2019 USGS Lidar: Eldorado CA

The Project data set consists of the Classified Point Cloud. The Geographical Extent of this dataset extends to the entirety of the CA_UpperSouthAmerican_Eldorado_2019_B19 boundary, approximately 2,275 square miles of the AOIs. Ground Conditions: water at normal levels; no unusual inundation; no snow; leaf off. How the Withheld Points are Identified: Withheld (ignore) points were identified in the files using the standard LAS Withheld bit.

The USGS/BLM contracted Digital Aerial Solutions, LLC to obtain professional services related to the planning, acquisition and development of Light Detection and Ranging (Lidar) data and derivative products. The task order is for a QL1 LiDAR survey to be collected over Alameda, Alpine, Amador, Calveras, El Dorado, Placer, Sacramento, San Joaquin, Santa Clara and Stanislaus counties in California.

This metadata 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.

The deliverable products would be used by the USGS/BLM for conservation planning, design, research, floodplain mapping, wetlands identification, dam safety assessments, hydrologic modeling, and other environmental purposes.

All Lidar data and associated products were acquired, calibrated, and used in the creation of Lidar derived products by Digital Aerial Solutions, LLC.

ANPS: 0.35 Meters

Tile Size: 2,500 Feet

Spec: National Geospatial Program(NGP) Lidar Base Specification v2.1

LAS File Type: 1.4 type 6

The following are the USGS lidar fields in JSON:

{

"ldrinfo" : {

"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program(NGP) Lidar Base Specification v2.1",

"ldrsens" : "Leica Terrian Mapper SN# 90524",

"ldrmaxnr" : "15",

"ldrnps" : "0.35",

"ldrdens" : "8.11",

"ldranps" : "0.35",

"ldradens" : "8.11",

"ldrfltht" : "1900",

"ldrfltsp" : "170",

"ldrscana" : "40.0",

"ldrscanr" : "150.0",

"ldrpulsr" : "1,540",

"ldrpulsd" : "3.3",

"ldrpulsw" : "0.45",

"ldrwavel" : "1064",

"ldrmpia" : "0",

"ldrbmdiv" : "0.25",

"ldrswatw" : "13383.09",

"ldrswato" : "30-55",

"ldrgeoid" : "National Geodetic Survey (NGS) Geoid 12B"

},

"ldraccur" : {

"ldrchacc" : "0",

"rawnva" : "0",

"rawnvan" : "0",

"clsnva" : "0",

"clsnvan" : "0",

"clsvva" : "0",

"clsvvan" : "0"

},

"lasinfo" : {

"lasver" : "1.4",

"lasprf" : "6",

"laswheld" : "Withheld (ignore) points were identified in the 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" : "Undetermined/Unclassified"

},

"lasclass" : {

"clascode" : "2",

"clasitem" : "Bare earth"

},

"lasclass" : {

"clascode" : "7",

"clasitem" : "Low Noise"

},

"lasclass" : {

"clascode" : "9",

"clasitem" : "Water"

},

"lasclass" : {

"clascode" : "17",

"clasitem" : "Bridges"

},

"lasclass" : {

"clascode" : "18",

"clasitem" : "High Noise"

},

"lasclass" : {

"clascode" : "20",

"clasitem" : "Ignored Ground"

},

"lasclass" : {

"clascode" : "21",

"clasitem" : "Snow"

},

"lasclass" : {

"clascode" : "22",

"clasitem" : "Temporal Exclusion"

}

}}

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None, 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.

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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.

Inertial Explorer ver: 8.9; Leica HxMap Ver:2.5.1; GeoCue Ver: 2014.1.21.4; Microstation V8i; Terresolid ver: 2015; LP360 ver: 2014.1.51.1; Arcmap ver: 10.4; Global Mapper ver: 16

This data set was produced to meet ASPRS Positional Accuracy Standard for Digital Geospatial Data (2014) for a 10-cm RMSEz Vertical Accuracy Class.

USGS Determined Vertical Accuracy

Non-Vegetated Vertical Accuracy (NVA) = 5.6 cm RMSE

Vegetated Vertical Accuracy (VVA) = 21.94 cm at the 95th Percentile

Please refer to the USGS Work Package report in the URL section of this metadata record for additional information about the vertical accuracy determinations.

The RAW LAS data files included 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 Fundamental Vertical Accuracy specifications. Void areas (i.e., areas outside the project boundary but within the tiling scheme) are coded using a unique NODATA value. This value is identified in the appropriate location within the file header.

Aerial LiDAR data covers the entire 2,275 square mile Area of Interest intended for this project task. All LiDAR Point Cloud tiles show no edge artifacts or mismatches from tile to tile. Void areas (i.e., areas outside the project boundary but within the tiling scheme) are coded using a unique NODATA value. This value is identified in the appropriate location within the file header. Data cover the entire area specified for this project.

Data is backed up to tape and to cloud storage.

The CA Eldorado lidar was ingested into the Data Access Viewer for custom product generation by leveraging USGS hosted Entwine Point Tiles.