There were 1152 charted features assigned for Survey H13385. Many of these were underwater rocks, which were represented by the bathymetry grid and not recommended for retention on the chart as individual features. Survey H13385 addressed 26 charted wrecks, and those found as point features with a length longer than 1mm at survey scale were replaced with area features. There were 55 area obstructions were assigned, many of which were beyond the NALL, but partial multibeam or vessel-mounted lidar coverage was achieved in some cases. See the FFF for details. There were 17 DTONs accepted for Survey H13385, all of which are included in the FFF. The rocky nature of the seafloor and the high vessel traffic have given this area a large number of potentially dangerous rocks and obstructions. Foul area obstructions are common within this survey, and their extents were not often covered with survey data due to their shallow depths. An evaluation of foul area obstructions based on aerial lidar data is recommended. Vessel-mounted lidar detected 52 new baring or exposed rocks, which were included as new features in the FFF as they represent hazards not fully covered by the bathymetry grid. There were an additional 13 new exposed rocks that had an elevation of more than 0.1m above MHW, which were made into new land area features with associated elevations. Docks and piers were also surveyed with vessel-mounted lidar; new features were added and existing features repositioned with survey data. Uncharted wrecks and obstructions surveyed with multibeam were made into new area features if they were longer than 10m, or 1mm at survey scale; features less than 10m in length were included as point features. See the FFF for details. 2021-02-0412021-02-0420000US5CT1AA2021-02-0412021-02-0420000US5HEPCB2021-02-04402021-02-0420000US5NY15M2021-02-04352021-02-0420000US5NY16MThere were 6 channels assigned in the CSF for Survey H13385. Of these, 3 were entirely beyond the NALL and 1 was mostly beyond the NALL, extending less than 150m into the surveyed area. The 2 channels addressed by this survey are Glen Cove Creek Channel and Hempstead Harbor Channel. The maintained depth of Glen Cove Creek Channel is 0.6m. Surveyed data was deeper than this for the length of the channel, with the exception of a small area near shore that the survey vessel was unable to reach due to water depths. Approximately 130m at the eastern end of the channel was also not surveyed, as the channel extended beyond our survey limits. Hempstead Harbor Channel has a maintained depth of 2.1m. Most of the channel is well below this depth, but the eastern edge of the channel is steep and survey data near the edge is slightly under 2.1m in places. Two small areas of the channel fell outside survey coverage.During the course of survey data collection and analysis, the Office of Coast Survey was actively implementing ENC rescheming in western Long Island Sound. The ENCs listed below provide complete coverage of the survey area and were the most recent charts available as of February 23, 2021. After this date, newly released ENCs were no longer considered in the chart comparison analysis for this survey. There were 7 bottom samples collected for Survey H13385. Two of the assigned sample locations were located within a charted cable area, and approval was given to change the location of these samples. See the Project Correspondence for details. No new surveys or further investigations are recommended for this area.Assigned overhead features in Survey H13385 included 1 bridge and 3 segments of an overhead cable. The bridge was well beyond the NALL and not investigated. The overhead cable was visually confirmed to exist as charted. No overhead clearance reports were submitted.The Iroquois Gas Transmission System pipeline is present as charted and runs approximately 10km across the width of the survey area in an east-west direction. A trench is visible in the bathymetry, but at no point did the pipeline itself appear exposed. A number of shorter exposed pipeline segments are included in the FFF and in the Non-DTON Pipeline Report; most are charted or within charted pipeline areas. There is 1 possible outfall pipe that is not charted. No abnormal seafloor or environmental conditions exist for this survey.No construction or dredging was observed within the survey limits.Based on the complexity of the shoreline and rocky areas, and the high traffic of recreational watercraft, OSI recommends that all charts within this survey be released at a 10,000 scale instead of the current 20,000 scale.No ferry routes or terminals exist for this survey.No platforms exist for this survey.No Maritime Boundary Points were assigned for this survey.All but 2 ATONS assigned in Survey H13385 were found to be on station and are documented in the FFF. There was 1 ATON missing and 1 that was off station from its charted position, both of which were reported to the USCG via their website. The off-station beacon structure was less than 2mm at chart scale from its charted position, and so is included in the FFF to be retained. Correspondence regarding these ATONS is included in Appendix II. There were 2 new ATONS surveyed, both signs marking no-wake zones. They were positioned with vessel-mounted lidar and included in the FFF with "For Info Only" in the recommendation field.Survey H13385 coverage overlaid on a composite of RNCs.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385-Survey-Coverage.jpgRV Able 20000045.4977.900RV Osprey000008.992.500RV Ready 20000028.1688.8000000082.44.681759.2002020-07-282020-07-292020-07-302020-07-312020-08-012020-08-022020-08-032020-08-052020-08-062020-08-072020-08-082020-08-092020-08-102020-08-112020-08-122020-08-132020-08-142020-08-152020-08-172020-08-182020-08-192020-08-202020-08-212020-08-222020-08-232020-08-242020-08-252020-08-262020-08-272020-08-292020-08-302020-09-012020-09-022020-09-032020-09-042020-09-092020-09-102020-09-112020-09-132020-09-152020-09-162020-09-172020-09-212020-09-232020-09-242020-09-252020-09-262020-10-162020-10-172020-10-182020-10-192020-10-202020-10-212020-12-117022.400The entire survey is adequate to supersede previous data.All waters in survey areaComplete Coverage (Refer to HSSD Section 5.2.2.3)All waters in survey areaAcquire backscatter data during all multibeam data acquisition (Refer to HSSD Section 6.2)Survey coverage was in accordance with the requirements listed above and in the HSSD.This survey provides hydrographic data for the waters of western Long Island Sound and Hempstead Harbor. The general locations of the survey limits are presented in Table 1.40.82162173.62030440.96574473.75927The following text is quoted from the Project Instructions' Purpose and Location section: As the second largest port in the U.S., handling more $187.3 billion in cargo in a year mostly of foreign imports (1), within one of most densely populated areas in the U.S. with 23.3 million people living within a 50-mile radius of Long Island Sound (2), the Port of New York / New Jersey stands as an important international commercial gateway to the U.S. As a result, increasing demand for larger cargo ships with ever deeper drafts demand precise and safe navigation. The primary purpose of this project is to provide contemporary hydrographic data to update National Ocean Service (NOS) nautical charting products and services in the U.S. that support commerce and water transportation in the regions of New York, New Jersey, and Connecticut. Data will inform scientific studies including Office of Coast Survey's precision navigation program, and the management and planning of state agencies and private consortia monitoring the health of benthic habitats and environmental quality of Long Island Sound (3). The survey area occupies 90 square nautical miles of estuarine water from the East River at Randalls Island, through Throgs Neck, and western Long Island Sound. Western Long Island Sound and the eastern portion of the East River were last surveyed in the late 1990s and early 2000s. Survey data from this project is intended to supersede all prior survey data in the common area. Sources: 1. U.S. Department of Transportation, Bureau of Transportation Statistics, Transportation Statistics Annual Report 2018 (Washington, DC: 2018). 2. Mackun, Paul; Wilson, Steven, "Population Distribution and Change: 2010 Census Briefs." U.S. Department of Commerce, Economics and Statistics Administration, U.S. Census Bureau, March 2011. http://longislandsoundstudy.net/wp-content/uploads/2010/08/c2010br-01.pdf. 3. Long Island Sound Research Collaborative, "Status and Trends LIS Environmental Indicators" Long Island Sound Study, http://longislandsoundstudy.net/2010/08/population-within-50-mile-radius-of-lis/. Accessed 23 January, 2020.Survey limits were acquired in accordance with the requirements in the Project Instructions and the HSSD.New York and ConnecticutOcean SurveysOPR-B300-KR-20Long Island SoundContractor2020-07-282020-12-11Navigable Areameters2020John R. BeanAny 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.Atlantic Hydrographic BranchUTC2020-06-26Multibeam Echo SounderMultibeam Echo Sounder BackscatterMamaroneck Harbor to Hempstead HarborUnited States10000New York2H13385All equipment was installed, calibrated, and operated in accordance with the DAPR.Teledyne RESONSeaBat T50-RMBESApplanixPOS MV 320 v5Positioning and Attitude SystemVelodyne LiDARVLP-16Lidar SystemTrimbleNetR9Positioning SystemAML OceanographicMicroX SVSound Speed SystemAML OceanographicBaseXSound Speed SystemAML OceanographicBaseX2Sound Speed SystemRefer 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.RV Able 20.47.6RV Osprey0.67.9RV Ready 20.47.6All sounding systems were calibrated as detailed in the DAPR.All data reduction procedures conform to those detailed in the DAPR.NOAA Profile Version 2020CARIS Raster Surface (CUBE)H13385_MB_50cm_MLLW_Final.csarComplete MBES-1.0238.0620.5NOAA_0.5mCARIS Raster Surface (CUBE)H13385_MB_50cm_MLLW.csarComplete MBES-1.0238.0620.5NOAA_0.5mMB Backscatter MosaicH13385_MBAB_2m_400kHz_1of1Processed Backscatter2N/AH13385 MBES surface uncertainty statisticsfile:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385_MB_50cm_Finalized.QAv6.tvu_qc.pngThe methods used to minimize the uncertainty in the corrections to echo soundings are described in detail in the project DAPR. The HydrOffice "QC Tools" application was used to calculate TVU QC, determined by a ratio of uncertainty to the allowable error per NOAA and IHO specifications. The finalized surface for Survey H13385 passed the uncertainty check, with 99.5+% of the nodes meeting uncertainty standards (Figure 4).RV Able 241RV Osprey41RV Ready 2410.09450ERS via VDATUMSonar 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.H13385 MBES surface data density statisticsfile:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385_MB_50cm_Finalized.QAv6.density.pngThis survey was conducted to achieve Complete Coverage with multibeam, as specified in HSSD 5.2.2.3, Option A. This calls for 100% bathymetric bottom coverage with multibeam sonars, and complete coverage multibeam developments of features. The survey methods used to meet coverage requirements did not deviate from those described in the DAPR. The HydrOffice "QC Tools" application was used to verify that the grid nodes met the density coverage requirements, with 99.5+% of the nodes meeting the requirement (Figure 8).None ExistThere were no other factors that affected corrections to soundings.An overview of crossline layout on a 1m surface created from mainscheme MBES data and colored by depth, with a composite image of RNCs in the background.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385-XL-overview.jpgA frequency distribution of the depth differences between H13385 crossline vs mainscheme MBES data. Statistics from the depth difference sample set are displayed above the graph.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385-mainscheme-vs-XL.jpgMultibeam crosslines acquired for this survey total 4.7% of mainscheme acquisition. Crosslines were collected on an ongoing basis throughout the survey as the vessels progressed through 7 geographic sections that were defined to assist with data management. Within each section the majority of the mainscheme data was collected over several consecutive days followed by 1-4 days of crossline acquisition. Figure 2 shows the layout of the crosslines within the survey. A difference surface was generated in CARIS HIPS comparing the crosslines to the mainscheme data, and a histogram of the depth differences was plotted to show the relative agreement of surveyed depths. Depth discrepancies were minimal, as shown in the histogram in Figure 3. Areas of greater difference include rocky regions near the shorelines. Sound speed profile data were acquired with the AML Base-X or AML Base-X2 at intervals of approximately 1-2 hours.Hydrographers acquired more frequent sound speed profiles if high variability was noted in the surface sound speed from the AML Micro-X installed on the head of the transducer, or when the surface sound speed comparison threshold was exceeded (>2m/s change) between the profile reading at the draft of the transducer and the Micro-X. All MBES lines were sound speed corrected using CARIS HIPS' "Nearest in Time" method. OSI submitted sound speed data in NetCDF format to the National Centers for Environmental Information (NCEI) on March 23, 2021 via the S2N tool. Survey junctions for Project OPR-B300-KR-20.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/OPR-B300-KR-20_Junction_Overview.jpgSurvey H13385 junctions with 2 contemporary surveys, and has no junctions with prior surveys. Figure 5 displays the location of the junction surveys for Project OPR-B300-KR-20. Junction analyses were conducted by generating a difference surface in CARIS HIPS for each pair of surveys to compare the MBES surfaces where they overlap. A histogram of the depth differences was plotted to show the relative agreement of the surveyed depths. The magnitude of differences were compared to the maximum allowable TVU, which was 0.5m for the water depths in Survey H13385.Surface-to-surface difference histogram comparing Surveys H13384 and H13385.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13384-vs-H13385.jpgThe western border of Survey H13385 junctions with the eastern border of Survey H13384. The area of overlap is approximately 5.2km long and 250m to 350m wide. A histogram of depth differences between the two surveys is shown in Figure 6. The two surveys are in good agreement, with less than 0.1% of nodes having depth differences greater than the maximum allowable TVU. The depth differences observed were primarily in rocky areas, including the northern shore and the areas near Execution Rocks. 2020WH133845000Ocean SurveysSurface-to-surface difference histogram comparing Surveys H13385 and H13386.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385-vs-H13386.jpgThe eastern border of Survey H13385 junctions with the western border of Survey H13386. The area of overlap is approximately 8.2km long and 250m to 300m wide. A histogram of depth differences between the two surveys is shown in Figure 7. The surveys are in good agreement, with less than 0.1% of nodes having depth differences greater than the maximum allowable TVU. The depth differences observed were primarily in rocky areas near the northern shoreline. 2020EH1338610000Ocean SurveysSurvey H13385 backscatter mosaic overlaid on a composite of RNCs.file:///B:/OPR-B300-KR-20/Surveys/H13385/01_HDR/Reports/DR/Report/H13385_DR/H13385-Backscatter-Mosaic.jpgAll equipment and survey methods were used as detailed in the DAPR.The survey data meets or exceeds requirements as set forth in the NOS Hydrographic Surveys Specifications and Deliverables (2020), Field Procedures Manual (2014), Letter Instructions, and all HSD Technical Directives. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required with the exception of deficiencies noted in the Descriptive Report.All field sheets, this Descriptive Report, and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch.As Chief of Party, field operations for this hydrographic survey were conducted under my direct supervision, with frequent personal checks of progress and adequacy. I have reviewed the attached survey data and reports.Chief of Party2021-05-27John R. BeanData Processing Manager2021-05-27David T. SomersMean Lower Low Waterbuffer_newVdatum2_Merge_Diss_100m_NAD83-MLLW_geoid12b.csarbuffer_newVdatum2_Merge_Diss_100m_NAD83-MHW_geoid12b.csarERS via VDATUMAdditional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Projected UTM 18NYCICentral IslipNYVHValhallaCTDADarienNYBRBrooklyn PierNJI2NJ Inst of Tech 2ZNY1New York WAAS 1NYLCLake CarmelNYRHRiverheadCTBRBrookfieldNJMTNJMTNJNTNeptune TownshipCTGUGuilfordOSNROcean Surveys New RochelleSmart BaseNorth American Datum 1983