Coastal Single-beam Bathymetry Data Collected in 2025 From Milton Pass, Florida

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   Bemelmans, Christopher C., DeWitt, Nancy T., and Brown, Jenna A., 20260424, Coastal Single-beam Bathymetry Data Collected in 2025 From Milton Pass, Florida:.

   This is part of the following larger work.
   Bemelmans, Christopher C., DeWitt, Nancy T., and Brown, Jenna A., 20260424, Coastal Single-Beam Bathymetry Data: Midnight Pass and Milton Pass, Florida, June 2025: U.S. Geological Survey data release doi:10.5066/P13I93P7, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P13I93P7

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -82.3561454
   East_Bounding_Coordinate: -82.3473990
   North_Bounding_Coordinate: 26.9109874
   South_Bounding_Coordinate: 26.9030733
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Calendar_Date: 26-Jun-2025

   Currentness_Reference:

   ground condition

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: tabular, vector, and raster digital data
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point (333,109)
   2. What coordinate system is used to represent geographic features?
      

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:

      UTM_Zone_Number: 17N
      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -81.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000
      

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in meters
      The horizontal datum used is World Geodetic System of 1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257223563.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Datum_Name: World Geodetic System of 1984
      Altitude_Resolution: 0.01
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method: Attribute values
      

7. How does the data set describe geographic features?

   Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt

   Comma-delimited ASCII text file (.txt) containing the processed single-beam bathymetry data points from USGS FAN 2025-313-FA (subFANs 25BIM03 and 25BIM04). Data is projected to the processing datum WGS84 (G2296) UTM Zone 17N. (Source: U.S. Geological Survey)

   X_EASTING_WGS84(G2296)

   x-axis coordinate, easting, WGS84 (G2296) UTM 17N. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	365336.43
   Maximum:	366195.89
   Units:	meters

   Y_NORTHING_WGS84(G2296)

   y-axis coordinate, northing, WGS84 (G2296) UTM 17N. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2976420.95
   Maximum:	2977288.56
   Units:	meters

   ELLIPSOID_WGS84(G2296)

   z-value, ellipsoid height (elevation), WGS84(G2296) UTM17N. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	-32.46
   Maximum:	-25.47
   Units:	meters

   YEAR

   Day of year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2025
   Maximum:	2025

   DOY

   Day of year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	177
   Maximum:	177

   DATE

   Day of year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	6/26/2025
   Maximum:	6/26/2025

   UTC_TIME

   Universe Coordinate Time (UTC) of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	13:31:24.142
   Maximum:	16:41:35.877
   Units:	HH:MM:SS.sss

   HYPACK_Line

   Identifier assigned to each HYPACK® line during acquisition. (Source: HYPACK®/U.S. Geological Survey) Line name example 25BIM03_WVR1_0011_1732, where the first 7 characters are the subFAN followed by underscore (25BIM03_), the next 4 characters are the platform/vessel separated by an underscore (WVR1_), and the last 9 characters are the HYPACK® line number and start time (HHMM) in UTC separated by an underscore (0011_1732). If the same line name had multiple segments a 4-digit number was appended after the line number (for example, _0001).

   Milton_Pass_2025_SBES_NAD83_NAVD88_GEOID18_UTM17N_xyz.txt

   Comma-delimited ASCII text file (.txt) containing the processed single-beam bathymetry data points from USGS FAN 2025-313-FA (subFANs 25BIM03 and 25BIM04). Data were transformed from its processed datum to NAD83 NAVD88 UTM Zone 17N coordinate system with respect to the GEOID 18 datum. (Source: VDatum)

   X_EASTING_NAD83(2011)

   x-axis coordinate, easting, NAD83 (2011) UTM 17N. (Source: VDatum)

   Range of values
   Minimum:	365337.105
   Maximum:	366196.565
   Units:	meters

   Y_NORTHING_NAD83(2011)

   y-axis coordinate, northing, NAD83 (2011) UTM 17N. (Source: VDatum)

   Range of values
   Minimum:	2976420.363
   Maximum:	2977287.973
   Units:	meters

   ORTHOMETRIC_NAVD88_GEOID18

   z-value, orthometric height adjusted (elevation) in NAVD88 GEOID 18. (Source: VDatum)

   Range of values
   Minimum:	-7.069
   Maximum:	-0.082
   Units:	meters

   YEAR

   Year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	2025
   Maximum:	2025

   DOY

   Day of year of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	177
   Maximum:	177

   Date

   Calendar date of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	6/26/2025
   Maximum:	6/26/2025

   UTC_TIME

   Universe Coordinate Time (UTC) of data acquisition. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	13:31:24.142
   Maximum:	16:41:35.877
   Units:	HH:MM:SS.sss

   HYPACK_LINE

   Identifier assigned to each HYPACK® line during acquisition. (Source: HYPACK®/U.S. Geological Survey) Line name example 25BIM03_WVR1_0011_1732, where the first 7 characters are the subFAN followed by underscore (25BIM03_), the next 4 characters are the platform/vessel separated by an underscore (WVR1_), and the last 9 characters are the HYPACK® line number and start time (HHMM) in UTC separated by an underscore (0011_1732). If the same line name had multiple segments a 4-digit number was appended after the line number (for example, _0001).

   Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_tracklines.shp

   Polyline shapefile of the single-beam bathymetry tracklines (135 tracklines in total). (Source: Esri)

   FID

   Automatically generated feature attribute by Esri. (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0
   Maximum:	134

   Shape*

   Automatically generated feature attribute by Esri. (Source: Esri) Polyline ZM

   Shape_Length

   Length of the trackline polyline, in meters. (Source: Esri)

   Range of values
   Minimum:	67.27
   Maximum:	819.83
   Units:	meters

   HYPACK_Lin

   Identifier assigned to each HYPACK® line during acquisition. (Source: HYPACK®/U.S. Geological Survey) Line name example 25BIM03_WVR1_0011_1732, where the first 7 characters are the subFAN followed by underscore (25BIM03_), the next 4 characters are the platform/vessel separated by an underscore (WVR1_), and the last 9 characters are the HYPACK® line number and start time (HHMM) in UTC separated by an underscore (0011_1732). If the same line name had multiple segments a 4-digit number was appended after the line number (for example, _0001).

   Entity_and_Attribute_Overview:

   Milton_Pass_2025_SBES_1m_DEM_WGS84_G2296_UTM17N.tif: A 1-m cell size gridded DEM GeoTIFF (.tif) created from the x,y,z point dataset in this data release (Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt). The ellipsoid elevation ranges from -25.49 to -32.46 m and is projected in WGS84 (G2296) UTM 17N. The file format is 32-bit floating point GeoTIFF with 860 columns, 868 rows.

   Entity_and_Attribute_Detail_Citation:

   The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Christopher C. Bemelmans
   • Nancy T. DeWitt
   • Jenna A. Brown
2. Who also contributed to the data set?
   Funding and (or) support for this study was provided as part of the coastal assessment component of the Consolidated Appropriations Act Title VII, Division N: Disaster Relief Supplemental Appropriations Act, 2023 (Public Law 117-328). The authors would like to thank members of the USGS SPCMSC Operations staff, specifically Kyle W. Kelso and Benjamin A. Galbraith for their bathymetry acquisition field support as well as Emily L. Johnson for additional field and land support. This document was improved by scientific/editorial and metadata reviews from Billy J. Reynolds and Breanna N. Williams of the SPCMSC.
3. To whom should users address questions about the data?
   Nancy T. DeWitt

   U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 2025 (process 1 of 7)

   GNSS Acquisition: As reported on the FPRN FLSS CORS station datasheet, the base station was equipped with a Leica Geosystems® GR50 GNSS receiver using a Leiar20 SCIT antenna recording at a rate of 1.0 seconds (s) equal to 1 hertz (Hz). The roving vessels were each equipped with a Spectra Precision® SP90M GNSS receiver using Spectra Precision® SPGA Rover GNSS antennae recording full-carrier-phase positioning signals from satellites at a rate of 0.1 s, or 10 Hz. Post-survey, the base station data files were downloaded from the FDOT FPRN online server location in the non-proprietary Receiver Independent Exchange Format (RINEX [https://igs.org/wg/Rinex/]) format version 3.04 (e.g. FLSC17700.250). The proprietary Spectra Precision® G-files (e.g. GWVR1A24.177) from the rovers were converted into RINEX format version 3.04 (e.g. WVR100000_R_20251772001_02H_10Z_MO) which converts all the satellite constellations tracked by the antenna (GPS, GLONASS, Bideau, and Galileo). Example of the RINEX 3.04 filename is FLSC177l00.25O, where the convention FLSC is the four-letter site name, 177 is the day of year, I is the session A-Z, 00 is the time, 25 is the year, O represents the observation file, N is the navigation file, M is meteorological file, and G is the GLONASS navigation message file. Example of the RINEX 3.04 filename WVR100000_R_20251762001_02H_10Z_MO where the convention WVR100000 is the nine-letter site name, R is the data source (R - receiver), 20251772001 is the year (2025), day of year (177), and Coordinated Universal Time (UTC) start time of the file in HHMM (2001), 02H is the file time (2 hours), and the 10Z is the recording rate (10 Hz), MO is the mixed observation file, MN is the mixed navigation file, and MM is meteorological file. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources used in this process:

   • Spectra Precision® proprietary G-Files

   Data sources produced in this process:

   • RINEX version 3.04 format files

   Date: 2025 (process 2 of 7)

   Single-Beam Bathymetry Acquisition: A total of 37.50 line-km of SBES data were collected as part of FAN 2025-313-FA: the R/V Shark (WVR1 - subFAN 25BIM03) collected 21.13 line-km, and R/V Chum (WVR2 - subFAN 245BIM04) collected 16.37 line-km of data. Boat motion (heave, roll, pitch) was recorded on each vessel at 50-millisecond (ms) intervals using a SBG Systems® Ellipse Series A motion sensor. HYPACK®, a marine surveying, positioning, and navigation software package, managed the planned-transect information and provided real-time navigation parameters, course corrections, data quality parameters, and instrumentation-status to the boat operator. Depth soundings were recorded at 50-ms intervals using an Teledyne® Odom Echotrac CV100 echosounder with a 4-degree, 200-kilohertz (kHz) transducer on WVR1 and WVR2. For each vessel, data from the GNSS receiver, motion sensor, and echosounder were recorded in real-time and merged into a single raw data file (.RAW) in HYPACK®, with each device string referenced by a device identification code and time stamped to UTC. Sound velocity profile (SVP) measurements were collected using SonTek Castaway® Conductivity, Temperature, and Depth (CTD) instruments. The CTD units were cast overboard to record changes in water column speed of sound (SOS) spatially and temporally. A total of 6 casts recorded sound velocities ranging from 1547.90 to 1548.88 meters per second (m/s) at water depths ranging from a minimum of -0.15 m to a maximum of -6.62 m. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources produced in this process:

   • *.RAW, *.BIN, *.LOG,*.ctdx, *.ctd, *.csv, *.svp

   Date: 2025 (process 3 of 7)

   Differentially Corrected Navigation Processing: All navigation data were acquired in WGS84 (G2296)/International Terrestrial Reference Frame of 2020 (ITRF2020). The FLSS coordinates used for post-processing the navigation collected during this survey were 26° 59' 24.69514" North, 82° 22' 22.61898" West, -19.679 m ellipsoid height, and epoch 2025.0073 obtained from the FPRN FLSS datasheet (https://www.myfloridagps.com/ds/pdfs/flss.pdf). The rover data, base data, and the base station coordinates were imported into GrafNav (NovAtel, 2023). Each kinematic GNSS data session from the survey vessel was post-processed to the concurrent static base GNSS data session. GNSS data plots and data information generated by GrafNav including satellite health (satellite lock, satellite cycle slips), rover trajectory maps, and pre-processing logs were used to modify the processing parameters to attain trajectory solutions (between the base and the rover) that resulted in fixed positions. Primary examples include: 1) excluding satellites, flagged by GrafNav, with bad health or frequent cycle slips, 2) omitting satellite time segments that introduce positional errors which prevented a fixed solution, or 3) adjusting the satellite elevation mask angle to improve the position solutions (NovAtel, 2023). The final differentially corrected, precise DGPS positions were computed at 0.1s and exported as a single data point epochs in ASCII text format (.txt) in WGS84 (G2296) UTM Zone 17N geodetic datum. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources used in this process:

   • RINEX version 3.04 format files

   Data sources produced in this process:

   • *.txt

   Date: 2025 (process 4 of 7)

   Single-beam Bathymetry Processing: All data were processed using HYPACK® 2023 following steps outlined in the HYPACK® 2023 User Manual (Xylem, 2023). First, the HYPACK® project geodesy settings were verified, ensuring the correct UTM Zone and "K-N from User" settings with "height of ellipsoid above chart datum" value of '0.00' were selected. Next, the .RAW data files were imported into HYPACK® Single Beam Editor (64 bit). The following "Read Parameters" were selected: within the Survey Tab 'Elevation Mode' and the project information was verified. Within the Corrections Tab: the sound velocity profiles (SVP) were added as .VEL format and 'Time and Position' was selected for the SVP interpolation method. Within the Devices Tab: the vessel offsets were added and the RTK Tides box was selected. Within the Processing Tab: 'Apply Heave Correction', 'Correct Induced Heave', 'Remove Heave Drift', 'Avoid Double Heave', 'Merge Tide Data with Heave', 'Interpolate Draft', 'Apply Pitch and Roll Corrections', and 'Steer Sounding Beam' (4 degree for the TVEE, WVR1, and WVR2) were all selected. The data was then processed within HYPACK®'s Single Beam Editor (64 bit). Next, the GPS Adjustment tool was used to merge the post-processed navigation trajectory epoch solutions with their respective HYPACK® data files (.RAW). Using the Editor Profile window, these processed soundings were visually scanned for any resultant outliers which were manually removed using the editor tool. The data were then smoothed using the smoothing option with the 'number of samples for average" set to 60. Finally, the x,y,z data (easting, northing, ellipsoid height) and associated attributes (calendar date, UTC time, and line number) were exported as a single text file per line. The text files were them combined into one file per subFAN/vessel using the Esri ArcGIS Pro "Merge (Data Management)" geoprocessing tool, resulting in two main text files. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources used in this process:

   • *.RAW, *.BIN, *.LOG, *.VEL

   Data sources produced in this process:

   • 25BIM03_WVR1_PP_Merge.txt
   • 25BIM04_WVR2_PP_Merge.txt

   Date: 2025 (process 5 of 7)

   Quality Control, Quality Assurance (QA/QC) and Uncertainty Analysis: Using ArcGIS Pro, the processed single-beam datasets were then transformed into feature classes using the "Create Points From Table > XY Table to Point" geoprocessing tool and the spatial reference was set to WGS84 UTM 17N. Next, a polyline feature class (representing tracklines) was produced from the point data using XTools Pro "Make Polylines from Points" (the selection criteria being HYPACK® line name and then ordering by UTC time). Utilizing both the point and polyline feature classes, an ArcGIS Pro Python script was used to evaluate the elevation differences at the intersections of tracklines. The script does this by calculating the elevation difference between points at each intersection using an inverse distance weighting equation with a search radius of 1 m. The crossing analysis yielded a Root Mean Square Error (RMSE) of 5.80 cm for all crossings. When the WVR1 crossed one of its own lines, the crossing analysis yielded an RMSE of 4.80 centimeters (cm). When the WVR2 crossed one of its own lines, the crossing analysis yielded an RMSE of 6.80 cm. The crossings in ArcGIS Pro were solely used as a QA/QC, not as a means of editing the data. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources used in this process:

   • 25BIM03_WVR1_PP_Merge.txt
   • 25BIM04_WVR2_PP_Merge.txt

   Data sources produced in this process:

   • Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt
   • Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_Tracklines.shp

   Date: 2025 (process 6 of 7)

   Datum Transformation: NOAA NGS's VDatum software was used to transform the single-beam data points' horizontal (x,y) and vertical (z) datums from WGS84 (G2296) UTM 17N (horizontal), WGS84 (G2296) ellipsoid height (vertical) using epoch year 2025.482 (start of the survey) to NAD83 UTM 17N (horizontal), NAVD88 orthometric height (vertical) using GEOID18 epoch year 2010.000. The VDatum-reported vertical uncertainty is 0.033 m. For more information about the positional accuracy for these datum transformations, visit the Estimation of Vertical Uncertainties VDatum webpage, https://vdatum.noaa.gov/docs/est_uncertainties.html. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources used in this process:

   • Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt

   Data sources produced in this process:

   • Milton_Pass_2025_SBES_NAD83_NAVD88_GEOID18_UTM17N_xyz.txt

   Date: 2025 (process 7 of 7)

   Digital Elevation Model (DEM) Creation: Using ArcGIS Pro version 3.2.3 and the single-beam point data file (Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt), a 1 x 1-m cell resolution DEM was generated using ArcGIS geoprocessing tools. First, a polygon feature class was created using "Create Feature Class (Data Management)" tool and was shaped to the single-beam data file extent using ArcGIS Pro "Edit Vertices" tool. This polygon feature class was then converted to a 1 X 1-m cell size raster using the "Feature to Raster (Conversion)" tool. Second, using the single-beam point data file (Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt), a 1-m DEM was generated using the "Natural Neighbors (Spatial Analyst)" tool. Third, the DEM was clipped to the 1-m raster (created in the first step) using the "Extract by Mask (Spatial Analyst)" tool. The computation results produced minimum and maximum ellipsoid height values of -25.49 to -32.46, which closely resemble the single beam point data values of -25.47 to -32.46. Last, to quantify how closely the 1-m DEM represents the single-beam point data, the "Extract Values to Points (Spatial Analyst)" tool was used. This tool extracts the value from the DEM at each single-beam data point location. The 1-m DEM represented 332,216 of 333,109 with 893 (0.27%) reported as null values. Using the generated feature class and associated attribute table, the RMSE was calculated as 0.021 m. The DEM was then exported as a Geographic Tag Image File Format (GeoTIFF, .tif) file with the symbology set to stretch. Person who carried out this activity:
   

   Nancy T. DeWitt

   U.S. Geological Survey

   Geologist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   ndewitt@usgs.gov

   Data sources used in this process:

   • Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt

   Data sources produced in this process:

   • Milton _Pass_2025_SBES_1m_DEM_WGS84_G2296_UTM17N.tif

3. What similar or related data should the user be aware of?
   NovAtel, 202307, Waypoint Software 9.00 User Manual v11: Novatel Inc., Alberta, Canada.

   Online Links:

   • https://hexagondownloads.blob.core.windows.net/public/Novatel/assets/Documents/Manuals/Waypoint-Software-User-Manual-OM-20000166/Waypoint_9.00_Software_User_Manual.pdf

   Xylem, 2023, HYPACK® 2023 User Manual: A Xylem brand, Middletown, CT.

   Online Links:

   • https://www.xylem.com/siteassets/brand/hypack/resources/manual/2023-hypack-user-manual.pdf

   Stark, Nina, Gardner, Michael, Grilliot, Michael, Lyda, Andrew, Dedinsky, Karen, Mueller, Jaquelin, Pezoldt, Charli, Hubler, Johnathan, Castro-Bolinaga, Celso, Schueller, Alexander, Zhan, Weiwei, Haefeli, Michael, Burghardt, Sarah, Wondolowski, Maxwell, Holberg, Sam, Hassan, Mohamed, Parker, Jack, Laurel-Castillo, Jorge, Eggensberger, Lea, Nichols, Elliot, Herndon, Hanna, Wang, Ping, Lizaso, Maitane Olabarrieta, Raubenheimer, Brit, Hashash, Youssef, Adusei, Stephen, and Jafari, Navid, 20250130, NEER/GEER: Hurricanes Helene & Milton Dataset: Multidisciplinary Pre, During and Post Storm Data Collection doi:10.17603/ds2-m8h3-5802, U.S. National Science Foundation Natural Hazards Engineering Research Infrastructure (NSF NHERI), DesignSafe-CI.

   Online Links:

   • https://doi.org/10.17603/ds2-m8h3-5802

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?
   This dataset is derived from a single survey using two vessels with identical equipment systems and acquisition settings. Prior to deployment, each vessel's equipment offsets were surveyed using a Geotronics/Spectra Precision Geodimeter® 640 total station equipped with an electronic theodolite and an electronic distance meter. Offsets between the single-beam transducers, motion reference unit, and the antenna reference point (ARP) were precisely measured with respect to the vessels frame of reference. During mobilization, the offset measurements were field checked and verified against the total station measurements. Total station offsets were then digitally entered into the acquisition and (or) processing software. Methods were employed to maintain data collection consistency aboard the vessels. Differential Global Positioning System (DGPS) base station coordinates were obtained from the Florida Department of Transportation (FDOT) Florida Permanent Reference Network (FPRN) datasheets for the Continuously Operating Reference Stations (CORS) used to process the navigation data. Roving vessels remained within < 10-km of the CORS base station. The navigation positioning data were post processed using NovAtel®'s Waypoint Software GrafNav.
2. How accurate are the geographic locations?
   The FDOT FPRN CORS station Sarasota South, code name FLSS (NGS PID DR9091), was used for the local control, and the coordinate values were obtained from FPRN's FLSS datasheet (https://www.myfloridagps.com/sc/flss.pdf). The maximum horizontal surface vector distance from the base station to both roving vessels was 9.87 km. Horizontal positional accuracy associated with each data point was determined by post-processed differential correction of the base/rover GNSS sessions using GrafNav. Processing the full-carrier phase data allows precise positioning of the base and rover receivers. Differential processing improves the rover positions by assessing positional errors computed at the base receiver and applying those errors or differences to the rover receiver. Forward and backward time-series processing of the kinematic (rover) data provides an independent combined smoothed-trajectory solution of the baseline between the rover position and the base station. The positional accuracy can be estimated by differencing the time series (position separation). The average post-processed horizontal standard deviation accuracy (2-sigma) for all kinematic rover data processed to FLSS CORS station was 0.013 +/- 0.001 meters (m).
3. How accurate are the heights or depths?
   The FDOT FPRN CORS station Sarasota South, code name FLSS (NGS PID DR9091), was used for the local control, and the coordinate values were obtained from FPRN's FLSS datasheet. The vertical position accuracy associated with each data point was determined by post-processed differential correction of the base/rover GNSS sessions using GrafNav. The average post-processed vertical standard deviation accuracy (2-sigma) for all kinematic rover data processed to the FLSS CORS station was 0.002 +/- 0.005 m.
4. Where are the gaps in the data? What is missing?
   This data release contains single-beam bathymetry data points (x,y,z) collected in June 2025 within and around Milton Pass, Florida. The horizontal positions and vertical elevations are provided in two datums, 1) WGS84 (G2296) and ellipsoid height, and 2) NAD83(2011) NAVD88 UTM 17N GEOID18. These datasets are considered complete. Users are advised to read the complete metadata record carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   These data were collected during one survey with consistent instrument calibrations and consistent acquisition methods.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

   Attn: USGS SPCMSC Data Management

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8000 (voice)

   gs-g-spcmsc_data_inquiries@usgs.gov
2. What's the catalog number I need to order this data set? Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.txt, Milton_Pass_2025_SBES_NAD83_NAVD88_GEOID18_UTM17N_xyz.txt, Milton_Pass_2025_SBES_1m_DEM_WGS84_G2296_UTM17N.tif, Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_tracklines.shp
3. What legal disclaimers am I supposed to read?
   Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:

     comma-delimited text, shapefile

     Network links:

     https://coastal.er.usgs.gov/data-release/doi-P13I93P7/data/Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P13I93P7/data/Milton_Pass_2025_SBES_NAD83_NAVD88_GEOID18_UTM17N_xyz.zip https://coastal.er.usgs.gov/data-release/doi-P13I93P7/data/Milton_Pass_2025_SBES_WGS84_G2296_UTM17N_tracklines.zip https://coastal.er.usgs.gov/data-release/doi-P13I93P7/data/Milton_Pass_2025_SBES_1m_DEM_WGS84_G2296_UTM17N.zip

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 24-Apr-2026

Metadata author:

U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

Attn: USGS SPCMSC Data Management

600 4th Street South

Saint Petersburg, FL

United States

727-502-8000 (voice)

gs-g-spcmsc_data_inquiries@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)