H11123 HCell Approval DigSig

NOAA FORM 76-35A

U.S. DEPARTMENT OF COMMERCENATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

NATIONAL OCEAN SERVICE

DESCRIPTIVE REPORT

Type of Survey HYDROGRAPHIC

Field No. Sheet S

Registry No. H11123

LOCALITY

State Alaska

General Locality Sitka

Sublocality Silver Bay

2004

CHIEF OF PARTY PS David A. Sinson, NOAA

LIBRARY & ARCHIVES

DATE

NOAA FORM 77-28 U.S. DEPARTMENT OF COMMERCE REGISTER NO.(11-72) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

HYDROGRAPHIC TITLE SHEETH11123

NSTRUCTIONS The hydrographic sheet should be accompanied by this form, FIELD NO.

filled in as completely as possible, when the sheet is forwarded to the office. Sheet S

State Alaska

General Locality Sitka

Sublocality Silver Bay

Scale 1:10,000 Dates of Survey 10/24/2004 - 10/28/2004

Instructions Date 9/23/2004 Project No. OPR-O112-TC-04

Vessel R.V. Davidson

Chief of Party David A. Sinson, NOAA

Surveyed by SAIC Personnel

Soundings taken by echo sounders: Reson Seabat 8101, Reson SeaBat 8125, Reson Seabat 8111

Graphic record scaled by SAIC Personnel

Graphic record checked by P. Holmberg

Evaluation by K. Brown Automated plot by N/A

Verification by K. Brown, P. Holmberg

Soundings in Fathoms and Feet at MLLW

REMARKS: Time in UTC. UTM Projection Zone 8

Revisions and annotations appearing as endnotes were

generated during office processing.

All separates are filed with the hydrographic data.

As a result, page numbering may be interrupted or non-sequential

NOAA FORM 77-28 SUPERSEDES FORM C&GS-537 U.S. GOVERNMENT PRINTING OFFICE: 1986 - 652-007/41215

1

Descriptive Report to Accompany Hydrographic Survey H11123

Project OPR-O112-TC-04 Silver Bay

Sitka, Alaska Scale 1:10,000 October 2004

NOAA Time Charter R/V DAVIDSON Lead Hydrographer: PS David A. Sinson, NOAA Survey Manager: PS Peter S. Holmberg, NOAA

A. AREA SURVEYED This hydrographic survey was completed as specified by Hydrographic Survey Letter Instructions OPR-O112-TC-04, dated September 23, 2004, and the Draft Standing Project Instructions dated March 23, 2004. The survey area includes Silver Bay, Alaska.1

Northern Limit Southern Limit Western Limit Eastern Limit 57-03-37.01 N 56-57-40.93 W 135-13-55.37 N2 135-06-29.26 W

Data acquisition was conducted from October 24 to October 28, 2004 (Julian day numbers 298 to 302).

Figure 1 OPR-O112-TC-04 Survey O112S limits and coverage

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B. DATA ACQUISTION AND PROCESSING Refer to OPR-O112-TC-04 Data Acquisition and Processing Report (DAPR)3 for a complete description of data acquisition and processing systems, survey vessels, quality control procedures and data processing methods, submitted under a separate cover. Additional information to supplement sounding and survey data, and any deviations from the DAPR are included in this descriptive report. B1. Equipment and Vessels Data were acquired by the R/V DAVIDSON, survey launches R2 and D2 and a skiff (DP). The ship was used to acquire mid-water multibeam soundings (MWMB) in depths generally greater than 40 meters, sound velocity profiles and bottom samples. Launch D2 acquired shallow-water multibeam sounding in depths generally less than 120 meters, sound velocity profiles and bottom samples. Launch R2 acquired high-resolution shallow water multibeam soundings in depths generally less than 60 meters, sound velocity profiles and bottom samples. The skiff acquired vertical-beam soundings for shoreline buffers and high-precision geographic positions for shoreline feature verification. Vessel configurations, equipment operation and data acquisition and processing were consistent with specifications described in the DAPR. B2. Quality Control B2.1 System Certification and Calibration Refer to OPR-O112-TC-04 Data Acquisition and Processing Report (DAPR) for a description of system integration and initial calibration results for equipment and sensors utilized for this survey. B2.2 Crosslines The linear miles of crossline data is less than the requirement for NOAA standard specifications. The long and narrow configuration of Silver Bay, the short time frame of the survey, and the steep nature of the shoreface were not conducive to effective crossline data quality analysis. Multibeam echosounder crosslines totaled 2.88 nautical miles, comprising 2.52% of SWMB hydrography. Crossline soundings were evaluated with respect to main scheme soundings in Caris HIPS subset area editor and gridded base surface models. In general, there was good agreement of soundings for crosslines to maincheme lines, overlapping lines, day-to-day and vessel-to-vessel comparisons. Refer to Section B2.4.4 for a description of systematic error observations.

B2.3 Junctions No contemporary surveys junction with H11123.4 B2.4 Data Quality Factors B2.4.1 Sound Velocity Profiles ISS2000 applies sound velocity correction in real-time during echosounder acquisition. Sound velocity profiles were collected often to characterize the variable and complex water column conditions in the survey area. Surface sound velocity was monitored continuously on R2 with the Reson 8125 HRSWMB and on the DAVIDSON with the Reson 8111ER to ensure correct

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beam formation. Surface sound velocity was used by the 8125 system for correct beam formation on the flat-faced transducer for directional accuracy, and on the 8111ER for correct beam formation for pitch stabilization. Changes in surface sound velocity were also evaluated as an indicator of changes in the water column sound velocity. In general, there was good agreement of depths between overlapping outer beams of survey lines. There is no indication of significant sound velocity errors in the final base surface. B2.4.2 Water level correction ISS2000 applies predicted water-level correctors with CO-OPS supplied zoning in real-time during echosounder acquisition. Verified tides from the primary tide gauge are applied to soundings prior to NOAA quality review in Caris HIPS/SIPS. Soundings from crosslines and overlapping lines were examined using 3-D sounding subsets and base surfaces to identify temporal variation of water level modeling. In general, there was no indication of significant water level correction errors visible in line-to-line comparisons or the final base surfaces. B2.4.3 Residual Sounding Fliers and Noise Caris BASE surfaces were evaluated to focus data editing on areas of high standard deviation of depth. Full-density sounding subsets were reviewed where high standard deviation was indicated. Residual gross flyers and noise were identified in areas of unusually high standard deviation and flagged as rejected. The total range of standard deviation was reduced to a value that corresponded to general bathymetric relief for the survey area. Soundings from multiple lines were evaluated when possible to distinguish noise from bathymetric features. B2.4.4 Systematic Errors Caris BASE surfaces were evaluated to identify systematic errors in data correctors including motion, attitude, tide and sound velocity. Sunlight illuminated surface digital terrain models (DTM) did not indicate errors in heave, pitch and roll correction. Standard deviation surface models were evaluated to find areas where disagreement occurred between multiple lines – an indication of temporal variation in water-level or sound velocity correction. Two lines (R2mba04300_d16, and R2mba04300_d01) had an offset of 1meter between them, possibly caused by horizontal position error. Steep vertical bluffs may have contributed to DGPS multipath or signal blockage which degraded position accuracy and caused vertical offset of depths along a gradual sloping bottom (Figure 2). From Figure 2, a horizontal offset of 5 meters (within specifications)5 would produce greater than 5 meters of vertical offset. The short time frame of this offset observation is also more indicative of a GPS outage as opposed to a long-term tide correction error.

Figure 2

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B2.4.5 Sounding Coverage Daily coverage was evaluated with DTM models created from preliminary, gridded sounding data. SAIC submitted 2-meter shoal-biased binned data for launches and 5-meter shoal-biased binned data for the ship. Easting, northing, and depth data were imported into MapInfo and re-gridded in Vertical Mapper. DTMs were subsequently evaluated for coverage and delineation of the 8-meter inshore limit. Final sounding coverage was evaluated in Caris using BASE surface DTM, TPE and sounding density models. B2.4.6 Swath Angle Filtering All soundings were filtered to within 55 degrees of nadir for mutibeam echosounder bathymetry to increase confidence in sounding accuracy and minimize sound velocity errors. In some cases, outer-beam soundings were re-accepted for holidays and general bathymetry in deeper water to fill in small gaps in the final BASE surface. B2.4.7 Total Propagated Error (TPE) Raw soundings were not filtered for TPE. BASE surfaces were created from soundings filtered for TPE values that met IHO Order 1 tolerance. TPE filtering increased the confidence of sounding accuracy based upon system parameter settings in the Caris HIPS Vessel File (.hvf). Caris configuration files were created from manufacturer system performance specifications and offsets provided by SAIC from the System Acceptance Test (SAT). Caris configuration files for the launches and ship were submitted to HSTP and PHB for review and validation. TPE was viewed in Caris surface models to evaluate sounding accuracy and confidence for significant features and final coverage. Total propagated error for the survey ranged from 0.247 – 0.796 meters. All soundings are qualified by an associated TPE confidence value. B3. Water Level Datum Reduction HDCS sounding data were reduced to mean lower-low water (MLLW) using verified tides from the primary station at Sitka (945-1600), adjusted for zoned range and amplitude correctors provided by CO-Ops as specified in the project instructions and illustrated in Figure 3.

Figure 3 OPR-O112-TC-04 Survey O112S Tide Zoning Limits

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These data and correctors were also used to reduce soundings and heights of detached positions (DPs) to MLLW when acquired relative to a local water-level datum. All other datum reduction procedures conform to those outlined in the DAPR. C. VERTICAL AND HORIZONTAL CONTROL C1.1 Horizontal Control The horizontal datum for this project is the North American Datum of 1983 (NAD83). Differential GPS (DGPS) was the sole method of positioning. Differential corrections from U.S. Coast Guard beacons at Gustavus, AK (288 kHz) and Annette Island, AK (323 kHz) were utilized during this survey. DGPS Confidence checks were performed daily by comparing positions acquired by primary (POS/MV) and secondary (Trimble MS 750) positioning systems on the ship and launches. Confidence checks were performed on the skiff by comparing Ceeducer DGPS positions with Trimble DGPS positions.6 C1.2 Vertical Control The vertical datum for this project is Mean Lower-Low Water (MLLW). The operating National Water Level Observation Network (NWLON) primary tide station at Sitka, AK (945-1600) will serve as control for datum determination and as the primary source for water level reducers for survey H11123. The Pacific Hydrographic Branch will apply final approved (verified) tides to the survey data during final processing.7 A request for delivery of final approved (verified) tides for this survey was forwarded to N/OPS1 on December 31, 2004 in accordance with the FPM and project letter instructions. D. RESULTS AND RECOMMENDATIONS D.1 Automated Wreck and Obstruction Information System (AWOIS) Investigations A total of twenty-one (21) AWOIS items were located within the limits of H11123 and investigated during this survey. Investigation methods, results, and charting recommendations have been entered into Pydro and are submitted with the digital data. Printouts of the AWOIS Database forms are included in Appendix VI of this report.8 D.2 Chart Comparison9 Survey H11123 was compared with chart 17326 (13th Ed.; August 2000, 1:40,000). Chart comparisons were performed in MapInfo using xyz (E,N,d) sounding data exported from the final base surface. Xyz data from the base surface were exported at 5-meter resolution from the finalized base surface. A MapBasic utility was used to evaluate base surface soundings within an appropriate search radius of the charted depth or feature. Chart comparison recommendations and comments are recorded as an attribute of a digital MapInfo radius table and compiled to a final chart comparison workspace and plot. Chart 17326 With the exception of a few steep ledges most of the depths from chart 17326 generally agree with the current survey. Differences of 1 - 7 fathoms or less occur along the edges of the bay.10 Silver Bay has particularly steep edges. An example of this is the trench west of Arguello Island (figure 4). The chart depicts the depths at the bottom of this trench, but actual soundings on the chart span the entire width of

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the narrow channel, creating a false sense of security that the channel is actually as wide as the charted soundings.11

Figure 4. Trench north-west of Arguello Island

Sawmill Cove at the north end of the bay is very different than charted. The Sawmill is now abandoned, and much of the shoreline construction has either been removed or fallen apart. The floating log booms have been removed, but many dolphins remain. The remaining dolphins do not match the node points of the log boom currently charted.12 Below the surface, the bottom is foul with logs and remnants of old fallen structures. The greatest depth discrepancies ranging from 3 to 6 fathoms occur along the east side of the cove paralleling the jetty. The cause of this discrepancy is not known, although the bottom is fowl logs and debris it is not enough to constitute that great of a difference. Herring Cove is no longer used for log storage and all of the charted dolphins have been disproved visually on the surface and by 100% high resolution multibeam (Reson 8125).13 The bottom of Herring Cove is littered with logs that sank while the area was used for log storage (figure 5).14 One submerged piling remains in the northwest corner of Herring Cove. The submerged piling was submitted as DTON no. 1.6 in section D4.1.15

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Figure 5. Multibeam backscatter image of sunken logs in Herring Cove

Final sounding comparisons, selection and designations will be made after the application of verified tides.16 D.3 Shoreline D3.1 Shoreline Source Data Shoreline source data for this survey was compiled by the Remote Sensing Division (RSD) from photogrammetric survey AK-9703B. Photogrammetry for this project was collected in 1997 and 1998. Digital vector shoreline was provided on the project CD as individual cartographic feature files (CFF) in MapInfo format (.tab) files. Shoreline was delivered in two files: one with linear MHW and MLLW shoreline and one with point/line obstruction and rock features. The geographic datum for all source shoreline is NAD83.

Survey AK-9703B (NAD 83), 1997-98 CFF Scale GC-10517 1:20,000 RSD supplied shoreline digital manuscript objects were separated into S-57 feature classes through an evaluation of CFF attributes. Additional features were digitized from electronic raster BSB charts and were used for reference purposes and chart evaluation. The following electronic raster BSB was used for reference purposes for this survey: Chart Number ENC ID Edition Scale 17326 17 13th; August 2000 1:40,000

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D3.2 Method of Shoreline Verification Few low-water shoreline windows were available during daylight hours for this survey; therefore, some shoreline features were not observed during shoreline verification. Also, the lack of tide windows prevented proper verification of the MHW and MLLW lines as depicted in the source shoreline files, CFF and charted. Verification focused primarily on shoreline features, not the shoreline shape. Submerged shoreline features were surveyed at higher levels of tide with launch multibeam echosounders, skiff single beam echosounder and visual examinations. Shoreline verification was conducted near predicted low water, when possible, in accordance with the Project Letter Instructions, Standing Instructions and the FPM. The general limit of safe navigation for the survey launches and skiff was five to twenty meters offshore of the apparent low-water line. Water depths along this limit of safe navigation were approximately eight meters at Mean Lower-Low Water (MLLW). Significant features unsurveyable by launches were surveyed when possible with the skiff and annotated on hardcopy and digital shoreline fieldsheets. Detached positions (DPs) acquired during shoreline verification surveys were recorded and attributed with a Trimble Pathfinder ProXRS differential-beacon global positioning system (DGPS) receiver. When possible, positions were collected directly over or next to the feature. At times, in order to efficiently utilize tide windows or for safety precautions, object positions were taken from a close distance. A visually estimated offset and a compass determined heading were entered into the GPS before position acquisition. Generally, DPs were acquired to describe new features or changes to features in reference to the CFF source data or chart. Existing features that were accurately positioned in source data were verified in the field and annotated on hardcopy and digital fieldsheets. Features that were not observed by visual search were generally disproved or evaluated in echosounder or multibeam sounding coverage. A detailed shoreline fieldsheet in MapInfo format, is provided with the survey data, showing all detached positions with notes relating to each feature. Additions and changes to source and charted shoreline data were imported to and processed in Caris Notebook 2.2 Beta and are submitted as Caris .HOB files to be opened as a Notebook Field Plot and included in the final digital smooth sheet18 (HCell). D3.3 Source Shoreline Changes and New Features Point features are documented in the Survey Feature Report generated by Pydro located in appendix I. Non point features are not included in the report and are documented as follows. Two pieces of line extending off of a fish pen, S-57 class on the southern shore of Bear Cove were observed. DPs were not taken on these pieces of line. From the south-eastern corner of the fish pen at 57-0-42.71 N, 135-9-18.94 W a line extends at 100 degrees for approximately 2,200 meters to shore. From the south-western corner of the fish pen at 57-0-42.29 N, 135-9-25.89 W a line extends at 210 degrees for approximately 5,200 meters to shore.19 D3.4 Low-Water Shoreline The low-water shoreline was not defined for this project.20 In most areas, the shoreline was steep and dropped off immediately to deep water.

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D3.5 Charted Features Point features are documented in the Survey Feature Report generated by Pydro located in appendix I. Non point features are not included in the report and are documented as follows.

Position S-57 Object Name

Item Description

Shoreline Source Latitude Longitude

Disproval Method

SLCONS log boom CH & CFF 57-02-52.15 135-13-40.10 Visual SLCONS log boom CH & CFF 57-02-49.89 135-13-37.25 100% SWMB SLCONS log boom CH & CFF 57-02-50.40 135-13-35.52 Visual SLCONS log boom CH & CFF 57-02-40.85 135-13-29.58 100% SWMB SLCONS pier CH & CFF 57-02-47.68 135-13-44.64 Visual SLCONS pier CH & CFF 57-02-48.77 135-13-45.29 Visual SLCONS pier CH & CFF 57-02-49.16 135-13-44.45 Visual SLCONS pier CH & CFF 57-02-52.14 135-13-37.19 Visual SLCONS platform CH & CFF 57-02-51.79 135-13-38.22 Visual SLCONS Pier CH 57-01-55.95 135-12-56.58 100% SWMB

Table 1. Disproved CFF and Charted shoreline features within survey limits of H11123.21

Four charted floating log booms, S-57 object class SLCONS, in Sawmill Cove were disproved. Three of the four log booms were disproved after conducting a visual search and obtaining 100% SWMB coverage of the area. The fourth and northern most log boom was disproved by visual search only, as the depths in this area are very shoal (Table 1). Four charted piers, S-57 object class SLCONS, in Sawmill Cove were disproved by visual search. The area was too shoal to collect SWMB for disproval of any remnants of the piers (Table 1.) One charted platform, S-57 object class SLCONS, in Sawmill Cove was disproved by visual search. The area was to shoal to collect SWMB for disproval of any remnants of the platform (Table 1.) Charted log storage, S-57 object class SLCONS, on both sides of Silver Bay and in Bear Cove was disproved visually and by 100% SWMB. Although logs are no longer stored on the water surface, SWMB and SSS data show remnants of logs scattered on the bottom. The remnants do not protrude higher than 0.3 meters off the bottom, thus a note on the chart is not recommended. Charted pier, S-57 object class SLCONS, on the upper western side of Silver bay was disproved visually and by 100% SWMB (Table 1). D3.6 Shoreline Recommendations The Hydrographer recommends that the shoreline features included in the final S-Cell22 supersede and complement shoreline information compiled in the DM, CFF, T-Sheets and charts as noted. These revisions are included in the final digital database as S-57 format feature objects. Field notes, including verification of source features, are submitted with the hard copy shoreline fieldsheet. A digital MapInfo workspace of the final shoreline plot is included with the survey data (shoreline_ver_plot.WOR).

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D.4 Dangers to Navigation and Shoals D4.1 DTONs Six dangers to navigation were found and reported to the Pacific Hydrographic Branch for verification and final submission to the Seventeenth Coast Guard District on March 1, 2005.23 A copy of the preliminary Danger to Navigation Report is included in Appendix I and a copy of the final report will be inserted by PHB following verification and submission to the U.S Coast Guard.

No. Feature

Depth Latitude Longitude TPE Value

1.1 Sounding24 11.51 m 057° 02’ 45.128” N 135° 13’ 42.218” W 0.257 1.2 Sounding 6.63 m 057° 02’ 48.587” N 135° 13’ 40.239” W 0.249 1.3 Sounding 5.79 m 057° 02’ 49.701” N 135° 13’ 37.135” W 0.249 1.4 Sounding 8.10 m 057° 02’ 48.478” N 135° 13’ 36.197” W 0.250 1.5 Sounding 7.96 m 057° 02’ 47.128” N 135° 13’ 34.827” W 0.250 1.6 Sounding 2.87 m 057° 02’ 44.653” N 135° 12’ 33.353” W 0.253

D4.2 Shoals Sawmill Cove is significantly shoaler than charted25 (17326_1, 17326_2). The shoaling is from an abundance of sunken logs (figure 6). The most significant shoaling is represented by DTONs 1.1, 1.2, 1.3, 1.4, and 1.5.

Figure 6. Shoaling in Sawmill Cove caused by sunken logs.

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D.5 Aids to Navigation Survey H11123 included one fixed aid to navigation (ATON), FlG 6s at the mouth of Silver Bay26. The ATON was found to serve its intended purpose. One private uncharted ATON27 was positioned at the mouth of Silver Bay, and is fully attributed in pydro PSS and Caris S-57 exchange files. D.6 Coast Pilot Information

Figure 7. Abandoned wharf and pulpmill in Sawmill Cove

Silver Bay no longer has unlighted log rafts or any floating log storage. The pulp mill in Sawmill Cove is abandoned so the smoke from the pulp mill can no longer be seen in the bay. The bottom of Sawmill Cove is foul with sunken logs and submerged remnants of the pulp mill construction. Herring Cove is no longer used for log storage and there are no remaining dolphins so there is no longer anything for small crafts to tie up to in the cove. The bottom of the entire cove is foul with sunken logs and there is a submerged piling in 57° 02’44.65 N, 135° 12’ 33.35 W. The 1.5 fathom spot in the middle of the entrance remains and caution should still be used when passing. Bear Cove is no longer used for log storage, thus it is no longer an area that small craft can tie up in. The cove now has two fish hatcheries. The main facility is at the head of the cove and a smaller one is located on the southern edge. Information pertaining to Agruello Island is still accurate.

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D.7 Miscellaneous Bottom Samples Bottom samples were collected in accordance with the HSSDM and are submitted as SBDARE objects in the final PSS and Caris S-57 data exchange set.28 D.7 Statistics

Vessel Survey day Linear nmi SVP Bottom Samples

D2 298_04 20.25 5 0 D2 299_04 15.3 7 3 D2 300_04 1.07 1 0 DA 298_04 15.97 4 8 DA 299_04 5.71 2 4 R2 298_04 13.95 5 0 R2 299_04 20.46 4 0 R2 300_04 8.14 5 0 R2 301_04 8.54 3 0 R2 302_04 5.13 2 0

Survey totals:

Survey days Linear nmi Square nmi SVP Bottom Samples

5 114.51 3.19 39 15 D.9 Adequacy of Survey This survey is considered complete and adequate to supercede prior surveys for requirements specified in the Project Letter Instructions. E. APPROVAL As Lead Hydrographer, I have ensured that data acquired during this survey fulfils project requirements and conforms to the NOS Hydrographic Surveys Specifications and Deliverables, as updated for 2004. The digital data and supporting records have been reviewed by me, are considered complete and adequate for charting purposes.29 All records are forwarded for final review and processing to N/CS34, Pacific Hydrographic Branch.

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Survey H11123 is complete and adequate to supersede charted soundings within the scope and coverage of the survey. No additional work is recommended for this survey.30 Listed below are supplemental reports submitted separately that contain additional information relevant to this survey: Title Office Data Acquisition and Processing Report for OPR-O112-TC-04 N/CS34 Horizontal and Vertical Control Report for OPR-O112-TC-04 N/CS34 Tides and Water Levels Package for OPR-O112-TC-04 N/OPS1 Coast Pilot Report for OPR-O112-TC-04 N/CS26

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1 Concur 2 This table shows the assigned “sheet” limits. The actual western limit of the survey is 135-15-15.73W. 3 Filed with project records. 4 Concur. 5 Concur, the Survey Acceptance Review found the data were within IHO order 1 specifications. 6 A Horizontal and Vertical Control report is filed with the project records. 7 Concur, final tides were applied at PHB. 8 PSS feature report is located in Appendix 1. 9 ENC US5AK3VM had not been created at the time survey H11123 was conducted. When comparing ENC US5AK3VM to survey H11123 it was noticed and reported to MCD that the SE corner of Sawmill Cove and the northern half of Herring Cove are missing from the ENC. 10 Concur. 11 Concur, chart area as shown in the HCell. 12 Concur, chart area as shown in the HCell. 13 Although all charted dolphins were disproved visually in Herring Cove there is one dolphin that was not disproved with SWMB. This dolphin has a blue note specifically stating that it is not disproved below the surface. It is recommended that the dolphin be charted as submerged. 14 Concur, added OBSTRN area with CATOBS of “foul ground” that covers all of Herring Cove. 15 Charted a 1 fathom-5 foot obstruction at 57-02-44.641N, 135-12-33.312W. 16 Concur, many soundings have been designated, some of which were carried forward to be soundings and least depths on obstructions as shown in the HCell. 17 Although it was not used the ENC for this area is US5AK3VM. 18 Do not concur. The HCell does not contain a digital smooth sheet. 19 These pieces of line were included in the Notebook files and compiled to the chart as ground tackle, chart as shown in the HCell. 20 In many areas the bathymetry from the BASE surface was sufficient to disprove charted MLLW. These areas are depicted by blue notes in the H11123bluenotes file. 21 Concur with hydrographer’s statements below. Removal recommendations are shown in the blue notes, chart as shown in the HCell. 22 The term S-cell is no longer used. This should say HCell. 23 Do not concur. Seven DTON’s were submitted to MCD. A copy of the DTON reports is attached. 24 All soundings are obstructions, and were charted as such. 25 Concur. Chart area as shown in the HCell 26 This ATON is not within the boundaries of the survey. Use the most current ATONIS information for charting. 27 Item charted as private MORFAC with a light. 28 Concur, bottom samples have been compiled to the Hcell. 29 Concur, the survey is adequate to supersede prior surveys within the common area. 30 Concur

H11123 DTONs

Registry Number: H11123

State: Alaska

Locality: Sitka

Sub-locality: Silver Bay

Project Number: OPR-O112-TC-04

Survey Dates: 10/25/2004 - 10/26/2004

Charts Affected

Number Version Date Scale

17324 13th Ed. 03/25/1989 1:40000

17326 13th Ed. 08/05/2000 1:40000

17320 16th Ed. 12/01/2003 1:217828

16016 20th Ed. 11/01/2003 1:969756

531 22nd Ed. 03/01/2004 1:2100000

500 8th Ed. 06/01/2003 1:3500000

530 30th Ed. 03/23/2002 1:4860700

50 6th Ed. 06/01/2003 1:10000000

Features

No.FeatureType

SurveyDepth

SurveyLatitude

SurveyLongitude

AWOISItem

1.1 Obstruction 11.51 m 057° 02' 45.128" N 135° 13' 42.218" W ---

1.2 Obstruction 6.63 m 057° 02' 48.587" N 135° 13' 40.239" W ---

1.3 Obstruction 5.79 m 057° 02' 49.701" N 135° 13' 37.135" W ---

1.4 Obstruction 8.10 m 057° 02' 48.478" N 135° 13' 36.197" W ---

1.5 Obstruction 7.96 m 057° 02' 47.128" N 135° 13' 34.827" W ---

1.6 Obstruction 2.87 m 057° 02' 44.653" N 135° 12' 33.353" W ---

Generated by Pydro v4.9.3 on Tue Mar 01 16:27:31 2005 [UTC]

1 - Danger To Navigation

1.1) Profile/Beam - 262/101 from h11123 / tpe_d2_mb_0 / 2004-299 /d2mba04299_d34

DANGER TO NAVIGATION

Survey Summary

Survey Position: 057° 02' 45.128" N, 135° 13' 42.218" W

Least Depth: 11.51 m

Timestamp: 2004-299.22:09:04.123 (10/25/2004)

Survey Line: h11123 / tpe_d2_mb_0 / 2004-299 / d2mba04299_d34

Profile/Beam: 262/101

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Obstruction, isolated contact measuring roughly 7m in diameter.

Feature Correlation

Address Feature Range Azimuth Status

h11123/tpe_d2_mb_0/2004-299/d2mba04299_d34 262/101 0.00 000.0 Primary

Hydrographer Recommendations

[None]

Cartographically-Rounded Depth (Affected Charts):

6 ¼fm (17326_2, 17326_1, 17320_1, 16016_1, 530_1)

6fm 2ft (17324_1, 531_1)

11.5m (500_1, 50_1)

S-57 Data

Geo object 1: Obstruction (OBSTRN)

Attributes: INFORM - Obstruction, isolated contact measuring roughly 7m in diameter.

VALSOU - 11.510 m

H11123 DTONs 1 - Danger To Navigation

Page 3



Survey Summary


Least Depth: 6.63 m

Timestamp: 2004-299.22:13:00.584 (10/25/2004)



Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Submerged dolphin

Feature Correlation




[None]


3 ½fm (17326_2, 17326_1, 17320_1, 16016_1, 530_1)

3fm 3ft (17324_1, 531_1)

6.6m (500_1, 50_1)

S-57 Data


Attributes: INFORM - Submerged dolphin

VALSOU - 6.627 m


Page 4



Survey Summary


Least Depth: 5.79 m

Timestamp: 2004-299.22:21:13.761 (10/25/2004)



Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Submerged dolphin

Feature Correlation




[None]


3fm (17326_2, 17326_1, 17320_1, 16016_1, 530_1)

3fm 1ft (17324_1, 531_1)

5.8m (500_1, 50_1)

S-57 Data



VALSOU - 5.785 m


Page 5



Survey Summary


Least Depth: 8.10 m

Timestamp: 2004-299.22:21:40.101 (10/25/2004)



Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Obstruction is shoalest representative contact of surounding debris.

Feature Correlation




[None]


4 ¼fm (17326_2, 17326_1, 17320_1, 16016_1, 530_1)

4fm 2ft (17324_1, 531_1)

8.1m (500_1, 50_1)

S-57 Data


Attributes: INFORM - Obstruction is shoalest representative contact of surounding debris.

VALSOU - 8.100 m


Page 6



Survey Summary


Least Depth: 7.96 m

Timestamp: 2004-299.22:22:17.408 (10/25/2004)



Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Obstruction, DTON is shoalest representative contact of surounding debris.

Feature Correlation




[None]


4 ¼fm (17326_2, 17326_1, 17320_1, 16016_1, 530_1)

4fm 2ft (17324_1, 531_1)

7.9m (500_1, 50_1)

S-57 Data


Attributes: INFORM - Obstruction, DTON is shoalest representative contact of surounding debris.

VALSOU - 7.958 m


Page 7

1.6) Profile/Beam - 163/196 from h11123 / tpe_r2_mb_0 / 2004-300 /r2mba04300b_d26


Survey Summary


Least Depth: 2.87 m

Timestamp: 2004-300.19:12:32.633 (10/26/2004)

Survey Line: h11123 / tpe_r2_mb_0 / 2004-300 / r2mba04300b_d26


Charts Affected: 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Submerged dolphin

Feature Correlation


h11123/tpe_r2_mb_0/2004-300/r2mba04300b_d26 163/196 0.00 000.0 Primary


[None]


1 ½fm (17326_1, 17320_1, 16016_1, 530_1)

1fm 3ft (17324_1, 531_1)

2.8m (500_1, 50_1)

S-57 Data



VALSOU - 2.869 m


Page 8

H11123 DTON


State: Alaska

Locality: Sitka



Survey Date: 10/25/2004

Submerged Dolphin was discovered during chart compilation at PHB.

Charts Affected


17324 13th Ed. 03/25/1989 1:40000

17326 13th Ed. 08/05/2000 1:40000

17320 16th Ed. 12/01/2003 1:217828

16016 20th Ed. 11/01/2003 1:969756

531 22nd Ed. 03/01/2004 1:2100000

500 8th Ed. 06/01/2003 1:3500000

530 30th Ed. 03/23/2002 1:4860700

50 6th Ed. 06/01/2003 1:10000000

Features

No.FeatureType

SurveyDepth

SurveyLatitude

SurveyLongitude

AWOISItem

1.1 Obstruction 3.15 m 057° 02' 46.890" N 135° 13' 38.968" W ---

Generated by Pydro v7.3 (r2014) on Wed Apr 04 20:31:09 2007 [UTC]

1 - Danger To Navigation



Survey Summary


Least Depth: 3.15 m

Timestamp: 2004-299.22:10:56.542 (10/25/2004)



Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

submerged dolphin

Feature Correlation




chart as obstruction


1 ¾fm (17326_2, 17326_1, 17320_1, 16016_1, 530_1)

1fm 4ft (17324_1, 531_1)

3.1m (500_1, 50_1)

S-57 Data


Attributes: VALSOU - 3.153 m

H11123 DTON 1 - Danger To Navigation

Page 3

H11123 AWOIS Items


State: Alaska

Locality: Sitka



Survey Date:

Charts Affected


17324 13th Ed. 03/25/1989 1:40000

17326 13th Ed. 08/05/2000 1:40000

17320 16th Ed. 12/01/2003 1:217828

16016 20th Ed. 11/01/2003 1:969756

531 22nd Ed. 03/01/2004 1:2100000

500 8th Ed. 06/01/2003 1:3500000

530 30th Ed. 03/23/2002 1:4860700

50 6th Ed. 06/01/2003 1:10000000

Features

No.FeatureType

SurveyDepth

SurveyLatitude

SurveyLongitude

AWOISItem

1.1 AWOIS [no data] [no data] [no data] ---











Generated by Pydro v7.3 (r2014_TCfix) on Fri May 04 22:22:18 2007 [UTC]











Page 2

1 - AWOIS Database Items

1.1) AWOIS #53158 - OBSTRUCTION

No Primary Survey Feature for this AWOIS Item

Search Position: 057° 02' 51.650" N, 135° 13' 43.180" W

Historical Depth: [None]

Search Radius: 50

Search Technique: VS,S2,MB,DI

Technique Notes: [None]

History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT 57/02/51.65 N., LON 135/13/43.18 W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Floating log boom visually disproved. 100% SWMB revealed no remnants of the log boom.

Feature Correlation


OPR-O112-TC-04 AWOIS # 53158 0.00 000.0 Primary

H11123_dp_MORFAC_point.shp 6 5.74 295.9 Secondary


[None]

S-57 Data

Geo object 1: Cartographic symbol ($CSYMB)

H11123 AWOIS Items 1 - AWOIS Database Items

Page 4

Office Notes

Concur with field remarks. Remove charted log boom.


Page 5





Search Radius: 50

Search Technique: VS, MB, S2, DI


History Notes:

FE298, MAY 1987; REPORTS THE EXISTANCE OF A DOLPHIN IN LAT. 57/02/44.35 N., LON. 135/13/45.67W. (NAD83)

Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Dolphin verified as is charted.

Feature Correlation




[None]

S-57 Data

Geo object 1: Mooring/warping facility (MORFAC)

Office Notes

Concur with field remarks. Retain charted dolphin.


Page 6





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:

Floating log boom visually disproved.

Feature Correlation




[None]

S-57 Data



Page 7

Office Notes



Page 8





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 9

Office Notes



Page 10





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation





[None]

S-57 Data



Page 11

Office Notes



Page 12





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 13

Office Notes



Page 14





Search Radius: 50



History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT 57/02/24 N., LON 135/13/11.4 W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 15

Office Notes



Page 16





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 17

Office Notes



Page 18





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 19

Office Notes



Page 20





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 21

Office Notes



Page 22





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation





[None]

S-57 Data



Page 23

Office Notes



Page 24





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 25

Office Notes



Page 26





Search Radius: 50



History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT57/02/50.41 N., LON 135/13/40.21 W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 27

Office Notes



Page 28





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 29

Office Notes



Page 30





Search Radius: 50



History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT 57/02/50.19 N., LON 135/13/42.61W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation





[None]

S-57 Data



Page 31

Office Notes



Page 32





Search Radius: 50



History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT 57/02/36 N., LON 135/13/36 W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 33

Office Notes



Page 34





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation





[None]

S-57 Data



Page 35

Office Notes



Page 36





Search Radius: 50



History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT 57/02/48.79N., LON 135/13/39.43W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 37

Office Notes



Page 38





Search Radius: 50



History Notes:

FE298, MAY 1987; REPORTS A LOG BOOM IN NORTHERN HALF OF SAWMILL COVE. THE DRINDICATED THE STRUCTURE AS SEMI-PERMANENT AND NO FIXED POSITIONS WERE GIVEN. ANOBLIQUE AREIAL PHOTO OF THE LONG BOOM WAS INCLUDED IN THE DR. THE SMOOTH SHEETFOR THE DR INDICATES THE EXTENT OF THE LOG BOOM AND IS THE APARENT SOURCE OF THECHARTED DOLPHIN IN LAT 57/02/31 N., LON 135/13/23 W. (NAD83) (KRW 9/8/2004)

Survey Summary

Charts Affected: 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 39

Office Notes



Page 40





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation





[None]

S-57 Data



Page 41

Office Notes



Page 42





Search Radius: 50



History Notes:


Survey Summary

Charts Affected: 17326_2, 17324_1, 17326_1, 17320_1, 16016_1, 531_1, 500_1, 530_1, 50_1

Remarks:


Feature Correlation




[None]

S-57 Data



Page 43

Office Notes



Page 44

1

H-11123 H-Cell Supplemental Report

Peter Holmberg, Physical Scientist Pacific Hydrographic Branch

Introduction The primary purpose of the H-Cell is to directly update NOAA ENCs with new survey information in International Hydrographic Organization (IHO) format S-57. H-Cell compilation of survey H-11123 utilized Office of Coast Survey H-Cell Specifications Version 2.0, April 2, 2007. H-Cell H-11123 will be used to update chart 17326,1:40,000 with an inset of 1:5,000 for Sawmill Cove (7th Ed.; March, 2004, NM 4/17/2007) and US5AK3VM. 1. Compilation Scale

The density of soundings in the H-Cell are compiled as appropriate to emulate those soundings of Chart 17326, 1:40,000 and 1:5,000 for the inset which is compiled in place. Position and density of non-bathymetric features included in the H-Cell have not been generalized from the scale of the hydrographic survey, 1:10,000. 2. Soundings

2.1 Source Data

A 5 meter resolution Combined BASE surface, H11123_5m_cmbd was used as the basis for H-Cell production following Branch certification. For the purposes of attributing the M_QUAL areas and the TECSOU of each sounding in the h-cell multibeam and singlebeam have to be kept separate during the compilation process. For multibeam data a survey-scale full density sounding (SOUNDG) feature object source layer was built from the H11123_5m_cmbd surface in CARIS BASE Editor. A shoal-biased selection was made at 1:10,000 survey scale using a radius table with values shown in Table 1. The same process was repeated at 1:1,250 for the inset area. The sounding feature object source layer was exported from BASE Editor as H11123_MB_SNDGS, and imported into HOM. For singlebeam data a survey-scale full density sounding (SOUNDG) feature object source layer was built from the H11123_10m surface in CARIS BASE Editor. A shoal-biased selection was made at 1:10,000 survey scale using a radius table with values shown in Table 1, below. The same process was repeated at 1:1,250 for the inset area. The sounding feature object source layer was exported from BASE Editor as H11123_SB_SNDGS, and imported into HOM.

2

Upper limit (m) Lower limit (m) Radius (mm)

0 10 3 10 20 4 20 50 4.5 50 130 5

Table 1

2.2 Sounding Feature Objects

In CARIS BASE Editor soundings were manually selected from the high density sounding layers, H11123_MB_SNDGS, and H11123_SB_SNDGS, and imported into new layers created to accommodate chart density depths. Manual selection was used to accomplish a density and distribution that more closely represents the seafloor morphology and that emulates density and distribution of soundings on chart 17326 than is possible using automated methods. See section 10.1, Data Processing Notes, for details about the use of manual sounding selection for H11123. The sounding feature object source layers were exported as H11123_MB_SNDGS_CS, and H11123_SB_SNDGS_CS and imported into HOM. 3. Depth Areas

3.1 Source Data

The BASE surfaces H11123_5m_cmbd, and H11123_10m were used to generate all encompassing depth areas, and, for survey evaluation and verification purposes only, sets of chart equivalent contours. No actual depth contours were delivered per OCS H-Cell Specifications ver. 2.0.

3.2 Depth Area Feature Objects

One all-encompassing depth range, 0 meters to 150 meters, was used for all depth area objects below MLLW. Upon conversion to NOAA charting units, this depth range is 0 fathoms to 67 fathoms. Six separate depth areas were created for shoreline features located beyond the extents of hydrography. Depth ranges for the areas were taken directly from the ENC.

4. Meta Areas

The following Meta object areas are included in H-Cell 11123:

M_QUAL M_NSYS M_COVR M_CSCL

3

Meta area objects were constructed on the basis of perimeter lines delineating the surveyed limits, “islands of coverage” for point and line features surveyed outside the hydrographic limits, and extents of data gaps inside the survey area. These perimeters were first used to create the Skin of The Earth (SOTE) layer, then were duplicated to the Meta object layers and attributed per the H-Cell Specifications, ver. 2.0. 5. Survey Features

All features for H11123 are fully documented with attribution and action taken during compilation in H11123_Features.xls. The following are brief descriptions of the tabs within the spreadsheet.

AWOIS Twenty-one AWOIS Items were assigned to the survey. All of the items except for one were in reference to log booms which have been disproved. The remaining item was for a dolphin which was confirmed to be correctly charted. Designated Soundings and DtoNs The survey contained 75 designated soundings, six of which were DtoNs. During office processing one additional DtoN was discovered. The DtoN was applied to the h-cell and reported to MCD, making for a total of 76 designated soundings and seven DtoNs. The remainder of the designated soundings represented many shoal points densely located in Sawmill Cove. Due to the density of the designated soundings being greater than the density of the charted soundings not all were selected, although all designated soundings are in the survey scale density sounding set. ATONs H11123 did not contain any federally maintained ATONs. One private lighted mooring buoy is located just inside the entrance to Silver Bay. The private mooring buoy can be used to aid navigation. It is noteworthy that this feature contains the first PICREP submitted with the survey. Shoreline Features Shoreline features for H11123 were delivered in four different files. Despite the descriptive titles of each file the action taken during compilation did not always match hydrographers recommendation based on which file each feature was delivered in.

• H11123_Add_Features • H11123_Modify_Features • H11123_Delete_Features • H11123_Retain_Features

4

6. Shoreline / Tide Delineation Depth areas (DEPARE) and Seabed areas (SBDARE) were created for all SOTE features. 7. Attribution

All S-57 Feature Objects have been attributed as fully as possible based on information provided by the Hydrographer and in accordance with OCS H-Cell Specifications, ver. 2.0. 8. Layout

8.1 CARIS HOM Layering Scheme

100 Chart scale soundings 101 Survey scale soundings 200 Group 1 objects (Skin of the Earth) 300 Point objects 500 Area objects 600-603 Meta layers 800 Items used for creation of Blue Notes 801 Items used for creation of Blue Notes specific to ENC.

8.2 Blue Notes

Notes regarding data sources are in CARIS HOM as layer 800 as Shapefile sets, H11123bluenotes_p and H11123_bluenotes_l (with the appropriate extensions) for point and line figures, respectively. Notes specifically regarding data sources for the ENC are in CARIS HOM as layer 801 as Shapefile sets, H11123bluenotesenc_p and H11123_bluenotesenc_l (with the appropriate extensions) for point and line figures, respectively. 9. Spatial Framework

9.1 Coordinate System

All spatial map and base cell file deliverables are in an LLDG geographic coordinate system, with WGS84 horizontal, MHW vertical, and MLLW (1983-2001 NTDE) sounding datums.

5

9.2 Horizontal and Vertical Units

During creation of sounding sets in CARIS BASE Editor, and creation of the H-Cell in CARIS HOM, units are maintained as metric with millimeter resolution. NOAA rounding is applied at the same time that conversion to chart units is made to the metric H-Cell base cell file, at the end of the H-Cell compilation process. A CARIS environment variable, uslXsounding_round, controls the depth at which rounding occurs. Setting this variable to NOAA fathoms and feet displays all soundings from 0 to equal to or greater than 11 fathoms as whole units. In an ENC viewer fathoms and feet display in the format X.YZZZ, where X is fathoms, Y is feet, and ZZZ is decimals of the foot. For fathoms and feet between 0 and 10 fathoms 4.5 feet (10.75 fms), soundings round to the deeper foot if the decimals of the foot are X.Y75000 or greater. For fathoms and feet deeper or equal to 11 fathoms, soundings round to the deeper fathom if feet and decimals of the foot are X.45000 (X.Y75000) or greater. Drying heights are in feet and are rounded using arithmetic methods. In an ENC viewer, heights greater than 6 feet will register in fathoms and feet using the above stated rules. HOM Units

Sounding Units: Meters rounded to the nearest millimeter Spot Height Units: Meters rounded to the nearest meter

Chart Unit Base Cell Units

Depth Units (DUNI): Fathoms and feet Height Units (HUNI): Feet (or fathoms and feet above 6 feet) Positional Units (PUNI): Meters

10. QA/QC

10.1 Data Processing Notes

Manual chart scale sounding selections were made for this survey. Experience has shown that in areas where bathymetry is steep sided, as in the case of this extremely steep edged fjord, automated sounding selection is impractical. None of the default sounding suppression options offered in CARIS BASE Editor or HOM yields an acceptable density and distribution of depths, generally bunching soundings nearshore with too sparse coverage seaward. While the customized options are more practical for this type of terrain, an inordinate amount of time must be spent in experimentation with variations on the algebraic terms in order to devise the most suitable formula, and manual adjustments are still required to the resulting sounding set.

6

10.2 ENC Validation Checks

H11123 was subjected to QA and Validation checks in HOM prior to exporting to the H-Cell base cell (000) file. Full millimeter precision was retained in the export of the metric S-57 base cell data set. This data set was converted to a chart unit 000 file. dKart Inspector 5.0 (Service Pack 1) was then used to further check the data set for conformity using the S-58 ver. 2 standard (formerly Appendix B.1 Annex C of the S-57 standard). All tests were run and errors investigated and corrected where necessary.

11. Products

11.1 HSD, MCD and CGTP Deliverables

• H11123 Base Cell File, Chart Units, Soundings compiled to 1:40,000 (1:5,000 inset) • H11123 Base Cell File, Chart Units, Soundings compiled to 1:10,000 (1:1,250 inset) • H11123 Descriptive Report including end notes compiled during office processing

and certification • H11123 H-Cell Supplemental Report • Blue Notes shape files • BAG (Bathymetry Attributes Grid) • 000 Features File

11.2 File Naming Conventions

HOM file set prefix: H11123_hc MCD Chart units base cell file: US511123_CU.000 MCD Chart units base cell file, survey scale soundings: US511123_SS.000 BAG (for CGTP): H11123_5m.bag Features File (for CGTP): H11123_Features.000

7

11.3 Software

HIPS 6.1: Management and inspection of Combined BASE surfaces BASE Editor 1.0: Combination of Product Surfaces and initial creation of the S-57 bathymetry-derived features BASE Editor 2.0: Creation of BAG deliverable CARIS Notebook 2.2: Management and inspection of shoreline files HOM 3.3: Assembly of the H-Cell, S-57 products, QA GIS 4.4a: Setting the sounding rounding variable Pydro v7.3 (r2014_TCfix) Creation of AWOIS and DTON reports dKart Inspector 5.0: Validation of the base cell file 12. Contacts

Inquiries regarding this H-Cell content or construction should be directed to: Peter Holmberg, Physical Scientist, PHB, Seattle, WA; 206-526-6843; [email protected].

APPROVAL SHEET H-11123 Initial Approvals: The survey evaluation and verification has been conducted according to branch processing procedures and the H-Cell compiled per the latest OCS H-Cell Specifications. The survey and associated records have been inspected with regard to survey coverage, delineation of the depth curves, development of critical depths, S-57 classification and attribution of soundings and features, cartographic characterization, and verification or disproval of charted data within the survey limits. The survey records and digital data comply with OCS requirements except where noted in the Descriptive Report and are adequate to supersede prior surveys and nautical charts in the common area. I have reviewed the H-Cell, accompanying data, and reports. This survey and accompanying digital data meet or exceed OCS requirements and standards for products in support of nautical charting except where noted in the Descriptive Report.

H11123 HCell Approval DigSig

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