OPR-K414-NRT4-13Galveston Bay and VicinityGalveston BayNavigation Response Team 4H123915Vertical control via discrete zoning.Southern Galveston BayTexasUnited States100002013Dan JacobsNavigable Area2013-06-282013-06-042013-10-28Multibeam Echo SoundermetersUniversal Transverse Mercator (UTM)UTCPacific Hydrographic BranchAlthough the survey was conducted in 2013, the official project number assigned to this survey is OPR-K414-NRT4-11. The purpose of this survey is to provide contemporary surveys to update National Ocean Service (NOS) nautical charts. All separates are filed with the hydrographic data. Any revisions to the Descriptive Report (DR) generated during office processing are shown in bold, red italic text. The processing branch maintains the DR as a field unit product, therefore, all information and recommendations within the body of the DR are considered preliminary unless otherwise noted. The final disposition of surveyed features is represented in the OCS nautical chart update products. All pertinent records for this survey, including the DR, are archived at the National Geophysical Data Center (NGDC) and can be retrieved via http://www.ngdc.noaa.gov/.NOAAH12391 is located from Bolivar Roads to red Fish Light 1 along the Houston Shipping Channel in Galveston, Texas. It comprises water depths around 4 meters and deeper. H12391 is bounded to the north by H12392 and to the south by H12388. 29.497438888994.869352777829.379302777894.8057388889H12391 Assigned and Surveyed Area Polygonsfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/SurveyBoundary.jpgField work for H12392 had not commenced at the time H12391 was completed.Survey Limits were acquired in accordance with the requirements in the Project Instructions and the HSSD.The regional Navigation Manager has received pilot and port authority requests for hydrographic surveys in Galveston Bay and vicinity. The main purpose is to survey the newly charted barge channels along the main Houston Ship Channel. MCD also requested NRT4 to investigate numerous charted features near the main Houston Ship channel , in an effort to reduce localized chart clutter. In addition, Galveston, Texas City and Houston are port cities on the MTS175 port list and require ENC verification investigation of features. It is the intent of this survey to supersede all bathymetry, seafloor features, and bottom characteristics within the assigned survey area as defined by these instructions for updating of NOAA charts 11324, 11326, 11327 and 11328. The N.A.L.L. line for this project is defined as the 4 meter depth contour.The entire survey is adequate to supersede previous data.Complete MBES coverage was obtained for the entire survey as specified by Hydrographic Survey Project Instructions OPR-K414-NRT4-12 dated 5/16/2013 and all other applicable direction. The intent of this survey is to supersede all bathymetry, sea floor features, and bottom characteristics within the survey boundaries. Complete MBES coverage was achieved in waters approximately 4 meters to 18 meters in depth except where the hydrographer deemed it unsafe. Complete coverage inside the southern AWOIS circle between marker 35A and WR35B was not obtained due to charted depths shoaler than 6ft. Please reference section D.1 AWOIS for more information.Coverage to the 4 meter curve was nearly but not completely attained in the sublocality of Red Fish Bar, H12391. The Hydrographer deemed ten (10) lines of MBES coverage to adequately address this section of seafloor which was predominantly composed of migrating sand waves. Sand wave depths were 4 meters, nominally. Missed coverage to 4 meter curve (inside yellow box), Chart 11327file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/4MeterCurveJustification.jpgH12391 0.5m CUBE Surfacefile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_Coverage.jpgS12110265.92000009.8800265.92000009.8803.86080001.872013-06-042013-06-052013-06-122013-06-132013-06-172013-06-202013-07-022013-07-032013-07-152013-07-192013-07-252013-08-202013-08-282013-08-292013-09-042013-09-182013-09-242013-09-252013-09-272013-10-212013-10-28Thirteen AWOIS items were assigned for the survey and nine were investigated.Refer 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.S1211100.5S1211file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/S1211.jpgSimrad3002MBESApplanixPOSMV4Positioning SystemOdomDigibar ProSound Speed SystemSeabirdSeacat SBE-19+Conductivity, Temperature, and Depth SensorPlease reference NRT4's 2013 DAPR.Multibeam Echosounder (MBES) crosslines totaled 9.4 nautical miles comprising 3.9% of main scheme acquisition. The prescribed 4.0% percent (2013 HSSD, 5.2.4.3) was not obtained on account of confounding dredging operations and deteriorating weather conditions. The data were binned at .01m for analysis. They were found to have an even distribution, and did not exhibit an offset from 0, which increased confidence in the data collection and processing parameters. The data, when using .56m as the cut off depth difference, were found to be 98% within specification. Extreme outliers of 6.6m and -2.7m only had a single instances.Percentage of Data Split at .56m Depth Differencefile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/SurfaceDifference/Step_3_ComputeStatistics_.01mbin.jpgDistribution of Data Histogram Binned at .01mfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/SurfaceDifference/Step_3_ComputeStatistics_.01mbin2.jpgThe data is adequate for charting despite not meeting the crossline requirements.S12110.500.3Uncertainty values of submitted, finalized grids were calculated in CARIS using the "Greater of the Two" of total propagated uncertainty and standard deviation (scaled to 95%). All project depths were less than 100 meters thus the IHO Order 1 Formula: ((0.5^2 + ((Depth *0.013)^2 )) ^0.5), was implemented for quality control analysis. Therefore survey depths of 4~18 meters had an acceptable uncertainty budget range of 0.500 meters to .564 meters. Dredging: As discussed in section B.2 Factors Affecting Soundings and D.2 Additional results, significant dredging operations occurred during this survey. Because half of the bathymetry data were collected before the dredging operations commenced, there are unusually high uncertainty values demonstrated along each of these newly excavated trenches, Figure 8. The green color represents values that are less than or equal to .56, red is indicative of values greater than .56. Therefore the majority of H12391 is compliant with the specified IHO standards. Tidal Error: Tidal error is not applicable for this project. Tidal Constituent And Residual Interpolator (TCARI) automatically calculates the error associated with water level interpolation. This error is incorporated into the residual/harmonic solutions and included in the Total Propagated Error (TPE) for the survey. Uncertainty values input into TCARI model are 2-sigma. Pydro will automatically supply 1-sigma values to CARIS when computing uncertainty. IHOness: An IHO Order 1 child layer called "IHOness" was created on the finalized 0.5 meter surface using the formula: ((0.25+((Depth*0.013)^2))^0.5)-Uncertainty. A color range of -3 to -0.001 (Red) and 0 to 3 (Green) showed areas in which IHO limits were exceeded, i.e. Red<0. Locations in red closely agree with a.) dredging operations or b.) where a difference of two weeks or more had elapsed in the acquisition of adjacent lines. See Figure 10.H12391 Dredging Scoursfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/Dredging%20Scours.jpgH12388 High Uncertainty Values due to Dredgingfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/Dredging_Uncertainty.jpgMBES Data Across a Newly Dredged Troughfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_DN270_Dredging.jpgIHOness Layer on finalized 0.5 meter CUBE Surfacefile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_IHOness.jpgHigher uncertainty values are expected in areas of steep topography, and in this case, the area of a recently dredged channel. The data is adequate for charting.H12388, Galveston Bay junctions to the South East of H12391 which is part of the same project, OPR-K414_NRT4-12.H12388100002013Navigation Response Team 4SEH12388, Galveston Bay junctions to the South East of H12391 which is part of the same project, OPR-K414_NRT4-12 (Figure 7). The overlapping region of each sheet's BASE surface were compared using the CARIS cursor information tool. 42 points were checked as shown in Figure 8. Of the 42, 38 points were within 2ft of each other and 4 points were within 4ft. Potentially, 90.5% of all data points in the overlapping region are within the 2ft range. 3 of the 4 points out of range were all measured on survey line 182629, DN183. See Figures 11 and 12.Junction of H12391 and H12388file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/Sheet%20Overlap2.jpgObservation Points Between Surveysfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/Sheet%20Overlap_DepthComparison.jpgThe differences noted in the junction comparison could be attributed to the dredging operations being conducted in and around the time of both surveys. Upon office examination, the differences noted are not navigationally significant and therefore the data is adequate for charting.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.Dredging ErrorsAs discussed in Section B.2 Uncertainty, dredging is a continual process throughout Galveston Bay. Unfortunately the survey team had not been made aware of the dredging schedule and nearly half of the survey days have lines affected by the changing bottom profile. This process increased the sediment percentage in the water column, mixed the thermal layering in the shipping channel, and created a great deal or turbidity that degraded our data quality on certain days.Possible Heave Artifact Induced by Deep Draft Vessel TrafficFigure 13 shows three survey lines that are not in agreement with each other, Day Number 171. Line number 1228 shown in pink has a 0.32m offset from two adjacent lines surveyed that day. The survey log states heavy traffic on the water that day and a large shipping container vessels went along side of S1211.0.32 Meter Offset, DN171file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_DN196_LN1228.jpgThe artifact shown from line number 1228 occurs on Day Number 196. The data with the heave artifact was rejected and the remaining data is adequate for charting.Density ErrorsWith complete MBES coverage gridded at 0.5 meters there is a density minimum requirement of 5 soundings for each .5m grid cell. The Density and IHO script was run on the finalized data set resulting in 99.64% pass rate with the average sounding density. The project instructions also stated that the density holidays must not exceed two interconnected grid cells. Upon inspection it was found that the two cell limit was exceeded in 4 separate areas. Two locations had 3 interconnected cells, and the other two locations had 5 interconnected cells.Object Detection Coverage pass Percentagefile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ObjectDetectionCoverage.jpg3 Node Density Holiday One, 29-28-30.8N 094-51-28.6Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_3Node_Density1.jpg3 Node Density Holiday Two, 29-26-09.8N 094-50-17.4Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_3Node_Density2.jpg3 Node Density Holiday One, 29-25-10.4N 094-49-48.4Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_5Node_Density1.jpg5 Node Density Holiday Two, 29-23-32.4N 094-48-55.7Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/H12391_5Node_Density2.jpgIn the areas where holidays are noted, there is no evidence of shoaling or significant features within the data gaps. The data is adequate for charting.Systematic Sonar Noise ErrorPeriodic "ringing" was evident in the multibeam data between depths of 10-15 meters. This artifact was evidenced by soundings stacking into a (positive) parabolic shape occurring at nadir and seemed to be unique trait of the EM 3002 echosounder system. The EM3002's Tx, Rx and pulse length settings are automated. A similar and possibly related phenomenon occurs in a (negative) parabolic shape of soundings at nadir and was typically observed over a smooth, sandy bottom.Noise Errorfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/Ringing.jpgThe data is adequate for charting despite the ringing artifacts.Sound Speed Cast Frequency: CTD casts were performed and the data loaded into the Kongserg EM 3002 (flat-faced) mulitibeam echo sounder using SIS acquisition software prior to logging data. Additional casts were made at four (4) hour intervals or more frequently when observed surface speed values changed significantly (3 meters per second or more). CTD casts were post processing using Caris Hips software.All equipment and survey methods were used as detailed in the DAPR.All data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.H12391 Raw Backscatter was logged but not processed.NOAA Extended Attribute Version 5.3.2NOAA Extended Attribute Version 5.3.2 was used in conjunction with CARIS BDB Version 4 for feature processing, management and creation of the Final Features File.H12391_05mCUBE0.5020NOAA_0.5mObject DetectionH12391_05m_FinalCUBE0.5020NOAA_0.5mObject DetectionPer Project Instructions OPR-K414-NRT4-13_PI_Change_1, dated 28 June 2013, coverage required for H12391 was "200% SSS with concurrent SBES or MBES, or Object Detection MBES". However, the original Project Instructions dated 16 May 2013 stated "200% SSS with concurrent SBES or MBES, or Complete MBES." This more exacting coverage requirement added extra survey days to the project. However, the field party continued with its original "MBES Only" acquisition scheme as it was integrating a new side scan sonar system.Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterTCARIGalveston Bay Entrance, North Jetty, TX8771341Galveston Pier 21, TX8771450Eagle Point, TX (TCOON)8771013Morgans Point, TX (TCOON)8770613Galveton Railroad Bridge, TX (TCOON)8771486K414NRT42013Final2013-11-112013-11-18COOPs provided time series data which were tabulated in metric units (meters), relative to MLLW and on Greenwich Mean Time on the 1983-2001 National Tidal Datum Epoch (NTDE).The following Water Level (.tid files) were used: 8770613.tid, 8771013.tid, 8771341.tid, and 8771450.tid.See attached tide note dated November 4, 2013North American Datum of 1983 (NAD83)UTM Zone 15 NorthAngleton, TX 301 kHz.H12391 surveyed soundings are generally deeper than the charted depths with a few instances being within 2ft. Charted depths circled in green indicate where H12391 soundings are within 2 feet of charted depths. Blue circled depths indicate where H12391's soundings are more than 2 feet deeper than charted. Charted depths circled in purple call out locations in which survey soundings displayed a change in depth greater than 10 feet. Survey depths shoaler than 2 ft from charted soundings do not exist. See figures, below.H12391 Chart (11327) Comparison, Section 1file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/G.jpgH12391 Chart (11327) Comparison, Section 2file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/F.jpgH12391 Chart (11327) Comparison, Section 3file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/E.jpgH12391 Chart (11327) Comparison, Section 4file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/D.jpgH12391 Chart (11324) Comparison, Section 5file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/C.jpgH12391 Chart (11324) Comparison, Section 6file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/B.jpgH12391 Chart (11324) Comparison, Section 7file:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ScreenCaptures/A.jpg11324125000382013-062013-06-222013-06-18Chart 11324 encompasses the Galveston Bay Entrance, the eastern half of Galveston, and the western end of the Bolivar Peninsula. It also includes the southern half of the Houston Ship Channel starting from Bolivar Roads. The controlling depths stated on the chart are discussed in section D.1 Channels. Heading towards Houston from Bolivar Roads the survey showed extensive deepening throughout the channel due to recent dredging. The chart shows a shoaled area with a depth of 6ft. This location has since been dredged out to approximate depths of 28ft as discussed in section D.1 Chart Comparison. 11327125000382013-062013-06-222013-06-18Chart 11327 encompasses the northern part of sheet H12391 and shows the end of the assigned Houston Ship Channel section at Red Fish Light 1. The chart itself covers upper and lower Galveston Bay and terminates at Atkinson Island. The survey of the northern half of the survey also showed extensive deepening throughout the channel due to recent dredging. Ten(10) AWOIS radii were assigned for Sheet H12391. Please reference the triple zero file (.000 file extension) entitled "H12391_FFF" accompanying this project in the folder called "S-57 Features" for attribution details. Eight (8) of ten (10) assigned AWOIS were esonified with 100% Object Detection, MBES coverage. Two (2) assigned AWOIS features (ID US0000002411_00001 and ID US0000002418_00001) were not addressed due to crew and equipment safety concerns, i.e. surf, deep draft vessel wakes in 6 foot depths. Please reference the Final Features File located in the folder "S-57_Features" of this project.Northern AWOIS Circlesfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/AWOIS_Circles_Figure1.jpgNorthern AWOIS Circles Chartfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/AWOIS_Circles_Table1.jpgSouthern AWOIS Circlesfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/AWOIS_Circles_Figure2.jpgSouthern AWOIS Circles Chartfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/AWOIS_Circles_Table2.jpgAWOIS Circles Not Addressedfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/AWOIS_Circles_NotAdressed.jpgThirteen AWOIS items were assigned for this survey. Nine required investigation and four were for information only. All the AWOIS items requiring investigation were addressed by the survey. See attached feature report.No Maritime Boundary Points were assigned for this survey.Please reference the Final Features File located in the folder "S-57_Features" of this project.Designated soundings not appearing in the Final Features File (FFF) were the shoalest depths over insignificant features which would have otherwise not been honored by the finalized CUBE surface. NRT4 located a feature within the main shipping channel on DN155 (Line 1042) and reconfirmed it on DN183 (Line 1182). The rectangular feature is approximately 4m Long, by 1.5m wide, by 1m tall. The USACE specified controlling depth for this area is 13.72m and the feature's shoalest point of 15.9m is 2.18m deeper than the required minimum. Therefore the feature was not listed as a DTON. USACE was notified of the object on 05DEC2013. USCG issued a Broadcast to Mariners and Local Notice to Mariners (LNM) on 12DEC2013. Official correspondence pertaining to this feature may be found in the folder named "Public_Relations_&_Constituent_Products." This object was classified (S-57) as an "obstruction" and can be found in the H12391's FFF.Uncharted Feature, 29-23-40.60N 094-48-53.28Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/ShippingCrate3.jpgSee attached correspondence regarding the uncharted, rectangular feature.No Danger to Navigation Reports were submitted for this survey.No shoals or potentially hazardous features exist for this survey.Houston Ship Channel: Depths within the channel have either stayed the same or increased in depth between 1-20ft. This is due to the extensive dredging efforts in the area. The area with the greatest change occurred in the barge lane on the eastern side of the Houston Shipping Channel at the southern end of the sheet. The general location of the point shown in the referenced figure below is 29:23:43.30 N and 94:48:47.98 W. The controlling depths for the channels at MLLW are: Left Outside Quarter: 41ft Left Inside Quarter: 45ft Right Inside Quarter: 43.6ft Right Outside Quarter: 41ft Barge Lane: 12ft The survey depths were found to exceed controlling depth requirements for all quarters as well as within both barge lanes.20ft Depth Change After Dredging Effortsfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/DeepeningArea_BargeLane.jpgThe controlling depths for Houston Ship Channel have since been updated and are depicted on the latest editions of the charts.No bottom samples were required for this survey.NRT4 completed a limited shoreline investigation.No prior survey comparisons exist for this survey.Aids to navigation (ATONs) exist for this survey, but were not assigned or investigated.No overhead features exist for this survey.No submarine features exist for this survey. No pipelines or cables were detected in crossing areas, Charts 11324 and 11327.No ferry routes or terminals exist for this survey.The submerged platform ruins in figure 34 were located within the charted bounding box. Figure 35 shows a feature on the edge of the charted box. The shape could be the submerged platform. If so the bounding box could be adjusted to the SE.Submerged Platform Ruins, 29-23-26.59N 094-48-39.89Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/SubmergedPlatformRuins_LatLon.jpgSubmerged Platform, 29-29-43.98N 094-51-49.64Wfile:///M:/OPRK414NRT413/Surveys/H12391/Report/Original/Report/ScreenGrabs_for_DR/SubmergedPlatform_LatLon.jpgShifting sandwaves exist at the northern end of H12391 in the sublocality of Red Fish Bar. See Section A.4 of this report.As mentioned in section B.2 Uncertainty, extensive dredging was occurring during, and has continued beyond, acquisition.The controlling depth (12 feet) of the barge lanes are not listed on the published charts. The charts for Galveston Bay and Houston Ship Channel have a Controlling Depths chart for the main shipping channels but the barge lanes are not mentioned. It is uncertain if there is an officially controlling depth for the Galveston Bay and Houston area. To inform commerce traffic of the lanes 12ft depth, it is suggested that a note be added within the controlling depth chart. Currently the only locations where the lane depth is listed are: 1. Navigating the Houston Ship Channel Brochure (Updated 2006) http://www.uscg.mil/vtshouston/docs/Houston_Ship_Channel_Brochure.pdf 2. Also found in another version here (Updated 2011): http://www.galvestonpilots.com/HOGANSACNavigatingtheHoustonShipChannel.pdf 3. Mariners Guide (only in a graphic. No text) http://www.houston-pilots.com/documents/pdf/mariners_guide91117b.pdfNo 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, 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.Dan JacobsNRT4 Team Lead (Acting)2013-12-16