harvey added some anchors:
lineage
constraints

Washington State Marine Bathymetry Mosaic

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: Washington Department of Fish and Widlife

Publication_Date: 19990701

Title: Washington State Marine Bathymetry Mosaic

Publication_Information:

Publication_Place: Olympia, Washington, USA

Publisher: Washington Department of Fish & Wildlife

Description:

Abstract:

Bathymetry is the measurement of the depth of large bodies of water. Bathymetry data can be stored in a number of formats including point soundings, isobaths (contours), and grids. The bathymetry mosaic dataset is a grid coverage of water depth generated from point soundings. The grid structure is a regular array of cells referenced to the Universal Transverse Mercator (UTM) coordinate system. Each grid cell represents water depth for a discrete 20- x 20-meter area. The mosaic is a continuous grid covering Washington marine waters, Oregon waters as far south as Seaside, and the Columbia River upstream to Bonneville Dam. Canadian marine waters are included for southern Vancouver Island. The dataset was funded by the Puget Sound Ambient Monitoring Program (PSAMP). Primary bathymetry grid processing was performed under contract by Environmental Consultants (ECI), Portland, Oregon.

Purpose:

The bathymetry mosaic is best applied in medium scale applications (e.g., 1:100,000-scale). In regions of high depth sounding density, such as in some regions of Puget Sound, larger scale applications may be possible. The bathymetry mosaic can be readily combined with other spatial data in a Geographic Information Systems (GIS) for scientific study, environmental management, isobath generation, and cartographic display.

Supplemental_Information:

The bathymetry mosaic coastline is defined by highwater line. An additional boundary is defined by low slope areas exposed at low tide, such as mudflats; these areas were excluded from processing due to highly variable sounding availability and mapping consistency.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 1800's

Ending_Date: Present

Currentness_Reference: 19990701

Status:

Progress: complete

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Description_of_Geographic_Extent:

Washington marine waters and Columbia River upstream to Bonneville Dam; Oregon marine waters to as far south as Seaside (46.0 degrees); Canadian waters around southern Vancouver Island. (Puget Sound, Strait of Georgia (limited), Strait of Juan de Fuca, Washington Outer Coast, and Columbia River)

Bounding_Coordinates:

West_Bounding_Coordinate: -126.78

East_Bounding_Coordinate: -121.38

North_Bounding_Coordinate: 49.52

South_Bounding_Coordinate: 45.6

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: bathymetry

Theme_Keyword: depth

Theme_Keyword: isobath

Access_Constraints: None

Use_Constraints:

1. The bathymetry dataset not to be used for navigational purposes. 2. Shoreline detail has been generalized due to grid cell processing. For projects needing fine-scale shoreline detail, it may be necessary to use point soundings and a vector shoreline, as well as additional low/high tide information, for generation of a bathymetry surface. 3. The grid cell depth values in intertidal areas in the bathymetry mosaic may be misleading. The input point soundings are referenced to Mean Lower Low Water (MLLW), and the shoreline represents the high waterline. Thus, sounding interpolation extends from MLLW to the high water line. For larger scale applications the data user may prefer to reconcile low and high tide depths with ancillary intertidal information. 4. Creation of the wide-area mosaic requires a uniform grid cell size. As such, there is a tradeoff between maintaining shoreline detail and interpolation of irregularly spaced soundings. The 20-meter cell size is overly optimistic for some areas given the highly variable depth sounding density observed in the project area. This is especially true for the heavily interpolated offshore region west of a line defined by the coordinates: (46.0, -125) (47.5,-125) (47.5,-125.5) (48.0,-125.5) (48.0,-126)(49,-126).

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Brian Cosentino

Contact_Organization: Washington Department of Fish and Wildlife

Contact_Position: Data Manager

Contact_Address:

Address_Type: mailing address

Address: 600 Capitol Way North

City: Olympia

State_or_Province: Washington

Postal_Code: 98501-1091

Country: USA

Contact_Voice_Telephone: 360-902-2376

Contact_Facsimile_Telephone: 360-902-2162

Contact_Electronic_Mail_Address: cosenblc@dfw.wa.gov.us

Hours_of_Service: 0800 - 1700 Monday through Friday

Native_Data_Set_Environment: UNIX-ARC/INFO

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The accuracy of the bathymetry mosaic is dependent upon an number of factors including density and distribution of depth sounding data, uncertain standards and requirements for soundings acquired before 1965, conversion of Canadian depth data to USA vertical datum, interpolation of sparse, irregularly spaced soundings into a regular grid, and multiple sources and compilation scales of shoreline information. The density and distribution of depth soundings is the most limiting constraint.

Logical_Consistency_Report:

The grid cell data structure is present and is fully operational in GIS environment. The range of depth values is valid. Map coordinate values are valid. Shoreline shape is modeled using a grid cell format. As such, shoreline detail is generalized from the original vector shoreline data.

Completeness_Report:

Most Washington marine waters are contained in the bathymetry mosaic. Data holes exist in Canadian waters in the Strait of Juan de Fuca and south/southwest of Barkley Sound. Limited coverage is provided for Lake Washington.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

A horizontal accuracy assessment was not performed. Note the Hydrographic Manual compiled by the National Ocean Survey for information concerning sounding data standards and requirements.

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report:

A formal comparison between the bathymetry mosaic depth and an independent source of depth data was not performed. A qualitative assessment was performed using digital and hardcopy isobaths obtained from 1:100,000-scale sources, such as the USGS/NOS Bathymetric- Topographic series and the NOAA bathymetric Fishing Map series. The point-to-surface interpolation algorithm provided similar results as found in the 1:100,000-scale map series. Also note the Hydrographic Manual compiled by the National Ocean Survey for information concerning sounding data standards and requirements.

Lineage:

Methodology:

Methodology_Type: Step 1: Shoreline Preparation

Methodology_Identifier:

Methodology_Keyword_Thesaurus: None

Methodology_Description:

Step 1: Four sources of shoreline data were required for this project. The Washington DNR Aquatic Resources' "Water Level Line" provided the bulk of the shoreline. USGS 1:24,000- scale and 1:100,000-scale DLG data were incorporated for the Columbia River shoreline from Portland upriver to the Bonneville Dam. Canadian shoreline information was incorporated for Vancouver Island and the Strait of Georgia.

Methodology_Type: Step 2: Mudlfats/Sand Coverage Preparation

Methodology_Description:

Generation of a master mudflat/sand polygon coverage. This layer, combined with the master shoreline, formed the land/water position.

Methodology_Type: Step 3: Depth Soundings Preparation/Extraction

Methodology_Description:

Preparation of Canadian soundings and extraction of USA soundings from the NOS CD-ROM

Methodology_Type: Step 4: Bathymetry Tile Generation

Methodology_Description:

Fifty-five, 30- x 30-second tiles, generated from interpolated point sounding data, were delivered by the contractor. All interpolation was performed within the GDD reference system.

Methodology_Type: Step 5: Bathymetry Mosaic Generation

Methodology_Description: Generation of mosaic from 55 input tiles

Source_Information:

Source_Citation:

Citation_Information:

Originator: National Ocean Service (NOS)

Originator: Hydrographic Survery Data

Originator: U.S Coastal Waters

Originator: GEODAS CD-ROM Set

Originator: Version 3.3

Publication_Date: 1997

Title: USA Depth Soundings

Geospatial_Data_Presentation_Form: database

Publication_Information:

Publication_Place: Boulder, Colorado

Publisher: National Geophysical Data Center

Type_of_Source_Media: digital database file

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Originator: Canadian Hydrographic Service

Originator: Department of Fisheries and Oceans

Originator: Pacific Region

Title: Digital Field Sheet Soundings

Publication_Information:

Publication_Place: Sidney,British Columbia, Canada

Publisher: Canadian Hydrographic Service

Other_Citation_Details:

Digital Field Sheets: Chart datum: Lower Low Water Large Tide (LLWLT) fs1183L: Race Rocks to Discovery Island 1:25,000 fs1184L: Discovery Island to Morseby Island 1:25,000 fs1190L: William Head to Otter Point 1:20,000 fs1259S: Race Rocks 1:20,000

Type_of_Source_Media: digital file

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Title: Enviromental Chart Depth Data

Publication_Information:

Publisher: Canadian Hydrographic Service

Type_of_Source_Media: digital file

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Originator: Washington State Department of Natural Resources

Originator:

Aquatic Resources Division, Nearshore Habitat Program

Publication_Date: variable

Title: High waterline

Geospatial_Data_Presentation_Form: map

Publication_Information:

Publication_Place: Olympia,Washington,USA

Publisher: Washington Department of Natural Resources

Other_Citation_Details:

"Water Level Line" interpreted from early 1990s digital orthophotography. The water level line compilation scale is 1:24,000. Ancillary digital data include National Wetlands Inventory (NWI) and WADNR Hydrography Framework. Ancillary paper sources include NOAA Navigation Charts and color aerial photographs acquired at low tide. Due to interpretation limitations, the elevation of the water level line may vary from Extreme High Water; therefore, the water line may represent Mean High Water or other elevation regimes in some areas. See WDNR Aquatic Resources' Database documentation for more details.

Source_Scale_Denominator: 24000

Type_of_Source_Media: digital map

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Originator: U.S. Geological Survey

Title: 1:24,000-scale DLG

Other_Citation_Details: http://edcwww.cr.usgs.gov

Source_Scale_Denominator: 24000

Type_of_Source_Media: digital map

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Originator: U.S. Geological Survey

Title: 1:100,000-scale Digital Line Graph

Other_Citation_Details: http://edcwww.cr.usgs.gov

Source_Scale_Denominator: 100000

Type_of_Source_Media: digital map

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Publication_Date: Unknown

Title: Vancouver Island shoreline

Geospatial_Data_Presentation_Form: map

Publication_Information:

Publication_Place: Nanaimo, British Columbia,Canada

Publisher: Department of Fisheries and Oceans

Other_Citation_Details:

Higher High Water Large Tide (HHWLT) line extracted from scanned Canadian Hydrographic Service charts. Scan resolution equals 5 meters. Scanned line converted to vector DXF coverage. Source scale is 1:40,000 except in areas where 1:40,000 not available, then 1:80,000-scale chart data used.

Type_of_Source_Media: digital map

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Publication_Date: variable

Title: Washington State Hydrography Framework

Publication_Information:

Publication_Place: Olympia, Washington, USA

Publisher: Washington State Department of Natural Resources

Source_Scale_Denominator: 24000

Type_of_Source_Media: digital map

Source_Time_Period_of_Content:

Source_Information:

Source_Citation:

Citation_Information:

Publication_Date: variable

Title: Washington State Hydrography Framework

Publication_Information:

Publication_Place: Olympia, Washington, USA

Publisher: Washington State Department of Natural Resources

Source_Scale_Denominator: 24000

Type_of_Source_Media: map

Source_Time_Period_of_Content:

Process_Step:

Process_Description:

Step 1: (1) A master shoreline coverage was generated by appending all shoreline coverages from state, federal, and Canadian sources into one coverage, referenced to UTM Zone 10. (2)A polygon coverage was generated from the master shoreline coverage through addition of new arcs. (3) The polygon coverage was projected to Geographic Decimal Degree (GDD). (4) The polygon shore coverage was exported to an ASCII format and provided to the contractor. (5) The contractor subsequently converted the polygon data into a grid.

Process_Date: 1998

Process_Step:

Process_Description:

Step 2: (1) A master mudflat/sand coverage was generated from Washington Department of Natural Resources' hydrogrpahy framework layer and undocumented Washington Department of Fish and Wildlife coverages. The coverages were joined to create a master mudflat/sand cover and projected from stateplane south to GDD. (2) The polygon coverage was exported to an ASCII format and provided to the contractor. (3) The contractor subsequently converted the polygon data into a grid.

Process_Date: 1998

Process_Step:

Process_Description:

Step 3: (1)Digital Canadian sounding point data were projected from UTM Zone 10, NAD83 to GDD NAD27. (2) The Canadian soundings were adjusted to USA vertical datum using linear regression on a per-area basis. Size of processing area for each regression run was 30- x 30- seconds. An ASCII output was generated of the adjusted soundings and provided to the contractor. (3) Soundings for USA waters were extracted by the contractor from the National Ocean Survey, Hydrographic Survey Data, CD-ROM Set, Version 3.3, 1997. (4) Canadian and USA soundings were combined prior to grid processing.

Process_Date: 1998

Process_Step:

Process_Description:

Step 4: (1) A combined gridded shoreline and mudflat/sand grid was generated. (2) Point soundings were extracted for each 30- x 30-second tile and interpolated to a regular grid structure. Adjacent tiles were edge matched. (3) The grid cell dimensions of nearshore tiles are .00021150592217 x .00021150592217 degrees. Offshore tiles (12 tiles) have grid cell dimensions of .00086805555556 x .00086805555556 degrees. (4) The contractor output each tile in bil image format. Pixel value output as two-byte integer

Process_Date: 1998

Process_Step:

Process_Description:

Step 5: (1) Each tile was imported from bil format to UNIX ARC/INFO/GRID version 7.2 using IMAGEGRID. (2) Processing limitations required each individual tile to be projected/resampled from GDD to UTM Zone 10 prior to mosaic generation. (3) All 55 tiles were combined into one mosaic with grid cell size equal to 20- x 20-meters with non-water areas converted to NODATA.

Process_Date: 1998