2016 - 2017 FEMA Lidar: Frankin and St. Lawrence Counties and Oneida Sub-Basin, NY

Product: These lidar data are processed classified LAS 1.4 files, formatted to 4,597 (Franklin and St. Lawrence) and1351 (Oneida Sub-Basin) individual 1,500-meter x 1,500-meter tiles; used to create intensity images, 3D breaklines, hydro-flattened DEMs, and contours as necessary.

Geographic Extent: Seven counties in New York. East Zone AOI is Franklin and St. Lawrence Counties, Central Zone AOI is Lewis, Madison, Oneida, Onondaga, and Oswego Counties.

Dataset Description: New York FEMA 2016 QL2 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 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2. Lidar data was delivered as flightline-extent unclassified LAS swaths, as processed classified LAS 1.4 files formatted to 4,597 individual 1,500-meter x 1,500-meter tiles, as tiled intensity imagery, and as tiled bare earth DEMs; all tiled to the same 1,500-meter x 1,500-meter schema. Continuous breaklines were produced in Esri file geodatabase format. Contours with a 1-foot interval were produced in Esri file geodatabase format, tiled to the same 1,500-meter x 1,500-meter schema.

Ground Conditions: Lidar was collected in winter/spring of 2016/2017, 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 and meet ASPRS vertical accuracy guidelines, Quantum Spatial, Inc. established a total of 76 ground control points that were used to calibrate the lidar to known ground locations established throughout the New York East Zone (Franklin and St. Lawrence Counties) project area. An additional 71 independent accuracy checkpoints, 71 in Bare Earth and Urban landcovers (59 NVA points), 59 in Forested, Brushland/Trees, and Tall Weeds/Crops categories (59 VVA points), were used to assess the vertical accuracy of the data. Quantum Spatial, Inc. established a total of 30 ground control points that were used to calibrate the lidar to known ground locations established throughout the New York Central Zone (Lewis, Madison, Oneida, Onondaga, and Oswego Counties) project area. An additional 64 independent accuracy checkpoints, 41 in Bare Earth and Urban landcovers (41NVA points), 23 in Forested, Brushland/Trees, and Tall Weeds/Crops categories (25 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data.

The NOAA Office for Coastal Management (OCM) downloaded the 4597 las files from the New York State GIS site. The data for Frankin and St. Lawrence Counties were downloaded from this URL: ftp://ftp.gis.ny.gov/elevation/LIDAR/FEMA_FranklinStLawrence2016/. The data for the Oneida Sub-Basin area (1351 laz files) were downloaded from the USGS ftp site: ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/USGS_LPC_NY_FEMA_R2_B1_2016_LAS_2018/laz/. The data were processed to the Data Access Viewer (DAV) and https. In addition to these lidar point data, the hydro breaklines and the bare earth Digital Elevation Models (DEM) created from the lidar point data are also available. These data are available for custom download at the link provided in the URL section of this metadata record.

To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create intensity images, breaklines, raster DEMs, and contours. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened digital elevation models (DEMs) with a 1-meter cell size. These raw lidar point cloud data were used to create classified lidar LAS files, intensity images, 3D breaklines, hydro-flattened DEMs, and contours as necessary.

USGS Contract No. G10PC00016 CONTRACTOR: Quantum Spatial, Inc. SUBCONTRACTOR: Aerial Surveys International, LLC, Kucera International, Inc. Lidar data were acquired by Quantum Spatial, Inc., Aerial Surveys International, LLC, and Kucera International, Inc. All follow-on processing was completed by the prime contractor.

The following are the USGS lidar fields in JSON:

{

"ldrinfo" : {

"ldrspec" : "USGS-NGP Base Specification v1.2",

"ldrsens" : "Leica ALS 70 HP",

"ldrmaxnr" : "Unlimited",

"ldrnps" : "0.61",

"ldrdens" : "2.67",

"ldranps" : "0.61",

"ldradens" : "2.67",

"ldrfltht" : "2100",

"ldrfltsp" : "140",

"ldrscana" : "38",

"ldrscanr" : "56",

"ldrpulsr" : "262.6",

"ldrpulsd" : "9",

"ldrpulsw" : "8",

"ldrwavel" : "1064",

"ldrmpia" : "1",

"ldrbmdiv" : "0.22",

"ldrswatw" : "1364.66",

"ldrswato" : "30",

"ldrgeoid" : "GEOID12B",

"ldrcrs" : "NAD 1983 (2011) State Plane New York East Zone Meters"

},

"ldrinfo_Riegl" : {

"ldrspec" : "USGS-NGP Base Specification v1.2",

"ldrsens" : "Riegl VQ 1560i",

"ldrmaxnr" : "5",

"ldrnps" : "0.72",

"ldrdens" : "3.16",

"ldranps" : "0.72",

"ldradens" : "3.16",

"ldrfltht" : "5,300",

"ldrfltsp" : "160",

"ldrscana" : "58",

"ldrscanr" : "Variable",

"ldrpulsr" : "700",

"ldrpulsd" : "3",

"ldrpulsw" : "1.00",

"ldrwavel" : "965",

"ldrmpia" : "1",

"ldrbmdiv" : "0.25",

"ldrswatw" : "1795",

"ldrswato" : "30",

"ldrgeoid" : "GEOID12B",

"ldrcrs" : "NAD 1983 (2011) State Plane New York East Zone Meters"

},

"ldraccur" : {

"ldrchacc" : "0",

"rawnva" : "0.0864",

"rawnvan" : "71"

},

"lasinfo" : {

"lasver" : "1.4",

"lasprf" : "6",

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

"lasolap" : "Swath "overage" points were identified in these files using the standard LAS overlap bit",

"lasintr" : "16",

"lasclass" : {

"clascode" : "1",

"clasitem" : "Processed, but Unclassified"

},

"lasclass" : {

"clascode" : "2",

"clasitem" : "Bare-Earth Ground"

},

"lasclass" : {

"clascode" : "7",

"clasitem" : "Low Noise"

},

"lasclass" : {

"clascode" : "9",

"clasitem" : "In-land Water"

},

"lasclass" : {

"clascode" : "10",

"clasitem" : "Ignored Ground"

},

"lasclass" : {

"clascode" : "17",

"clasitem" : "Bridge Decks"

},

"lasclass" : {

"clascode" : "18",

"clasitem" : "High Noise"

}

}}

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.

East Zone (Franklin and St. Lawrence Counties)

The project specifications require that only Non-Vegetated Vertical Accuracy (NVA) be computed for raw lidar point cloud swath files. The required accuracy (ACCz) is: 19.6 cm at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm in the "bare earth" and "urban" land cover classes.

The NVA was tested with 71 checkpoints located in bare earth and urban (non-vegetated) areas. These check points were not used in the calibration or post processing of the lidar point cloud data. The checkpoints were distributed throughout the project area and were surveyed using GPS techniques. See survey report for additional survey methodologies. 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 points. AccuracyZ has been tested to meet 19.6 cm or better Non-Vegetated Vertical Accuracy at 95% 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. The NVA of the raw lidar point cloud swath files was calculated against TINs derived from the final calibrated and controlled swath data using 71 independent checkpoints located in Bare Earth and Urban land cover classes.

Tested 0.0864 meters NVA at a 95% confidence level (4.41 cm NVA RMSE) using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA).

Central Zone (Lewis, Madison, Oneida, Onondaga, Oswego Counties)

The project specifications require that only Non-Vegetated Vertical Accuracy (NVA) be computed for raw lidar point cloud swath files. The required accuracy (ACCz) is: 19.6 cm at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm in the "bare earth" and "urban" land cover classes.

The NVA was tested with 41 checkpoints located in bare earth and urban (non-vegetated) areas. These check points were not used in the calibration or post processing of the lidar point cloud data. The checkpoints were distributed throughout the project area and were surveyed using GPS techniques. See survey report for additional survey methodologies. 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 points. AccuracyZ has been tested to meet 19.6 cm or better Non-Vegetated Vertical Accuracy at 95% 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. The NVA of the raw lidar point cloud swath files was calculated against TINs derived from the final calibrated and controlled swath data using 41 independent checkpoints located in Bare Earth and Urban land cover classes.

Tested 0.1044 meters NVA at a 95% confidence level (5.33 cm NVA RMSE) using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA).

All files are inspected to ensure that they conform to the specified file naming conventions, all files load in their correct geographic position, all files conform to the project specifications for file standard and content. These 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 Non-Vegetated Vertical Accuracy specifications.

Data covers the entire area specified for this project.

Data is backed up to tape and to cloud storage.

Data were collected and processed by Quantum Spatial, Inc. for FEMA. The data were downloaded from the New York State GIS ftp site and the USGS ftp site by the NOAA Office for Coastal Management (OCM) where the data were processed to make it available for custom download from the Data Access Viewer (DAV) and bulk download from https.