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To acquire QL2+ lidar detailing surface elevation data, vegetation, and buildings for use in conservation planning design, research, floodplain mapping, dam safety assessment and elevation modeling, ect. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEMs. The purpose of this lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 2 US survey feet cell size. These lidar point cloud data were used to create intensity images, 3D breaklines, and hydro-flattened DEMs as necessary. |
| summary:
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To acquire QL2+ lidar detailing surface elevation data, vegetation, and buildings for use in conservation planning design, research, floodplain mapping, dam safety assessment and elevation modeling, ect. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create Intensity Images, Breaklines and Raster DEMs. The purpose of this lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 2 US survey feet cell size. These lidar point cloud data were used to create intensity images, 3D breaklines, and hydro-flattened DEMs as necessary. |
| accessInformation:
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USGS, NRCS, Aerial Services, Inc. |
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| typeKeywords:
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["Data","Service","Image Service","ArcGIS Server"] |
| description:
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<DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>Product: These lidar data are processed Classified LAS 1.4 files, formatted to 7509 individual 2000 US survey feet x 2000 US survey feet tiles; used to create intensity images, 3D breaklines and hydro-flattened DEMs as necessary. Geographic Extent: Champaign County Illinois, covering approximately 1049 square miles. Dataset Description: Champaign County Illinois 2019 Lidar project Description: Block B Champaign County, Illinois 2019 Lidar project called for the planning, acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing of 0.5 meter. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.3. The data was developed based on a horizontal projection/datum of NAD83(2011), State Plane Coordinat System Illinois East (FIPS 1201), United States Survey Feet, and a vertical datum of NAVD88 (GEOID12B), US survey feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 7509 individual 2000 US survey feet x 2000 US survey feet tiles, as was tiled Intensity Imagery, and tiled bare earth DEMs; all tiled to the same 2000 US survey feet x 2000 US survey feet schema. Project called for the planning, acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.5 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.3; Quality Level 2+. The data was developed based on a horizontal projection/datum of NAD83(2011), State Plane Coordinat System Illinois East (FIPS 1201), US survey feet, and a vertical datum of NAVD88 (GEOID12B), US survey feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 7509 individual 2000 US survey feet x 2000 US survey feet tiles, as tiled Intensity Imagery, and as tiled bare earth DEMs; all tiled to the same 2000 x 2000 US survey feet schema. Ground Conditions: Lidar was collected in late 2019 and early 2020, 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, Subcontractor, Surveying and Mapping, LLC (SAM) established a total of 34 ground control points that were used to calibrate the lidar to known ground locations established throughout the Champaign County, Illinois project area. An additional 112 independent accuracy checkpoints, 64 in Bare Earth and Uraban landcovers (64 NVA points), 48 in tall Grass/tall weeds/crops, Brush lands/short trees, Forested categories (48 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data.</SPAN></P></DIV></DIV></DIV> |
| licenseInfo:
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<DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>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.</SPAN></P></DIV></DIV></DIV> |
| catalogPath:
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| title:
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IL_Champaign_DTM_2020 |
| type:
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Image Service |
| url:
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https://isgs-datagis1:6443/arcgis |
| tags:
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["Model","LAS Point Cloud","Remote Sensing","Elevation Data","Lidar"] |
| culture:
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en-US |
| name:
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IL_Champaign_DTM_2020 |
| guid:
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| spatialReference:
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NAD_1983_2011_StatePlane_Illinois_East_FIPS_1201_Ft_US |