OPR-B370-TJ-13Eastern Long Island SoundLong Island SoundNOAA Ship THOMAS JEFFERSONH124821Jacobs Pt to Mattituck InletNew YorkUnited States200002013CDR Lawrence T. KreppNavigable Area2013-02-132013-03-302013-04-20Multibeam Echo SoundermetersUniversal Transverse Mercator (UTM)UTCAtlantic Hydrographic BranchNOAAThis survey covers an area of approximately 24 SNM in Long Island Sound in the vicinity of Jacobs Pt to Mattituck Inlet.41.106572.64741.021333333372.55451H12482 Survey Area within OPR-B340-TJ-13file:///I:/H12482/Data/Descriptive_Report/Report/images/H12482_Survey_Area.jpgThis project is being conducted in support of NOAA's Office of Coast Survey to provide contemporary hydrographic data in order to update the nautical charting products and reduce the survey backlog within the area. In addition, data from this project will support the Long Island Sound Seafloor Mapping Initiative in New York and Connecticut. This project will cover approximately 61 square nautical miles of which 48 square nautical miles are critical survey areas as designated in the NOAA Hydrographic Survey Priorities, 2012 edition.The entire survey is adequate to supersede previous data.Survey Limits were acquired in accordance with the requirements in the Project Instructions and the HSSD.2H12482 Coverage Areafile:///I:/H12482/Data/Descriptive_Report/Report/images/H12482_Coverage_Area.jpgSurvey H12482 contains 17 holidays within the survey extents. They are the result of improper sonar tuning, poor vessel steerage, or failure to meet the edge of the defined sheet limit.2013-03-302013-03-312013-04-012013-04-022013-04-032013-04-042013-04-052013-04-062013-04-072013-04-082013-04-092013-04-162013-04-172013-04-182013-04-20810002431020272.40000018.50S-2220783.50000035.5001055.90000053.905.1Refer 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.S-22220815HSL 3102315.2S-222 and HSL 3102 acquired multibeam, sound velocity, attitude data, and bottom samples.SeabirdSBE 19+Conductivity, Temperature, and Depth SensorBrooke OceanMVP 100Sound Speed SystemApplanixPOS/MVPositioning and Attitude SystemReson7125 SV1MBESReson7125 ROVMBESResonSVP71Sound Speed SystemApplied Micro SystemsSmart SV&TSound Speed SystemTrimbleSPS351Positioning SystemVessel configurations, equipment operations, and data acquisition and processing were consistent with specifications described in the DAPR.The Thomas Jefferson and HSL 3102 collected 53.9 linear nautical miles of MBES crosslines, equating to 5.1% of mainscheme data. Crosslines were filtered to 45 degrees on either side of nadir and compared to mainscheme using a difference surface, created in CARIS BathyData BASE. Using the difference surface, every instance of overlap was evaluated. For the 2m grid, 838,701 nodes of 838,761 were within 1.0 meter. The differnece in depth ranged from -1.96 meters to 1.03 meters. The mean was 0.0 meters, and the standard deviation was 0.06 meters. For the 50cm grid, 4,022,179 nodes of 4,022,306 were within 1.0 meter. The difference in depth ranged from -5.98 meters to 6.74 meters. The mean was 0.0 meters, and the standard deviation was 0.06 meters. Survey H12482 complies with section 5.2.4.3 of the HSSD (2013 ed.)0.000.000.1020.00S-22210.2310240.2The method used to calculate Total Propagated Uncertainty values for survey H12482 varied based on the process used to apply water level values to the data. The first method was applied to data reduced to MLLW using a POSPac IAAPK 3D positional solution and a VDatum separation mode. For this data, realtime uncertainty values for roll, pitch, gyro, navigation, and elevation were supplied via a SBET RMS file generated by Applanix POSPac. The remaining sources of uncertainty were a combination of: field assigned values for sound speed uncertainties; Operations Branch assigned values for VDatum separation model uncertainty; and a priori values for sonar mounting and vessel speed based on Appendix 4, table 4.9 of the NOAA Field Procedure Manual (ed 2013). Field assigned values for sound speed are in Table 7 above, Operations Branch assigned values for the VDatum model are in row 2 of Table 6. The second method used to calculate Total Propagated Uncertainty was applied to data reduced to MLLW via TCARI tides. This data again used a POSPac IAAPK 3D positional solution, but used a TCARI grid to reduce the data to MLLW. Uncertainties for this data also used an SBET RMS file for realtime roll, pitch, gyro, navigation, and elevation uncertainties, as well as a priori values for sonar mounting and vessel speed. However, uncertainties associated with water level measurements and interpolation were automatically calculated as part of the TCARI water levels, and applied to the data during the Merge process. Since TCARI automatically calculates the error associated with water levels, no field assigned values were given in the Tide Uncertainty (see row 1 of Table 6). Field assigned values for sound speed uncertainties remained the same as data reduced via VDatum (see table 7). Total Propagated Uncertainties for the entirety of the survey were evaluated to ensure compliance with section 5.1.3 of NOAA's HSSD (ed 2013). First the maximum allowable uncertainty for each node was calculated using the equation: -Uncertainty/((0.5^2 +((Depth*0.013)^2))^0.5). Second the ratio between the actual uncertainty and maximum allowed uncertainty was found for each node. The resulting 'IHO_Order1' layer was filtered using a colour map to show any areas where the ratio exceeded -1.0, indicating the surface failed to meet IHO Order 1 standards. The hydrographer noted that uncertainty increased in three distinct instances on the survey. The first increase was over the crest of sandwaves, particularly in the Northeast section of the 2m grid. The uncertainty over these sandwaves stems from two sources, a timing error detailed in section B.2.9 of this report , and a vertical offset described in section B.2.5 of this report. Despite the offsets, a majority of the sandwave area meets IHO order 1 vertical uncertainty. The exceptions to IHO Order 1 occur along the steep slopes of the larger sandwaves. The second increase in Uncertainty was seen as alongtrack striping on overlapping outerbeams between parallel survey lines. The striping occurs on Julian Days 090 and 091 for platform S222, particularly when those lines have low overlap in the outerbeams. The source of the error could be the result of the vertical offset previously mentioned, poor sound velocity resolution, or the timing error described in section B.2.9 of this report. At no point does the striping exceeded IHO order 1 specifications. The third increase in Uncertainty occurred on Julian Days 095 and 096, on which poor sonar tuning created noisy data. The noise does not cause fliers in the CUBE surface, but can be seen as stippling in the IHO_Order 1 layer.3H12482 Uncertainty : Sandwaves slopes show as red exceptions to IHO Order 1. file:///I:/H12482/Data/Descriptive_Report/Report/images/IHO%20Order%201%20-%20Sandwaves.jpgSix contemporary junction surveys exist with H12482. Two difference surfaces, one for 50cm grid resolution and another for 2m resolution, were created in Caris BaseEditor to evaluate general agreement between H21482 and each respective junction survey.4H12482 Junction Surveysfile:///I:/H12482/Data/Descriptive_Report/Report/images/H12482_Junctions.jpgH10930100001999NOAA Ship RUDESWA comparison with H10930 was not conducted because the .xyz file provided could not be properly converted to a .csar file.H12480200002012NOAA Ship THOMAS JEFFERSONNWThe difference between the current survey and survey H12480 ranged from -0.22 meters to 0.342 meters. The mean was -0.03 meters. The standard deviation was 0.054 meters. Out of 43,716 nodes at the junction 100% were within 1.0 meter.H11255100002004NOAA Ship THOMAS JEFFERSONWThe difference between the current survey and survey H11255 ranged from -0.158 meters to 0.813 meters. The mean was 0.344 meters. The standard deviation was 0.097 meters. Out of 90,440 nodes at the junction 100% were within 1.0 meter.H11360100002004NOAA Ship THOMAS JEFFERSONSWThe difference between the current survey and survey H11360 ranged from -0.468 meters to 1.238 meters. The mean was -0.115 meters. The standard deviation was 0.107 meters. Out of 30,452 nodes at the junction 99.9% were within 1.0 meter.H11999100002008NOAA Ship THOMAS JEFFERSONNThe difference between the current survey and survey H11999 ranged from -2.245 meters to 3.027. The mean was 0.163 meters. The standard deviation was 0.42 meters. Out of 62,342 nodes at the junction 95.5% were within 1.0 meter. The junction covers a sandwave area, and the difference likely stems from movement of the sandwaves.H12483200002013NOAA Ship THOMAS JEFFERSONEAt the time the junction between H12482 and H12483 was analyzed, H12483 had only been preliminarily processed by the field unit. For the 2m grid, 197,665 nodes of 202,228 (97.7%) were within 1 meter. The difference in depths ranged from -3.748 meters to 3.264 meters. The mean was -0.019 meters. The standard deviation was 0.347 meters. For the 50cm grid, 1,683,343 nodes out of 1,690,818 (99.5%) were within 1 meter. The difference in depths ranged from -8.007 meters to 6.258 meters. The field unit believes the large depth range is a result of fliers in the uncleaned surface of H12483. The mean was -0.096 meters. The standard deviation was 0.154 meters.Sonar system quality control checks were conducted as detailed in the quality control section of the DAPR.High Current on Julian Day 090On Julian Day 090 the Thomas Jefferson ran tracklines perpendicular to the prevailing current. As a result, the ship experienced a settlement and squat artifact that was not resolved by the dynamic draft table input in the the vessel's CARIS HVF file. The vertical offset can be seen in the base surface, but does not exceed IHO Order 1 specifications, with the exception of the Northeast corner. This area is dominated by sandwaves, the crests of which accentuate the artifact and exceed IHO Order 1 specifications.5Vertical Offset induced by high current environment.file:///I:/H12482/Data/Descriptive_Report/Report/images/Vertical%20offset%20induced%20by%20current.jpgNone ExistThere were no other factors that affected corrections to soundings.Sound speed casts were taken every 30 minutes to 1 hour from S-222 using the ship's Moving Vessel Profiler. On 3102, casts were taken at least twice per day using the Seabird Seacat 19+ CTD.All equipment and survey methods were used as detailed in the DAPR.Changes to HVF for S-222During post-processing, a variable timing error was noted for S-222 data on Julian Days 089 and 090. The timing error induced a horizontal offset visible in the sand waves on the Northeast section of the sheet. Due to the variable nature of the timing offsets, the error was reduced but not eliminated by entering corrections into the vessel’s HVF file. The remaining horizontal error is still visible in the sand wave area when viewed in Caris Subset Editor, but remains within Horizontal Uncertainty specifications listed in Section 3.1.1 of the HSSD (ed. 2013).Density RequirementsThe density of all surfaces was calculated using the compute statistics function in CARIS Base Editor. It was found that greater than 95% of nodes contain 5 or more soundings.All data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Raw Backscatter was logged as a 7k file and has been sent to the Processing Branch. One line per vessel, per day was processed aboard the Thomas Jefferson in order to assess and ensure quality. No processing or visualization errors were noted.NOAA ProfileField Version 5.3.2H12482_CUBE_CombFinal_2m_FinalCUBE21.5735.00NOAA_2mComplete MBESH12482_Cube_2m_MLLW_FinalCUBE218.0035.00NOAA_2mComplete MBESH12482_CUBE_50cm_MLLW_FinalCUBE0.51.5720.00NOAA_0.5mObject DetectionThis survey was processed using the Combined Uncertainty and Bathymetry Estimator (CUBE) algorithm. Per section 5.2.2.1 of NOAA HSSD Manual (2013 ed), all MBES were gridded according to depth: 0.5m resolution for depths ranging from 0-20m, and 2m for depths 19m and greater. ERS SurfacesThe survey deliverables do not include surfaces with data reduced to the ellipsoid.True Heave ErrorLine 011_2205, collected by S-222 on DN 091 does not have True Heave applied to it because of an error in CARIS HIPS/SIPS.Vertical control for this survey was done with a combination of TCARI and VDATUM ERS methods, as discussed below.Mean Lower Low WaterTCARINew Haven, CT8465705New London, CT8461490Mattituck Inlet, NY8512668B370TJ2013_FinalFinal2013-04-222013-06-07All data have TCARI tides calculated using verified water levels and final TCARI griding. Preliminary zoning did not include the Mattituck Inlet gauge installed by the field unit due to issues with the tidal data reducing to MLLW. Final zoning includes this gauge.VDatum2013_B370_VDatum_Ellip_MLLWA majority of survey H12482 was post processed to the ellipsoid using a POSPac 3D IAPPK positional solution, and then reduced to MLLW using an VDatum separation model supplied by HSD’s Operations Branch. Per Appendix I of the Hydrographic Survey Project Instructions, the field unit analyzed the accuracy of the separation model via parallel processing of crosslines. Based on the analysis, the field unit submitted a request to use VDatum as a final vertical datum reducer, which the Operations Branch approved. For a full description of the validation request and approval, refer to Appendix I of this report. To review the crossline analysis, refer to Separates II of this report. During post processing, the hydrographer noted an occasional vertical offset induced by applying the separation model. The field unit was unable to discover the nature of the error, and reverted some data to TCARI water levels. Additional lines could not be reduced via VDatum due to improper logging of POSPac files. For a complete list of lines reduced to MLLW via TCARI, refer to the document H12482_reduced_via_TCARI.xls, located in Appendix II of this report.North American Datum of 1983 (NAD83)18 NSmart BaseNJTWMount Laurel, NJCTNENewington, CTMOR5East Moriches, NYZNY1New York WAAS 1, NYNYRHRiverhead, NYCTGRGroton, CTCTGUGuilford, CTCTMAMansfield, CTCTDADarien, CTNYCICentral Islip, NyThe real-time GPS navigation data were overwritten by post-processed SBET data using Smart Base.Moriches, NY (238 kHz)A chart comparison was conducted with a survey sounding set overlayed with the largest scale raster chart. The comparison with the ENC was conducted using a difference surface of the combined grids and an interpolated TIN of the ENC soundings.12358140000212011-072011-06-282011-07-09Charted and surveyed soundings generally agree within three feet. Exceptions occur in the sand wave area of the northeastern section of the sheet and in the central part of the sheet, where the 100 foot contour has shifted westward and surveyed soundings are 10-15 feet deeper than charted. The 12-ft and 18-ft contours were surveyed to be inshore of those currently charted.6H12482 - Contoursfile:///I:/H12482/Data/Descriptive_Report/Report/images/H12482_Contour_Shift.jpgUS5NY1IM4000052013-02-152013-02-15falseCharted soundings and those surveyed generally agree within 2 meters. Exceptions occur in the northeastern section of the sheet, which is a sand wave area, and in the central part of the sheet, where there is an area west of the charted 100 foot contour that was surveyed to be approximately five meters deeper than currently charted. There is shifting of the 12 foot and 18 foot contours, similar to that present on the raster chart.A total of three AWOIS items fell within the bounds of survey H12482. Two were located inshore of the NALL and were not addressed. The search radius for the third AWOIS item also extended inshore of the NALL, and was not fully developed. For a full description, see the Final Feature File.No Maritime Boundary Points were assigned for this survey. See Final Feature File. See Final Feature File.1Danger to Navigation Reports are included in Appendix II of this report. See Final Feature File.The charted soundings within the designated anchorage area in the western section of this sheet generally agree with the surveyed soundings within two feet. Of 22 assigned bottom samples, only 8 were collected. See Final Feature File for details.The shoreline investigation requirements stated in the Project Instructions include verification of features inshore of the NALL. These features were not developed by the field unit because it was deemed unsafe.Prior survey comparisons exist for this survey, but were not investigated.Aids to navigation (ATONs) exist for this survey, but were not investigated.No overhead features exist for this survey.The most northwestern extent of this survey touches a cable area. No visible cables were seen in the submitted grids; any cables are assumed to be properly buried.No ferry routes or terminals exist for this survey.No platforms exist for this survey.See Final Feature File.No present or planned construction or dredging exist within the survey limits.No new surveys or further investigations are recommended for this area.No new insets are recommended for this area.As Chief of Party, Field operations for this hydrographic survey were conducted under my direct supervision, with frequent personal checks of progress and adequacy. I have reviewed the attached survey data and reports.All field sheets, this Descriptive Report, and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch.The survey data meets or exceeds requirements as set forth in the NOS Hydrographic Surveys and Specifications Deliverables Manual, Field Procedures Manual, Standing and Letter Instructions, and all HSD Technical Directives. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required with the exception of deficiencies noted in the Descriptive Report.Lieutenant Commander Christiaan Van WestendorpActing Commanding Officer2013-09-12Lieutenant Megan R. GuberskiOperations Officer2013-09-12Lieutenant Junior Grade Lindsey L. NormanSheet Manager2013-09-12