2009 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: San Juan County and Lummi
This kmz file shows the extent of coverage for the 2009 PSLC San Juan County and Lummi
Island lidar data.
The dataset encompasses portions of San Juan and Whatcom counties in northwest Washington.
The surveyed area is approximately 222 square miles. The LAS V1.1 files are classified
into Class 1 (Unclassified) and Class 2 (Bare Earth) water points are included in
both classes. The LAS files are all-return and also include intensity measurements.
50% overlap was used between flightines, resulting in each area being surveyed twice.
The nominal point spacing of the data is 0.408 meters (6 pt/sq. meter). Watershed
Sciences, Inc. collected the LiDAR and created this data set for the Puget Sound LiDAR
Cite this dataset when used as a source.
|Search and Download
|| Distributor information not available
| Point of Contact
Puget Sound Lidar Consortium (PSLC)
Lidar Dataset Supplemental Information
- Diana Martinez
Puget Sound Lidar Consortium (PSLC)
|Data Presentation Form:
|| Digital image
|Dataset Progress Status
|Data Update Frequency:
|| As needed
||Provide high resolution terrain elevation and land cover elevation data.
||2009-02-13 to 2009-04-30
|Spatial Reference System:
|Spatial Bounding Box Coordinates:
|Spatial Coverage Map:
- elevation data
- Remote Sensing
- bare earth
- bare ground
- Whatcom County
- San Juan County
- Lummi Island
| Use Constraints
|| No constraint information available
|| Fee information not available.
|| Lineage statement not available.
| Processing Steps
- Acquisition. The LiDAR data was collected between February 13th-17th, 2009 and April
30th, 2009. The survey used a Leica ALS50 Pase II laser system mounted in a Cessna
Caravan 208B, and an Optech 3100 laser system mounted in a Cessna Caravan 208B. Near
nadir scan angles were used to increase penetration of vegetation to ground surfaces.
Ground level GPS and aircraft IMU were collected during the flight.
- Processing. 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 ALS Post Processor software, IPAS Pro GPS/INS software,
REALM survey suite, and PosPac software, 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 ALS postprocessing software and 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 output as laser points, TINed and GRIDed surfaces.
- Metadata imported.
- The NOAA Coastal Services Center (CSC) received classified topographic files in LAS
V1.1 format. The files contained lidar elevation measurements. The data were received
in Washington State Plane North Zone 4601, NAD83 coordinates and were vertically referenced
to NAVD88 using the Geoid03 model. The vertical units of the data were feet. CSC performed
the following processing for data storage and Digital Coast provisioning purposes:
1. All elevations below -4 feet were filtered and removed using LasTools' las2las
tool. 2. The topographic las files were converted from orthometric (NAVD88) heights
to ellipsoidal heights using Geoid03. 3. The topographic las files were converted
from a Projected Coordinate System (WA SP North) to a Geographic Coordinate system
(NAD 83). 4. The topographic las files' vertical units were converted from feet to
meters. 5. The topographic las files' horizontal units were converted from feet to
decimal degrees. 6. The data were converted to LAZ format.
- The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp
transfer from the NOAA Coastal Services Center. The data are currently
being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/.
The data can be used to re-populate the system. The data are archived in LAS or LAZ
The LAS format is an industry standard for LiDAR data developed by the American Society
of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless compressed version
LAS developed by Martin Isenburg (http://www.laszip.org/). The data are exclusively
in geographic coordinates (either NAD83 or ITRF94). The data are referenced vertically
the ellipsoid (either GRS80 or ITRF94), allowing for the ability to apply the most
up to date geoid model when transforming to orthometric heights.
Metadata Last Modified: 2013-03-28
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