2014 ILHMP Lidar: Kankakee County, IL

This dataset is 1 ppsm LiDAR point cloud data and derivative models of Kankakee County, Illinois. Kankakee County is approximately 677 square miles (1753 square kilometers) in north eastern Illinois. Data was collected at a nominal pulse spacing (NPS) of 0.7 meter.

Data acquisition, processing and assessment is compliant with procedures and methods stated in U.S. Geological Survey National Geospatial Program LiDAR Base Specification Version 1.0 and Federal Emergency Management Agency Procedure Memorandum 61.

This dataset consists of LiDAR LAS swath files and tiled LAS files. Tiled LAS files contain LiDAR point information which has been calibrated, controlled, and classified. Tiled LAS and derived data models are named according to the coordinates at the south west corner of the tile.

Quantum Spatial Project No: 1140310.01

This metadata record supports the data entry in the NOAA Digital Coast Data Access Viewer (DAV). For this data set, the DAV is leveraging the Entwine Point Tiles (EPT) hosted by USGS on Amazon Web Services.

LiDAR data collection is used to produce high accuracy surface models of Kankakee County, Illinois in accordance with project requirements.

The LiDAR point cloud data is used to create surface models as requested; classified LiDAR LAS files, Hydro-flattened bare-earth Digital Elevation Models (DEM), shapefiles of breaklines representative of surface hydro features and a ESRI geodatabase of all deliverables.

The following are the USGS lidar fields in JSON:

{

"ldrinfo" : {

"ldrspec" : "USGS NGP Base Specification v1",

"ldrsens" : "Leica ALS70 Serial Number 7161",

"ldrmaxnr" : "4 returns per pulse",

"ldrnps" : "0.64 meters",

"ldrdens" : "2.44 points per meters squared",

"ldrfltht" : "1900 meters",

"ldrfltsp" : "150 knots",

"ldrscana" : "40.0 degrees",

"ldrscanr" : "40.9 Hz",

"ldrpulsr" : "273600 Hz",

"ldrpulsd" : "4 nanoseconds",

"ldrpulsw" : "0.5 meters, 1/3^2",

"ldrwavel" : "1064 nanometers",

"ldrmpia" : "1 [enabled]",

"ldrbmdiv" : "0.15 milliradians",

"ldrswatw" : "1455.88 meters",

"ldrswato" : "17.25%",

"ldrcrs" : "NAD_1983_2011_StatePlane_Illinois_East_FIPS_1201_Ft_US",

"ldrgeoid" : "National Geodetic Survey (NGS) Geoid12A"

},

"ldraccur" : {

"ldrchacc" : "1.00 feet",

"rawfva" : "0.338 feet",

"clscva" : "0.455 feet",

"clssvas" : {

"svalctyp" : "Open Terrain survey points compared to DEM. 95th percentile",

"svavalue" : "0.168 feet"

},

"clssvas" : {

"svalctyp" : "Urban survey points compared to DEM. 95th percentile",

"svavalue" : "0.181 feet"

},

"clssvas" : {

"svalctyp" : "Tall Grass survey points compared to DEM. 95th percentile",

"svavalue" : "0.433 feet"

},

"clssvas" : {

"svalctyp" : "Brush survey points compared to DEM. 95th percentile",

"svavalue" : "0.589 feet"

},

"clssvas" : {

"svalctyp" : "Forest survey points compared to DEM. 95th percentile",

"svavalue" : "0.352 feet"

}

},

"lasinfo" : {

"lasver" : "1.2",

"lasprf" : "1",

"laswheld" : "Withheld (ignore) points were identified in these files using the standard LAS Withheld bit

",

"lasolap" : "There are not Overlap class points in this data.

",

"lasintr" : "8-bit",

"lasclass" : {

"clascode" : "1",

"clasitem" : "Undetermined/Unclassified"

},

"lasclass" : {

"clascode" : "2",

"clasitem" : "Bare-earth"

},

"lasclass" : {

"clascode" : "3",

"clasitem" : "Low Vegetation"

},

"lasclass" : {

"clascode" : "4",

"clasitem" : "Medium Vegetation"

},

"lasclass" : {

"clascode" : "5",

"clasitem" : "High Vegetation"

},

"lasclass" : {

"clascode" : "6",

"clasitem" : "Buildings"

},

"lasclass" : {

"clascode" : "7",

"clasitem" : "All noise"

},

"lasclass" : {

"clascode" : "8",

"clasitem" : "Model Keypoints"

},

"lasclass" : {

"clascode" : "9",

"clasitem" : "Water"

},

"lasclass" : {

"clascode" : "10",

"clasitem" : "Ignored ground"

}

}}

In no event shall the creators, custodians, or distributors of these data be liable for any damages arising out of its use, or from the inability of the customer to use these data for their intended application.

Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners.

Data is available online for bulk and custom downloads.

None

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.

ALS Post Processor 2.75 Build#25; GeoCue Version 13.1.45.1; Windows 7 Operating System

Project specifications require that vertical accuracy, as RMSE, of LiDAR data be less than 9.25 cm in open terrain. Vertical accuracy is determined by comparison of elevation of the ground survey points to DEMs derived from the LiDAR points. Differences are calculated to establish a RMSE.

The FVA is determined using ground survey points collected in "Open Terrain" compared to elevation values of a DEM derived from the final LiDAR points classified as bare earth. Differences in elevations are calculated to determine a RSME. The RMSE value is multiplied by 1.96 to establish the FVA.

The vertical accuracy is 0.172 feet (5.26 cm) RMSE calculated by comparison of open terrain survey points to DEM elevations. FVA tested 0.338 feet (10.30 cm) vertical accuracy at 95-percent confidence level. The vertical accuracy meets the requirement of RMSE less than 9.25 cm and of a FVA less than 18.13 cm.

These data files include all data points collected.

No points have been removed or excluded.

The raw point cloud is of good quality and data passes Fundamental Vertical Accuracy specifications.

Data cover the entire area specified for this project.

Data is backed up to cloud storage.

The NOAA Office for Coastal Management (OCM) ingested references to the USGS Entwine Point Tile (EPT) hosted on Amazon Web Services (AWS) into the Digital Coast Data Access Viewer (DAV). The DAV accesses the point cloud as it resides on AWS under the usgs-lidar-public-container.