OPR-B300-KR-20Long Island SoundNew York and ConnecticutOcean SurveysH133841Execution Rocks to East RiverNew YorkUnited States50002020John R. BeanNavigable Area2020-06-262020-08-232021-03-10Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUTCAtlantic Hydrographic BranchAny 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.ContractorThis survey provides hydrographic data for the waters of western Long Island Sound and the eastern East River. The general locations of the survey limits are presented in Table 1.40.90997573.91081440.75876773.707861Survey limits were acquired in accordance with the requirements in the Project Instructions and the HSSD.The 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.The 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)A small coverage gap exists at the Floating Pool, a public swimming pool at Barretto Point Park that is located on a permanently moored barge. The barge is within survey limits and not present on the chart; the survey vessel was not able to collect data in this area. Survey H13384 coverage overlaid on a composite of RNCsfile:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-Survey-Coverage.jpgRV Able 20856.20000038.50RV Osprey0446.90000026.50RV Ready 20513.20000014.1001816.30000079.104.361100016.42020-08-232020-08-242020-08-252020-08-272020-08-282020-08-312020-09-022020-09-032020-09-042020-09-082020-09-092020-09-102020-09-112020-09-132020-09-142020-09-152020-09-162020-09-172020-09-202020-09-212020-09-222020-09-232020-09-242020-09-252020-09-262020-09-272020-09-282020-09-292020-10-022020-10-032020-10-042020-10-052020-10-062020-10-092020-10-112020-10-132020-10-142020-10-152020-10-162020-10-172020-10-182020-10-192020-10-202020-10-212020-11-022020-11-032020-12-042020-12-072020-12-082020-12-092020-12-102020-12-112021-03-10Refer 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 27.60.4RV Osprey7.90.6RV Ready 27.60.4Teledyne RESONSeaBat T50-RMBESApplanixPOS MV 320 v5Positioning and Attitude SystemVelodyne LiDARVLP-16Lidar SystemTrimbleNetR9Positioning SystemAML OceanographicMicroX SVSound Speed SystemAML OceanographicBaseXSound Speed SystemAML OceanographicBaseX2Sound Speed SystemAll equipment was installed, calibrated, and operated in accordance with the DAPR. Multibeam crosslines acquired for this survey total 4.4% of mainscheme acquisition. Crosslines were collected on an ongoing basis throughout the survey as the vessels progressed through 6 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 1-2 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 depth difference occurred in the East River at the western end of the survey over some apparent sand waves, and in the northeast end of the survey near rocks and features. 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/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-XL-overview.jpgA frequency distribution of the depth differences between H13384 crossline vs mainscheme MBES data. Statistics from the depth difference sample set are displayed above the graph.file:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-mainscheme-vs-XL.jpgERS via VDATUM00.0945RV Able 241RV Osprey41RV Ready 241The 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 H13384 passed the uncertainty check, with 99.5+% of the nodes meeting uncertainty standards (Figure 4). H13384 MBES surface uncertainty statisticsfile:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384_MB_50cm_Finalized.QAv6.tvu_qc.pngNo prior surveys and one contemporary survey junction with Survey H13384. The contemporary junction with Survey H13385 is discussed in the DR for that survey.H13385100002020Ocean Surveys, Inc.EThe contemporary junction with Survey H13385 is discussed in the DR for that survey.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.None ExistThere were no other factors that affected corrections to soundings.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. This 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 5).H13384 MBES surface data density statisticsfile:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384_MB_50cm_Finalized.QAv6.density.pngAll data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.All equipment and survey methods were used as detailed in the DAPR.Survey H13385 backscatter mosaic overlaid on a composite of RNCsfile:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-Backscatter-Mosaic.jpgNOAA Profile Version 2020H13384_MB_50cm_MLLW_Final.csarCARIS Raster Surface (CUBE)0.5-0.97535.437NOAA_0.5mComplete MBESH13384_MB_50cm_MLLW.csarCARIS Raster Surface (CUBE)0.5-0.97535.437NOAA_0.5mComplete MBESH13384_MBAB_2m_400kHz_1of1MB Backscatter Mosaic2N/AProcessed BackscatterAdditional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterERS via VDATUMbuffer_newVdatum2_Merge_Diss_100m_NAD83-MLLW_geoid12b.csarbuffer_newVdatum2_Merge_Diss_100m_NAD83-MHW_geoid12b.csarNorth American Datum 1983Projected UTM 18Smart BaseCentral IslipNYCIValhallaNYVHDarienCTDABrooklyn PierNYBRNJ Inst of Tech 2NJI2New York WAAS 1ZNY1Lake CarmelNYLCRiverheadNYRHBrookfieldCTBRNJMTNJMTNeptune TownshipNJNTGuilfordCTGUOcean Surveys New RochelleOSNRThe user-installed station OSNR was used on all survey days except October 2, 2020 (DN 276). On this day, the base station antenna was temporarily disconnected and repositioned by an electrician at the host building. After the repositioning, no further interruptions in service occurred. See the HVCR for details. 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. US5NY12M10000312020-05-282020-05-28US5NY15M20000402021-02-042021-02-04US5NY16M20000352021-02-042021-02-04US5NY1DE1000012020-05-282020-11-09US5NY1DG1000012021-02-092021-02-09US5NYCFH1000012020-05-282020-11-09US5NYCFJ1000012021-02-092021-02-09There were 89 DTONs accepted for Survey H13384, 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 submerged obstructions. Additionally, the ENC rescheming process resulted in some older soundings being removed from the new charts, so previously-charted hazards were reported as DTONS based on the published ENCs. 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. There were 3374 features assigned in Survey H13384. Underwater rocks were the most common, with 905 assigned; most of the addressed rocks were adequately represented by the bathymetry grid and not recommended for retention on the chart as individual features. Wrecks and obstructions accounted for 439 assigned features, 122 of which were area features. Per the HSSD, any wreck with a length greater than 1mm at survey scale was to be replaced with an area feature; however, OSI was granted an exception to this and area features were created for wrecks with a length greater than 2mm at survey scale, or 10m in length. Wrecks under this cutoff were represented by a point feature. See the correspondence in Appendix II for details. There were 839 new features surveyed in H13384, as well as 257 features that required updates or changes in position from the chart. Most of these features were wrecks; there were 495 new or improperly charted wrecks surveyed. New wrecks and obstructions with any dimension greater than 2mm at survey scale were added as area features, per OSI's waiver to modify the HSSD requirement that features greater than 1mm at survey scale be made into areas (see the correspondence in Appendix II). Significant uncharted baring or exposed rocks were surveyed with lidar and included as new features, categorized as rocks or land areas based on their surveyed height. Uncharted docks and piers were added when sufficient lidar data was collected to position them. See the FFF for details. Uncharted features of particular note that were surveyed and positioned with a combination of multibeam and lidar data include a new building in Flushing Bay (Figure 7) and the Barretto Point Park floating swimming pool (Figure 8).Lidar data, shoreline video, and an MBES/lidar surface overlaid on aerial imagery showing the position of a new building.file:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-new-building.jpgLidar data, shoreline video, and an MBES/lidar surface overlaid on aerial imagery showing the Barretto Point Park floating pool. Pool photo from NYCgovparks.org.file:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-Barretto-Pool.jpg There are 4 charted channels in the survey coverage of H13384: East River Channel, South Brother Island Channel, Flushing Bay and Creek Channel, and New Rochelle Harbor Channel. Additionally, survey data covered 3 dredged area features without channel names that were assigned in the CSF. Rikers Island Channel appears as a named water area but has no dredged area or maintained depth information so is not included in this discussion. For the East River Channel, survey data covers part of Reach G and all of Reach H and Reach I. Controlling depths for these reaches are 27.5 ft, 24.8 ft, and 34.9 ft, respectively. The project depth is 35 ft. No survey data indicated areas shoaler than the controlling depth for the reach, and only a few places were shoaler than the project depth. Most of these were charted features or on the border of the channel. No uncharted depths in the channel were greater than 20cm above project depth. South Brother Island Channel consists of a channel and a turning basin, both of which are entirely within the surveyed area and have project depths of 35 ft. Controlling depths in the channel range from 27 to 28.4 ft, and in the turning basin from 32.1 ft to 35.3 ft. No surveyed depths were shoaler than the controlling depths listed for the area. The turning basin is deeper, with just a few spots at 34 or 35 ft and the rest below project depth. The channel has broad shoaling through most of its length, deepening as it nears the turning basin. Flushing Bay and Creek Channel has survey coverage over the entirety of the Main Channel, part of the Creek Channel, and a branch channel and maneuvering area. Project depth for all areas is 15 feet, and most of the middle half of the channels is at or near project depth. The channel outside quarters and maneuvering area range in depths from 4.5 ft to 11.8 ft, but all areas are below their controlling depths. The New Rochelle Harbor Channel has survey coverage for approximately 450m north from the seaward end. The charted depth for the channel is 5.9 ft, and all but the edges were at or below that depth. The eastern slope of the channel was surveyed at 5.6ft in one area, and the western slope at the northern edge of the survey coverage shoals to 4.5 ft. An irregularly-shaped dredge area feature south of South Brother Island Channel was disproved by survey data. The charted depth is 25ft, reported in 1999, and surveyed data showed depths ranging from 11ft to 31ft, in keeping with nearby soundings and contours with nothing indicating a defined dredged area. The other 2 charted dredged areas assigned connect Eastchester Bay to the Hutchinson River Channel and were found to be below their charted depth values. There were 180 ATONs assigned in Survey H13384. Most were found on station and operating as intended, and are included in the FFF. Field observations documented 9 ATONS that were not present and 20 that were off station by more than 2mm at survey scale. There was also 1 damaged structure and 1 mis-numbered buoy. All of these discrepancies were reported to the US Coast Guard and the reports are included in Appendix II. There was 1 uncharted ATON observed that was not documented in the FFF as it was deemed temporary. A mooring structure charted alongside a pier was found collapsed and submerged, and a small buoy marked the dangerous area on the surface.No Maritime Boundary Points were assigned for this survey.The 11 assigned bottom samples for Survey H13384 are documented in the FFF.There are 14 bridges and 1 overhead cable charted in Survey H13384. The cable was verified visually in the field. Of the bridges, 1 was observed to have a discrepancy between its charted and observed position. A short bridge connecting a building to land in Flushing Bay was observed farther north than charted, and the building was also substantially different than charted. Vessel mounted lidar data matches the aerial imagery from NYGIS 2020. A comparison of the aerial imagery to the charted bridge is shown in Figure 8. Another bridge, the City Island Causeway, is attributed as being under construction. The field crew did not observe any signs of construction activity, and a government press release states that construction was completed in 2017. There were 5 bridges located beyond the NALL and not visible from the survey area, and all other bridges were verified to exist as charted. NYGIS 2020 aerial imagery compared to the charted position of a building and bridgefile:///B:/OPR-B300-KR-20/Surveys/H13384/01_HDR/Reports/DR/Report/H13384_DR/H13384-bridge-position.jpgA number of exposed cable or pipeline segments were surveyed in a charted cable and pipeline area in the East River, north of North Brother Island. These cables and pipelines are not individually charted and many appear bent, broken, and disjointed. None were observed to be suspended above the seafloor or otherwise hazardous. These features are documented in the non-DTON Pipe Report and the FFF, along with other non-DTON pipe segments observed throughout the survey. There were also 2 pipes surveyed that were submitted as DTONS. The Iroquois Gas Transmission System pipeline is present as charted and runs approximately 18km along the length of the survey, from the Bronx River eastward and past the survey boundary. A trench is visible in the bathymetry for most of the pipeline's length, but at no point did the pipeline itself appear exposed. There were 2 platforms assigned for this survey, a point and an area feature. Both were described as ruined and were located near one another on the west side of North Brother Island. No platforms were found within the limits of bathymetry. Several ruined structures are present in this area but none were identifiable as platforms. No charted ferry routes or terminals exist for this survey. On 4 occasions during field operations, the field crew observed a ferry but its route and terminal were not investigated. No abnormal seafloor or environmental conditions exist for this survey.No construction or dredging was observed within the survey limits.No new surveys or further investigations are recommended for this area.The re-schemed ENC tiles published so far within this survey are at a scale of 10,000. There are 4 new ENCs that are in progress for this survey area, 2 of which are at a scale of 10,000 and 2 at a scale of 20,000. 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. 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 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.John R. BeanChief of Party2021-05-27David T. SomersData Processing Manager2021-05-27