Slide Menu
Search Help Show/Hide Menu
Short Citation:
OCM Partners, 2024: 2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Lewis County,

Item Identification

Title: 2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Lewis County
Short Name: wa2005_pslc_lewiscounty_m2586_metadata
Status: Completed
Publication Date: 2013-10-30

Terrapoint collected Light Detection and Ranging (LiDAR) data for the Lewis County project of 2005. The project site covered approximately 223 square miles, divided into two blocks: southern block 213 Square Miles, northern block 10 Square Miles. The field data collection took place from December 11th, 2004 to January 30th, 2005. LIDAR data was collected on 12/11/2004, 12/12/2004, 12/15/2004, 1/20/2005, 1/21/2005, 1/24/2005 and 1/30/2005. The control network and check point surveys were established from December 11th to December 23rd, 2004.

The Airborne LiDAR survey was conducted using Terrapoint's 40 kHz ALTMS (Airborne Laser Terrain Mapping System), flying at an optimum height of 3500 ft AGL at 140 knots. The system consists of a 36-degree full angle laser, a Trimble 4700 GPS receiver and a Honeywell H764 IMU unit. This metadata is a collaboration of metadata reports from each of the individual 15 projects. The Puget Sound Lowlands project covers more areas over 2000-2004, these areas were excluded for this project.


The purpose of this project is to provide a high quality DEM and contours of the site for the Lewis County Public Works Department.

The LAS files can be used to create DEMs and also to extract topographic data in software that does not support raster data. Other surface features can also be extracted with custom applications. LiDAR data has a wide range of uses such as earthquake hazard studies, hydrologic modeling, forestry, coastal engineering, roadway and pipeline engineering, flood plain mapping, wetland studies, geologic studies and a variety of analytical and cartographic projects.



Supplemental Information:

A footprint of this data set may be viewed in Google Earth at:

Reports explaining collection and quality assurance is available at:


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category
None LAZ

Physical Location

Organization: Office for Coastal Management
City: Charleston
State/Province: SC

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: As Needed
Data Presentation Form: las
Entity Attribute Overview:

LiDAR points in LAZ format (ASPRS Classes 1,2,7)

Entity Attribute Detail Citation:


Distribution Liability:

Any conclusions drawn from the analysis of this information are not the responsibility

of Terrapoint, PSLC, NOAA, the Office for Coastal Management or its partners.

Data Set Credit: Please credit the Puget Sound LiDAR Consortium (PSLC) for these data. The PSLC is supported by the Puget Sound Regional Council, the National Aeronautical and Space Administration (NASA), the United States Geological Survey (USGS) and numerous partners in local, state, and tribal government.

Support Roles

Data Steward

CC ID: 692201
Date Effective From: 2013-10-30
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


CC ID: 692203
Date Effective From: 2013-10-30
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Metadata Contact

CC ID: 692204
Date Effective From: 2013-10-30
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Point of Contact

CC ID: 692202
Date Effective From: 2013-10-30
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 1134829
W° Bound: -123.12404559
E° Bound: -122.59425408
N° Bound: 46.7648815
S° Bound: 46.3864575

Extent Group 1 / Time Frame 1

CC ID: 1134828
Time Frame Type: Range
Start: 2004-12-11
End: 2005-01-30

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Data Access Procedure:

This data can be obtained on-line at the following URL:


Data Access Constraints:


Data Use Constraints:

Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. These data depict the heights at the time of the survey and are only accurate for that time.

Distribution Information

Distribution 1

CC ID: 743288
Download URL:
File Name: Customized Download

Create custom data files by choosing data area, product type, map projection, file format, datum, etc.

Distribution 2

CC ID: 743289
Download URL:
File Name: Bulk Download

Simple download of data files.



CC ID: 743291
URL Type:
Online Resource


CC ID: 743292
URL Type:
Online Resource


CC ID: 743293
Name: Browse Graphic
URL Type:
Browse Graphic
File Resource Format: kmz

This graphic shows the lidar coverage for the 2005 Lewis County project area in Washington.

Activity Log

Activity Log 1

CC ID: 692220
Activity Date/Time: 2016-05-23

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 692219
Activity Date/Time: 2017-11-14

Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using '' script. Contact Tyler Christensen (NOS) for details.

Activity Log 3

CC ID: 718751
Activity Date/Time: 2018-02-08

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 743290
Activity Date/Time: 2018-03-13

Partial upload to move data access links to Distribution Info.

Data Quality


Elevations are recorded in floating-point meters and the vertical datum is ellipsoidal (GEOID03). There are no other attribute tables.

Horizontal Positional Accuracy:

Horizontal positional accuracy for LiDAR is dependent upon

the quality of the GPS/INS solution, sensor calibration and ground conditions at the time of

data capture. The standard system results for horizontal accuracy are less than 1 meter.

; Quantitative Value: 0.60 meters, Test that produced the value:

Reporting highest reported values with uncertainty of likelihood of less than 0.60 m horizontal accuracy

values. 20 - 60 centimeters on all but extremely hilly terrain.

Vertical Positional Accuracy:

Laser point returns were optimized for internal consistency based on independent data from the LiDAR system, IMU, and aircraft. Noise points (e.g. pits and birds) were filtered from the data based on known elevation ranges. This data was then compared to 960 real time kinematic ground survey points collected to verify the vertical and horizontal accuracies of the data set.; Quantitative Value: 0.25 meters, Test that produced the value: Averaged to 25 cm. 15-15 centimeters on Hard Surfaces (roads and buildings), 15-25 centimeters on Soft/Vegetated Surfaces (flat to rolling terrain), 25-40 centimeters on Soft/Vegetated Surfaces (hilly terrain)

Completeness Report:

LiDAR data has been collected and processed for all areas within the project study area.

Conceptual Consistency:

LiDAR flight lines have been examined to ensure that there was at least 50% sidelap, there are no gaps between flightlines, and overlapping flightlines have consistent elevation values.

Shaded relief images have been visually inspected for data errors such as pits, border artifacts, gaps, and shifting. The data was examined at a 1:3500 scale.


Process Steps

Process Step 1

CC ID: 1134824

Point Generation.

The points are generated as Terrascan binary Format using Terrapoint's proprietary Laser Postprocessor Software. This software combines the Raw Laser file and GPS/IMU information to generate a point cloud for each individual flight. All the point cloud files encompassing the project area were then divided into quarter quad tiles. The referencing system of these tiles is based upon the project boundary minimum and maximums. This process is carried out in Terrascan.

The bald earth is subsequently extracted from the raw LiDAR points using Terrascan in a Microstation environment. The automated vegetation removal process takes place by building an iterative surface model. This surface model is generated using three main parameters: Building size, Iteration angle and Iteration distance.

The initial model is based upon low points selected by a roaming window and are assumed to be ground points. The size of this roaming window is determined by the building size parameter. These low points are triangulated and the remaining points are evaluated and subsequently added to the model if they meet the Iteration angle and distance constraints (fig. 1). This process is repeated until no additional points are added within an iteration.

There is also a maximum terrain angle constraint that determines the maximum terrain angle allowed within the model.

Multiple process dates, report compiled 20050331.

Process Step 2

CC ID: 1134825


1. Flight lines and data were reviewed to ensure complete coverage of the study area and positional accuracy of the laser points.

2. Laser point return coordinates were computed using the REALM survey suite and PosPac based on independent data from the LiDAR system, IMU, and aircraft.

3. The raw LiDAR file was assembled into flight lines per return with each point having an associated x, y, and z coordinate.

4. Visual inspection of swath to swath laser point consistencies within the study area were used to perform manual refinements of system alignment.

5. Custom algorithms were designed to evaluate points between adjacent flight lines. Automated system alignment was computed based upon randomly selected swath to swath accuracy measurements that

consider elevation, slope, and intensities. Specifically, refinement in the combination of system pitch, roll and yaw offset parameters optimize internal consistency.

6. Noise (e.g., pits and birds) was filtered using REALM software tools based on known elevation ranges and included the removal of any cycle slips.

7. Using TerraScan and Microstation, ground classifications utilized custom settings appropriate to the study area.

8. The corrected and filtered return points were compared to the RTK ground survey points collected to verify the vertical and horizontal accuracies.

9. Points were broken into processing bins and output areas and output as laser points, TINed and GRIDed surfaces. Bare earth DEMs meet PSLC specifications.

Process Step 3

CC ID: 1134826

The NOAA Office for Coastal Management (OCM) downloaded topographic files in text format from PSLC's website. The files contained lidar easting, northing, elevation, intensity, return number, class, scan angle and GPS time measurements. The data were received in Washington State Plane South Zone 4602, NAD83 coordinates and were vertically referenced to NAVD88 using the Geoid03 model. The vertical units of the data were feet. OCM performed the following processing for data storage and Digital Coast provisioning purposes:

1. The All-Return ASCII txt files were parsed to convert GPS Week Time to Adjusted Standard GPS Time.

2. The All-Return ASCII files were converted from txt format to las format using LASTools' txt2las tool and reclassified to fit the OCM class list, N=1 (unclassified), G=2 (ground), B=7 (low point/noise)

3. The las files were converted from orthometric (NAVD88) heights to ellipsoidal heights using Geoid03.

4. The las files' vertical units were converted from feet to meters, removing bad elevations.

5. The las files were converted from a Projected Coordinate System (WA SP South) to a Geographic Coordinate system (NAD83)

6. The las files' horizontal units were converted from feet to decimal degrees and converted to laz format.

Process Date/Time: 2013-10-01 00:00:00

Catalog Details

Catalog Item ID: 50146
GUID: gov.noaa.nmfs.inport:50146
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-15 15:24+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2022-08-09 17:11+0000
Metadata Record Published: 2022-03-16
Owner Org: OCMP
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Last Review Date: 2022-03-16
Metadata Review Frequency: 1 Year
Metadata Next Review Date: 2023-03-16