2014 - 2015 USGS Lidar: Clinton, Essex, Lake Champlain, NY

Geographic Extent: Clinton-Essex-Lake Champlain New York, covering approximately 2,699 square miles. The Base order is 1,951 square miles with the Ausable area of interest covering 289 square miles and Saranac area of interest covering 429 square miles.

Dataset Description: Clinton Essex New York 2015 LiDAR project called for the Planning, Acquisition, processing and derivative products of LIDAR data to be collected at a nominal pulse spacing (NPS) of 0.7 meter. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base LIDAR Specification, Version 1.0. The data was developed based on a horizontal projection/datum of UTM Zone 18 North, NAD83, meters and vertical datum of NAVD1988 (GEOID12A), meters. LiDAR data was delivered in RAW flight line swath format, processed to create Classified LAS 1.2 Files formatted to 3,266 individual 1500 meter X 1500 meter tiles, corresponding Intensity Images and Bare Earth DEMs tiled to the same 1500 meter X 1500 meter tile schema, and Breaklines in Esri geodatabase format.

Ground Conditions: LiDAR was collected in Fall 2014/Spring 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 104 Land Cover control points that were used to calibrate the LIDAR to known ground locations established throughout the Clinton-Essex-Lake Champlain project area.

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.

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, contours, hydro-flattened DEMs as necessary.

USGS Contract No. G10PC00026

CONTRACTOR: Quantum Spatial

Ground Control Points were acquired and calibrated by Quantum Spatial

LiDAR data was acquired by both Quantum Spatial and Kucera

Calibration and follow-on processing were completed by Quantum Spatial

The following are the USGS lidar fields in JSON:

{

"ldrinfo" : {

"ldrspec" : "USGS-NGP Base Lidar Specification v1.0",

"ldrsens" : "Leica ALS 70",

"ldrmaxnr" : "4",

"ldrnps" : "0.67",

"ldrdens" : "2.03",

"ldrfltht" : "1859",

"ldrfltsp" : "105",

"ldrscana" : "20.0",

"ldrscanr" : "27.3",

"ldrpulsr" : "153.8",

"ldrpulsd" : "4",

"ldrpulsw" : "0.40",

"ldrwavel" : "1064",

"ldrmpia" : "0",

"ldrbmdiv" : "0.22",

"ldrswatw" : "1292.09",

"ldrswato" : "37.46",

"ldrcrs" : "NAD_1983_UTM_Zone_18N",

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

},

"ldrinfoAdirondak" : {

"ldrspec" : "USGS-NGP Base Lidar Specification v1.0",

"ldrsens" : "Leica ALS 70",

"ldrmaxnr" : "4",

"ldrnps" : "0.62",

"ldrdens" : "2.30",

"ldrfltht" : "2310",

"ldrfltsp" : "160",

"ldrscana" : "14.0",

"ldrscanr" : "52.2",

"ldrpulsr" : "243.2",

"ldrpulsd" : "4",

"ldrpulsw" : "0.53",

"ldrwavel" : "1064",

"ldrmpia" : "1",

"ldrbmdiv" : "0.22",

"ldrswatw" : "1151.90",

"ldrswato" : "21.34",

"ldrcrs" : "NAD_1983_UTM_Zone_18N",

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

},

"ldrinfoPBG" : {

"ldrspec" : "USGS-NGP Base Lidar Specification v1.0",

"ldrsens" : "Leica ALS 70",

"ldrmaxnr" : "4",

"ldrnps" : "0.63",

"ldrdens" : "1.60",

"ldrfltht" : "3090",

"ldrfltsp" : "150",

"ldrscana" : "20.0",

"ldrscanr" : "34.6",

"ldrpulsr" : "193.4",

"ldrpulsd" : "4",

"ldrpulsw" : "0.32",

"ldrwavel" : "1064",

"ldrmpia" : "0",

"ldrbmdiv" : "0.22",

"ldrswatw" : "1002.13",

"ldrswato" : "29.41",

"ldrcrs" : "NAD_1983_UTM_Zone_18N",

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

},

"ldrinfoBTV" : {

"ldrspec" : "USGS-NGP Base Lidar Specification v1.0",

"ldrsens" : "Leica ALS 70",

"ldrmaxnr" : "4",

"ldrnps" : "0.63",

"ldrdens" : "2.26",

"ldrfltht" : "1098",

"ldrfltsp" : "150",

"ldrscana" : "20.0",

"ldrscanr" : "41.0",

"ldrpulsr" : "193.4",

"ldrpulsd" : "4",

"ldrpulsw" : "0.32",

"ldrwavel" : "1064",

"ldrmpia" : "0",

"ldrbmdiv" : "0.22",

"ldrswatw" : "1002.00",

"ldrswato" : "27.90",

"ldrcrs" : "NAD_1983_UTM_Zone_18N",

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

},

"ldrinfo4B6" : {

"ldrspec" : "USGS-NGP Base Lidar Specification v1.0",

"ldrsens" : "Leica ALS 70",

"ldrmaxnr" : "4",

"ldrnps" : "0.62",

"ldrdens" : "2.32",

"ldrfltht" : "1038",

"ldrfltsp" : "150",

"ldrscana" : "19.5",

"ldrscanr" : "41.5",

"ldrpulsr" : "194.0",

"ldrpulsd" : "4",

"ldrpulsw" : "0.32",

"ldrwavel" : "1064",

"ldrmpia" : "0",

"ldrbmdiv" : "0.22",

"ldrswatw" : "974.88",

"ldrswato" : "32.38",

"ldrcrs" : "NAD_1983_UTM_Zone_18N",

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

},

"ldraccur" : {

"ldrchacc" : "-9999",

"rawfva" : "0.129",

"clsfva" : "0.114",

"clscva" : "0.228",

"clssvas" : {

"svalctyp" : "High Grass, Weeds, and Crops",

"svavalue" : "0.266"

},

"clssvas" : {

"svalctyp" : "Forested",

"svavalue" : "0.140"

},

"clssvas" : {

"svalctyp" : "Swamp/Wetland",

"svavalue" : "0.315"

}

},

"lasinfo" : {

"lasver" : "1.2",

"lasprf" : "1",

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

"lasolap" : "Swath "overage" points were identified in these files by adding 128 to the standard classification values.",

"lasintr" : "8",

"lasclass" : {

"clascode" : "1",

"clasitem" : "Processed, but Unclassified"

},

"lasclass" : {

"clascode" : "2",

"clasitem" : "Bare earth ground"

},

"lasclass" : {

"clascode" : "7",

"clasitem" : "Noise"

},

"lasclass" : {

"clascode" : "9",

"clasitem" : "Water"

},

"lasclass" : {

"clascode" : "10",

"clasitem" : "Ignored Ground"

},

"lasclass" : {

"clascode" : "17",

"clasitem" : "Bridge Decks"

},

"lasclass" : {

"clascode" : "18",

"clasitem" : "High Noise"

},

"lasclass" : {

"clascode" : "25",

"clasitem" : "Overlap Water"

}

}}

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.

MicroStation Version 8; TerraScan Version 15; TerraModeler Version 15; GeoCue Version 2014.1.21.1; ESRI ArcGIS 10.2; Global Mapper 15; ALS Post Processor 2.75 Build #25; Windows 7 Operating System \\psihq_nx3200\Projects\23902_ClintonEssex_NY_USGS\ 659 GB and \\Matrix\LIDAR\23902_NYClintonEssex_LakeChamplain 2.87 TB

The specifications require that only Fundamental Vertical Accuracy (FVA) be computed for raw lidar point cloud swath files.

The vertical accuracy value is the AccuracyZ at 95 percent Confidence Interval in meters.

The Raw FVA was tested using 25 independent survey check points located in open terrain. The survey checkpoints were distributed throughout the project area. The 25 independent check points were surveyed using GPS techniques. 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 FVA was computed to be 0.129 meters (or 6.6 cm RMSE). AccuracyZ has been tested to meet 18.13 cm Fundamental Vertical Accuracy at 95 Percent confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines.

Datasets contain complete coverage of tiles.

No points have been removed or excluded.

A visual qualitative assessment was performed to ensure data completeness.

There are no void areas or missing data. The raw point cloud is of good quality and data passes Fundamental Vertical Accuracy specifications.

Classified LAS files were tested by Quantum Spatial for both vertical and horizontal accuracy. All data is seamless from one tile to the next, no gaps or no data areas.

Data is backed up to tape and to cloud storage.

The NOAA Office for Coastal Management (OCM) ingested references to the USGS Entwine Point Tile (EPT) file 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.