King County Digital Ground Model Data Sources

Frequently-anticipated questions:

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

What does this data set describe?

1. How should this data set be cited?

   County, King, 20110518, King County Digital Ground Model Data Sources: King County, King County, WA.

   Online Links:

   • \\gisimage\images\FTPData\DataStage\dgm_source\dgm_source

   Other_Citation_Details: None

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -122.569581

   East_Bounding_Coordinate: -121.005504

   North_Bounding_Coordinate: 47.966230

   South_Bounding_Coordinate: 47.048751

3. What does it look like?

   <http://www5.kingcounty.gov/sdc/DataImages/dgm_source.jpg> (JPG)

   JPG File of layer overlain on base of WA counties or local cities

4. Does the data set describe conditions during a particular time period?

   Calendar_Date: 2002

   Time_of_Day: 2011

   Currentness_Reference: publication date

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

   Geospatial_Data_Presentation_Form: vector digital data

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):

      • G-polygon (22)

   2. What coordinate system is used to represent geographic features?

      The map projection used is Lambert Conformal Conic.

      Projection parameters:

      Standard_Parallel: 47.500000

      Standard_Parallel: 48.733333

      Longitude_of_Central_Meridian: -120.833333

      Latitude_of_Projection_Origin: 47.000000

      False_Easting: 1640416.666667

      False_Northing: 0.000000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.000250
      Ordinates (y-coordinates) are specified to the nearest 0.000250
      Planar coordinates are specified in survey feet

      The horizontal datum used is D_North_American_1983_HARN.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Encoding_Method:

      Explicit elevation coordinate included with horizontal coordinates

      Altitude_Resolution: 1.000000

      Altitude_Datum_Name: North American Vertical Datum of 1988

      Altitude_Distance_Units: feet

7. How does the data set describe geographic features?

   maint.GISC.dgm_source_area

   Polygon attribute table (Source: ESRI)

   OBJECTID

   Internal feature number. (Source: ESRI)

   Sequential unique whole numbers that are automatically generated.

   SHAPE

   Feature Geometry (Source: ESRI)

   Coordinates defining the features

   DATA_SOURCE

   Code for data source (Source: King County)

   Value	Definition
   3D04	3di West Snoqualmie, White and Green Rivers 2004 stereo photo control
   KC_LOW	King County Lowland Project 2002 - Lidar bare earth point data
   KC_USGS	USGS DEM and King County joined to complete full 7500 tile
   NOAA	National Oceanic and Air Administation bathymetric point data of various vintages
   PSLC	Puget Sound Lidar Consortium 2002 - Terrapoint bare earth data extracted from all return records
   PSLC_KC	Puget Sound Lidar Consortium and King County joined to create full tile using best data from either
   USGS	United States Geological Survey 10 M DEM
   WADOE	Washington Department of Ecology bathymetry data (contour converted to TIN)
   WS09	2009 Watershed Sciences LiDAR DGM (bare earth) ascii point data for Snoqualmie at Carnation North, Snoqualmie at Carnation South, South Fork Snoqualmie, Newaukum Creek and Lower White River
   WS10	2010 Watershed Sciences LiDAR DGM (bare earth) ascii point data for Cedar River

   SERIAL_ID

   Unique identifier fore each source (Source: King County)

   Integer

   DESCRIP

   Name of data source project (Source: King County)

   Name of project or data source in mixed case

   TILESUFFIX

   File suffix for tile in elevation ascii database (Source: King County)

   Value	Definition
   3d04	Ascii tile from 3D04 data source
   gs	Ascii tile from USGS data source
   jb	Ascii tile contains NOAA or WADOE bathymetry data source
   jn	Ascii tile contains data from both King County and PSLC lidar projects
   js	Ascii tile contains data from both USGS and King County
   kc	Ascii tile contains data from either King County upland or lowland project
   ps	Ascii tile contains data from PSLC project
   ws09	Ascii tile contains data from Watershed Sciences project
   ws10	Ascii tile contains data from Watershed Sciences project

   Shape.area

   Polygon area (Source: ESRI)

   Area in feet

   Shape.len

   Polygon perimeter (Source: King County)

   Perimeter in feet

   Entity_and_Attribute_Overview: None

   Entity_and_Attribute_Detail_Citation: None

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • King County

2. Who also contributed to the data set?

3. To whom should users address questions about the data?
   Mike Leathers
   King County GIS Center
   GIS Data Coordinator
   201 S Jackson St, Suite 706
   Seattle, WA 98104
   USA
   

   206-263-4867 (voice)
   

Why was the data set created?

King County's Elevation (digital ground model - DGM) Database has at its core a high-resolution base from lidar collected in 2002 and 2003. As new elevation data becomes available to infill missing areas (i.e., other sources for bathymetry data as lidar does not collect water areas), or becomes available that improves on the existing lidar base, it is appended to the elevation database.

Where necessary, users may wish to obtain the source and vintage of information in the current database by using this map (or its underlying datafile - p_dgm_source.shp).

The source data file also serves as an index to the various raw data files (zipped ascii files) that may exist for a given area in a location where multiple sources overlap.

How was the data set created?

1. From what previous works were the data drawn?

2. How were the data generated, processed, and modified?

   Date: 26-Mar-2009 and ongoing (process 1 of 5)

   File p_dgm_source.dbf is updated with new source information. DGM_SOURCE_AREA is created by appending all p_'source name' shp files found in references\extents. The p_dgm_source.dbf table is then joined to the appended layer.

   Date: 18-May-2011 (process 2 of 5)

   Added Watershed Science 2010 LiDAR data polygon

   Data sources used in this process:

   • O:\Intranet\SoftMigr\XMLDocs\NewDocuments\dgm_source.xml

   Date: 01-Jun-2011 (process 3 of 5)

   Metadata imported.

   Data sources used in this process:

   • C:\temp\ptempmetadata.xml

   Date: 01-Jun-2011 (process 4 of 5)

   Dataset copied.

   Data sources used in this process:

   • \\gisdw\kclib\plibrary2\survey\shapes\polygon\dgm_source

   Date: 01-Jun-2011 (process 5 of 5)

   Dataset copied.

   Data sources used in this process:

   • \\gisimage\images\FTPData\AllShapeFiles\survey\dgm_source

3. What similar or related data should the user be aware of?

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

1. How well have the observations been checked?

   None

2. How accurate are the geographic locations?

3. How accurate are the heights or depths?

4. Where are the gaps in the data? What is missing?

   The project area source polygons cover the entire extent of the elevation database.

5. How consistent are the relationships among the observations, including topology?

   Project area boundaries define extent of each projects contribution to the underlying 7500 data tile. Where project areas overlap, multiple versions of the tile will exist, each with a unique suffix defining the data sources in that tile. A tile is named with the most recent data source suffix even if the newest source contributes only a small portion to the extent of the new tile.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: None

Use_Constraints:

King County data are made available with the understanding that they shall be used exclusively by the obtainer or his/her authorized agents. Digital products may not be reproduced or redistributed in any form or by any means without the express written authorization of King County.

1. Who distributes the data set? (Distributor 1 of 1)
   Cheryl Wilder
   KCGIS Center
   Data Sales Coordinator
   201 S Jackson St, Suite 700
   Seattle, WA 98104
   USA
   

   206-263-5220 (voice)
   

2. What's the catalog number I need to order this data set?

   /plibrary2/survey/shapes/polygon/dgm_source.shp

3. What legal disclaimers am I supposed to read?

   King County disclaims any warranty of use of any digital product or data beyond that for which it was designed.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	ESRI Shapefile
     Network links:	\\gisdw\kclib\plibrary2\survey\shapes\polygon\dgm_source.shp
     Media you can order:	Yes (format CD or DVD Read-only media, if offline)

   • Cost to order the data:

     Contact KCGIS Client Services for the cost of reproduction - <http://www.kingcounty.gov/operations/GIS/GISData/GISDataDistribution.aspx>

Who wrote the metadata?

Dates:

Last modified: 18-May-2011

Metadata author:

King County GIS Center
c/o Mike Leathers
GIS Data Coordinator
201 S Jackson St, Suite 706
Seattle, WA 98104
USA

206-263-4867 (voice)
firstname.lastname@kingcounty.gov

Metadata standard:

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

Metadata extensions used:

• <http://www.esri.com/metadata/esriprof80.html>