states that the “only exception for the NAD83 datum requirement is that the S-57 Final Feature File (Section 7.3) will be in the WGS84 datum to comply with international S-57 specifications”. As discussed in the DAPR Section C.7, for every feature flag in a MBES GSF file, SABER converts the position from the NAD83 datum to the WGS84 datum to generate the S-57 file and comply with HSSD and IHO requirements. Feature positions meet the precision stated in HSSD Section 7.4 for each respective datum. Depending on geographic reference there may be approximately a 1-meter difference comparing positions between NAD83 and WGS84 datums. Therefore, if the feature overrides from the BAG surface (NAD83) are compared to the Final Feature File S-57 positions (WGS84) it is anticipated that there could be positional differences exceeding those listed in Section 7.4 of the HSSD. Additional information discussing the vertical and horizontal control for this survey can be found in the DAPR.
</dr:discussion>
        <dr:verticalControl>
            <hsd:verticalDatum>Mean Lower Low Water</hsd:verticalDatum>
            <hsd:tideStations />
            <hsd:standard_or_ERZT xsi:nil="true" used="false" />
            <hsd:VDATUM_or_constantSep used="true">
                <hsd:methodsUsed>ERS via VDATUM</hsd:methodsUsed>
                <hsd:ellipsoidToChartDatumSepFile>
                    <hsd:fileName>OPR-E347-KR-22 _NAD83_VDatum_MLLW.cov</hsd:fileName>
                </hsd:ellipsoidToChartDatumSepFile>
                <hsd:discussion>Refer to the DAPR for details regarding the application of VDatum to the MBES data files. No final tide note was provided nor was it required from NOAA Center for Operational Oceanographic Products and Services (CO-OPS). 
</hsd:discussion>
                <hsd:comments />
            </hsd:VDATUM_or_constantSep>
            <hsd:comments />
        </dr:verticalControl>
        <dr:horizontalControl>
            <hsd:horizontalDatum>North American Datum 1983 (2011)</hsd:horizontalDatum>
            <hsd:projection>Projected UTM 18</hsd:projection>
            <hsd:PPK xsi:nil="true" used="false" />
            <hsd:PPP used="true">
                <hsd:discussion>The vessel kinematic data (POS/MV files) were post-processed in Applanix POSPac software using the Applanix PP-RTX solution to generate the Smoothed Best Estimate of Trajectory (SBET) solutions which were applied through SABER to the multibeam data. Refer to the DAPR for additional information and for details regarding all antenna and transducer offsets. Any soundings with total horizontal uncertainties exceeding the maximum allowable IHO S-44 6th Edition Order 1a specifications were flagged as invalid and therefore were not used in the CUBE depth calculations.
</hsd:discussion>
                <hsd:comments />
            </hsd:PPP>
            <hsd:RTK xsi:nil="true" used="false" />
            <hsd:DGPS xsi:nil="true" used="false" />
            <hsd:WAAS xsi:nil="true" used="false" />
            <hsd:comments />
        </dr:horizontalControl>
        <dr:additionalIssues>
            <hsd:comments />
        </dr:additionalIssues>
    </dr:verticalAndHorizontalControl>
    <dr:resultsAndRecommendations>
        <dr:chartComparison>
            <dr:methods>
                <hsd:topic>
                    <hsd:discussion>Chart comparisons were conducted using a combination of SABER and CARIS’ HIPS and SIPS. H13511 data met data accuracy standards and bottom coverage requirements. Leidos recommends updating the common areas of all charts using data from this survey. Review showed that the H13511 CUBE data were generally in agreement with charted depths compared to the ENCs listed in Section D.1.1. CUBE depths generally agreed with the charted depths within ±0.3-0.4 meters and were generally found to be deeper than charted.

Charting recommendations for new features and updates to charted features, are documented in the H13511 S-57 FFF. Additional charted objects are discussed in later sections.

United States Coast Guard (USCG) District 5 LNM publications were reviewed for changes subsequent to the date of the Project Instructions and before the end of survey. The LNM reviewed were from week 35/22 (30 August 2022) until week 24/23 (13 June 2023).
</hsd:discussion>
                </hsd:topic>
                <hsd:comments />
            </dr:methods>
            <dr:charts>
                <hsd:ENC>
                    <hsd:name>US5MD13M</hsd:name>
                    <hsd:scale>40000</hsd:scale>
                    <hsd:edition>32</hsd:edition>
                    <hsd:updateApplicationDate>2023-05-09</hsd:updateApplicationDate>
                    <hsd:issueDate>2023-05-09</hsd:issueDate>
                </hsd:ENC>
                <hsd:ENC>
                    <hsd:name>US5MD16M</hsd:name>
                    <hsd:scale>40000</hsd:scale>
                    <hsd:edition>34</hsd:edition>
                    <hsd:updateApplicationDate>2023-05-09</hsd:updateApplicationDate>
                    <hsd:issueDate>2023-05-09</hsd:issueDate>
                </hsd:ENC>
                <hsd:comments />
            </dr:charts>
            <dr:shoalAndHazardousFeatures>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>Refer to Figure 24 and Section D.1.4 for significant shoals or hazardous features within the area covered by this survey. Figure 24 details the Leidos submitted DTON reports for H13511. Reports were submitted per HSSD in S-57 format to the Atlantic Hydrographic Branch (AHB). 

</hsd:discussion>
                    <hsd:images>
                        <hsd:caption>DTON Reports</hsd:caption>
                        <hsd:link>file:///B:/OPR-E347-KR-22/Surveys/H13511/01_HDR/Reports/Descriptive_Report/SupportFiles/H13511_Figure_24.png</hsd:link>
                    </hsd:images>
                </hsd:results>
                <hsd:comments />
            </dr:shoalAndHazardousFeatures>
            <dr:chartedFeatures>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>There were numerous assigned charted features in the final CSF within the SOW of H13511. Per HSSD Section 8.1.4, these charted features are not addressed in this section, refer to the H13511 S-57 FFF (H13511_FFF.000) for all the details and recommendations regarding these features.

</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:chartedFeatures>
            <dr:unchartedFeatures>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>See the H13511 S-57 FFF for all the details and recommendations regarding new uncharted features investigated. During the course of H13511 survey operations, fishing gear in the form of fish weirs and temporary floats associated with crab pots were observed within the survey area. Due to the temporary nature of the crab floats, there are no features associated with these within the H13511 S-57 FFF. When a temporary fishing surface float was identified and correlated to objects in the MBES data, as these were not true seafloor the MBES data were invalidated and no longer contributed to a CUBE surface. In many cases, where it was not possible to confirm the fishing gear were not derelict or tied to a surface float, the object was retained in the MBES data. See Section B.2.5 for more information.

Exposed fish weir piles were present within the survey area as well as numerous submerged piles associated derelict fish weirs. Fish weirs are represented in the S-57 FFF as both point objects and area files based on their size and complexity.

</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:unchartedFeatures>
            <dr:channels>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>There were three channels assigned as dredge areas (DRGARE) within the H13511 SOW from the final CSF. All assigned dredge areas fell inshore of NALL and were not surveyed. 
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:channels>
        </dr:chartComparison>
        <dr:additionalResults>
            <dr:ATONS>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>There were no assigned Aids to Navigation (ATON) within the SOW of H13511 from the final CSF. All ATONs present within the survey area were present and serving their intended purpose. There were yellow HHSA sail race buoys present for part of the survey as well as “no shell fishing” and “clam line” buoys present. As these buoys are temporary in nature or repositioned frequently, they are not included in the H13511 S-57 FFF per the HSSD. Associated contacts are provided within the SSS Contacts S-57.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:ATONS>
            <dr:maritimeBoundary>
                <hsd:results investigated="None Exist">
                    <hsd:discussion>No Maritime Boundary Points were assigned for this survey.</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:maritimeBoundary>
            <dr:bottomSamples>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>In accordance with both the PI and Section 7.2.3 of the HSSD, bottom characteristics were obtained for H13511. Bottom characteristics were acquired at the four locations assigned in the final PRF. Leidos did not modify the bottom sample locations from the location proposed by NOAA in the PRF. Bottom characteristics are included in the S-57 FFF. In addition, images of the sediment obtained for each bottom sample are referenced in the S-57 FFF and are included on the delivery drive under the folder H13511/Processed/Multimedia.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:bottomSamples>
            <dr:overheadFeatures>
                <hsd:results investigated="None Exist">
                    <hsd:discussion>There were no overhead features within this survey area.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:overheadFeatures>
            <dr:submarineFeatures>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>Within the final CSF, there was one assigned submarine feature (PIPSOL) for investigation with a category of sewer. The charted pipeline was located inshore of NALL and covered by SSS for approximately 50 meters and covered by MBES for approximately 15 meters. No pipeline was identified however an obstruction was identified approximately 20 meters north of the charted pipeline. Refer to the H13511 FFF for details. No other uncharted or unburied pipelines were found within the H13511 survey data.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:submarineFeatures>
            <dr:platforms>
                <hsd:results investigated="Investigated">
                    <hsd:discussion>There were two assigned offshore platforms (OFSPLF) assigned in the CSF and are addressed in the H13511 FFF. Both were located inside of NALL and not covered during survey. One OFSPLF was visually confirmed as present. Refer to the H13511 FFF for details.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:platforms>
            <dr:ferryRoutesAndTerminals>
                <hsd:results investigated="None Exist">
                    <hsd:discussion>No ferry routes or terminals exist within this survey area.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:ferryRoutesAndTerminals>
            <dr:abnormalSeafloorEnviroCond>
                <hsd:results investigated="None Exist">
                    <hsd:discussion>No other abnormal seafloor or environmental conditions, as defined in Section 8.1.4 of the HSSD, exist within this survey area other than those discussed in Section B.2.5 and D.1.2.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:abnormalSeafloorEnviroCond>
            <dr:constructionOrDredging>
                <hsd:results investigated="None Exist">
                    <hsd:discussion>No construction or dredging exists within the assigned H13511 area.
</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:constructionOrDredging>
            <dr:newSurveyRecommendation>
                <hsd:results recommended="false">
                    <hsd:discussion>No new surveys or further investigations are recommended for this area.</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:newSurveyRecommendation>
            <dr:ENCScaleRecommendation>
                <hsd:results recommended="false">
                    <hsd:discussion>No new ENC scales are recommended for this area.</hsd:discussion>
                </hsd:results>
                <hsd:comments />
            </dr:ENCScaleRecommendation>
        </dr:additionalResults>
    </dr:resultsAndRecommendations>
    <dr:approvalSheet>
        <dr:statements>
            <dr:supervision>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.</dr:supervision>
            <dr:approval>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.</dr:approval>
            <dr:adequacyOfSurvey>The survey data meets or exceeds requirements as set forth in the Hydrographic Survey Specifications and Deliverables, Project Instructions, and Statement of Work. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required. Previously, or previously, submitted deliverables for OPR-E347-KR-22 are provided in the table below.
</dr:adequacyOfSurvey>
            <dr:additionalInfo xsi:nil="true" />
        </dr:statements>
        <dr:signingPersonnel>
            <hsd:approverName>Paul L. Donaldson</hsd:approverName>
            <hsd:approverTitle>Chief Hydrographer</hsd:approverTitle>
            <hsd:approvalDate>2023-07-17</hsd:approvalDate>
        </dr:signingPersonnel>
        <dr:additionalReports>
            <hsd:reportName>OPR-E347-KR-22 Final Project Summary Report.pdf</hsd:reportName>
            <hsd:reportDateSent>2023-05-31</hsd:reportDateSent>
        </dr:additionalReports>
        <dr:additionalReports>
            <hsd:reportName>OPR-E347-KR-22_Marine_Species_Awareness_Training_Record.pdf</hsd:reportName>
            <hsd:reportDateSent>2023-06-21</hsd:reportDateSent>
        </dr:additionalReports>
        <dr:additionalReports>
            <hsd:reportName>OPR-E347-KR-22_Coast Pilot Review Report.pdf </hsd:reportName>
            <hsd:reportDateSent>2023-06-22</hsd:reportDateSent>
        </dr:additionalReports>
        <dr:additionalReports>
            <hsd:reportName>OPR-E347-KR-22_DAPR.pdf</hsd:reportName>
            <hsd:reportDateSent>2023-07-17</hsd:reportDateSent>
        </dr:additionalReports>
    </dr:approvalSheet>
</dr:descriptiveReport>