Quantum Spatial
2016
Maine 2015 QL2 LiDAR
USGS Contract: G10PC00026 Task Order Number: G15PD00281
Maine_QL2_2015
Model
Geographic Extent:
Central Maine, covering approximately 2,882 total square miles.
Dataset Description:
The Maine and Massachusetts 2015 QL1 and QL2 LiDAR project called for the Planning, Acquisition, processing and derivative products of LIDAR data to be collected at an aggregate nominal pulse spacing (NPS) of 0.7 meters for the 2,882 sqmi of the QL2 Maine AOI. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base LIDAR Specification, Version 1.2. The data was developed based on a horizontal projection/datum of NAD83 (2011) UTM Zone 19, meters and vertical datum of NAVD1988 (GEOID12A), meters. LiDAR data was delivered in RAW flight line swath format, processed to create Classified LAS 1.4 Files formatted to 3,585 individual 1,500 meter X 1,500 meter tiles. Corresponding 1-meter Intensity Image and 1-meter Bare Earth DEM tiles were created with the same 1,500 meter X 1,500 meter tile schema. Breaklines were produced in Esri shapefile format.
Ground Conditions:
LiDAR was partially collected in spring of 2015 and completed in winter 2015, while no snow was on the ground and rivers were at or below normal levels. In order to post process the LiDAR data to meet task order specifications, Quantum Spatial established a total of 286 Land Cover control points. These were used to calibrate the LIDAR to known ground locations established throughout the entire Maine UTM 19 QL2 project area (136 calibration control points and 150 QC checkpoints).
Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEM.
The purpose of these lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 1 meter cell size.
These raw lidar point cloud data were used to create classified lidar LAS files, intensity images, 3D breaklines and hydro-flattened DEMs as necessary.
USGS Contract: G10PC00026 Task Order Number: G15PD00281
CONTRACTOR: Quantum Spatial
Lidar data were acquired and calibrated by Quantum Spatial, Atlantic, and Precision Aerial Reconnaissance.
All follow-on processing was completed by the prime contractor.
20150504
20151110
ground condition
None planned
-70.1497688465833
-68.2684096932595
45.3645115939012
44.4191288007804
409500.000000
558000.000000
5023500.000000
4918500.000000
None
Elevation data
Lidar
Hydrology
None
Maine
ME
No restrictions apply to this data.
None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data.
Quantum Spatial, Data Acquisition Department
Tobin Guthrie
mailing and physical
523 Wellington Way
Lexington
KY
40503
USA
859-277-8700
859-277-8901
tguthrie@quantumspatial.com
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
If unable to reach the contact by telephone, please send an email. You should get a response within 24 hours.
MicroStation Version 8; TerraScan Version 15; TerraModeler Version 15; GeoCue Version 2014.1.21.1; Esri ArcGIS 10.2; Global Mapper 16; Leica Cloud Pro 1.2; Windows 7 Operating System
\\psihq_nx3200\Projects\26258_Maine_Mass_USGS_LiDAR\ 1.38 TB and \\Matrix\LIDAR\26258_MA_ME_QL1andQL2\ 23.5 TB
Data cover the entire area specified for this project.
These raw LAS data files include all data points collected.
No points have been removed or excluded.
A visual qualitative assessment was performed to ensure data completeness.
No void areas or missing data exist. The raw point cloud is of good quality and data passes Nonvegetated Vertical Accuracy specifications.
The specifications require that Nonvegetated Vertical Accuracy (NVA) be computed for raw lidar point cloud swath files. The vertical accuracy was tested with 84 independent survey located in open terrain. These check points were not used in the calibration or post processing of the lidar point cloud data. The survey check points were distributed throughout the project. Specifications for this project require that the NVA be 19.6 cm or better AccuracyZ at 95 percent confidence level.
The specifications require that Nonvegetated Vertical Accuracy (NVA) be computed for DEM files. The vertical accuracy was tested with 84 independent survey located in open terrain. These check points were not used in the calibration or post processing of the lidar point cloud data. The survey check points were distributed throughout the project. Specifications for this project require that the NVA be 19.6 cm or better AccuracyZ at 95 percent confidence level.
The specifications require that Vegetated Vertical Accuracy (VVA) be computed for DEM files. The vertical accuracy was tested with 65 independent survey located in vegetated terrain. These check points were not used in the calibration or post processing of the lidar point cloud data. The survey check points were distributed throughout the project. Specifications for this project require that the NVA be 29.4 cm or better AccuracyZ at 95 percent confidence level.
0.076
The raw NVA was tested using 84 independent surveys located in open terrain. The survey check points were distributed throughout the project area. The 84 independent check points were surveyed using the closed level loop technique. Elevations from the unclassified lidar surface were measured for the x,y location of each check point. Elevations interpolated from the lidar surface were then compared to the elevation values of the surveyed control. The RMSE was computed to be 0.039 meters and AccuracyZ to be 0.076 meters. AccuracyZ has been tested to meet 19.6 cm NVA at 95 percent confidence level using (RMSEz * 1.9600) as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines.
The NVA was tested using 84 independent surveys located in open terrain. The survey check points were distributed throughout the project area. The 84 independent check points were surveyed using the closed level loop technique. Elevations from the DEM surface were measured for the x,y location of each check point. Elevations interpolated from the DEM surface were then compared to the elevation values of the surveyed control. The RMSE was computed to be 0.038 meters and AccuracyZ to be 0.075 meters. AccuracyZ has been tested to meet 19.6 cm NVA at 95 percent confidence level using (RMSEz * 1.9600) as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines.
The VVA was tested using 65 independent surveys located in vegetated terrain. The survey check points were distributed throughout the project area. The 65 independent check points were surveyed using the closed level loop technique. Elevations from the DEM surface were measured for the x,y location of each check point. Elevations interpolated from the DEM surface were then compared to the elevation values of the surveyed control. The RMSE was computed to be 0.145 meters and AccuracyZ to be 0.286 meters. AccuracyZ has been tested to meet 29.4 cm VVA at 95th percentile level using the 95th percentile of the absolute value of all vertical errors in all combined vegetation classes as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines.
Quantum Spatial
20151020
Survey Report of LiDAR Ground Control and Quality Control Points: Maine
Lexington, KY
Quantum Spatial
online
20150324
20150419
ground condition
ME_2015_LiDAR_gnd_ctrl
This data source was used (along with the airborne GPS/IMU Data) to aid in the georeferencing of the lidar point cloud data.
Quantum Spatial
2015
Lidar RAW Data for Maine QL2 2015
lidar data
Quantum Spatial
2015
online
20150426
20151205
ground condition
ME_QL2_2015_LiDAR_Data
This data source was used to populate the lidar point cloud data.
Quantum Spatial
20151020
Survey Report of LiDAR Ground Control and Quality Control Points: Maine
Lexington, KY
Quantum Spatial
online
20150324
20150419
ground condition
ME_2015_LiDAR_qc_ctrl
This data source was used to QC and vertically adjust the lidar point cloud data.
Hydro-Flattened Breakline Creation:
Class 2 LiDAR was used to create a bare earth surface model. The surface model was then used to heads-up digitize 2D breaklines of inland streams and rivers with a 30 meter nominal width and Inland Ponds and Lakes of 2 acres or greater surface area.
Elevation values were assigned to all Inland Ponds and Lakes, Inland Pond and Lake Islands, Inland Stream and River Islands, using TerraModeler functionality.
Elevation values were assigned to all Inland streams and rivers using Quantum Spatial proprietary software.
All ground (ASPRS Class 2) LiDAR data inside of the collected inland breaklines were then classified to water (ASPRS Class 9) using TerraScan macro functionality. A buffer of 1 meter was also used around each hydro-flattened feature. These points were moved from ground (ASPRS Class 2) to Ignored Ground (ASPRS Class 10).
The breakline files were then translated to Esri file-geodatabase format using Esri conversion tools.
ME_2015_LiDAR_qc_ctrl
ME_QL2_2015_LiDAR_Data
2015
Hydro-Flattened Breaklines
Quantum Spatial
Ryan Griffin
mailing and physical
523 Wellington Way
Lexington
KY
40503
USA
859-277-8700
859-277-8901
rgriffin@quantumspatial.com
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
If unable to reach the contact by telephone, please send an email. You should get a response within 24 hours.
Point
Point
Universal Transverse Mercator
19
0.9996
-69.0
0.0
500000.0
0.0
coordinate pair
0.01
0.01
meters
North American Datum of 1983 (2011)
Geodetic Reference System 80
6378137.0
298.257222101
North American Vertical Datum of 1988 (Geoid12A)
0.01
meters
Explicit elevation coordinate included with horizontal coordinates
Breaklines
A line in a surface that represents a distinct interruption in the slope of a surface, such as a ridge, road, or stream.
Esri GIS Dictionary http://support.esri.com/en/knowledgebase/GISDictionary/term/breakline
FID
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
Esri
Feature geometry - PolylineZM
B_LINE_TY
Breakline Type
LiDAR Data
Lake Pond
LiDAR Data
LAS version 1.4
Lake Pond Island
LiDAR Data
LAS version 1.4
Double Line Drain
LiDAR Data
LAS version 1.4
Double Line Drain Island
LiDAR Data
LAS version 1.4
Bridge
LiDAR Data
LAS version 1.4
Breaklines with the types of Lake Pond, Lake Pond Island, Double Line Drain, Double Line Drain Island, and Bridge.
More detail about the attributes of this data set can be found in LAS 1.4 specifications and USGS LiDAR Base Specification Version 1.2.
20160318
Quantum Spatial
Sarah Zibart
mailing and physical
523 Wellington Way
Lexington
KY
40503
USA
859-277-8700
859-277-8901
szibart@quantumspatial.com
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
If unable to reach the contact by telephone, please send an email. You should get a response within 24 hours.
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
None.
None.
None.
Unclassified
NONE