Click here to access the data directly from the Illinois State Geospatial Data Clearinghouse.\u00a0
These lidar data are processed Classified LAS 1.4 files,\nformatted to 2,117 individual 2500 ft x 2500 ft tiles; used to create\nReflectance Images, 3D breaklines and hydro-flattened DEMs as necessary.\nGeographic Extent: Lake county, Illinois covering approximately 466 square\nmiles. Dataset Description: WI Kenosha-Racine Counties and IL 4 County QL1\nLidar project called for the Planning, Acquisition, processing and derivative\nproducts of lidar data to be collected at a derived nominal pulse spacing (NPS)\nof 1 point every 0.35 meters. Project specifications are based on the U.S.\nGeological Survey National Geospatial Program Base Lidar Specification, Version\n1.2. The data was developed based on a horizontal projection/datum of NAD83\n(2011), State Plane, U.S Survey Feet and vertical datum of NAVD88 (GEOID12B),\nU.S. Survey Feet. Lidar data was delivered as processed Classified LAS 1.4 files,\nformatted to 2,117 individual 2500 ft x 2500 ft tiles, as tiled Reflectance\nImagery, and as tiled bare earth DEMs; all tiled to the same 2500 ft x 2500 ft\nschema. Ground Conditions: Lidar was collected April-May 2017, while no snow\nwas on the ground and rivers were at or below normal levels. In order to post\nprocess the lidar data to meet task order specifications and meet ASPRS\nvertical accuracy guidelines, Ayers established a total of 66 ground control\npoints that were used to calibrate the lidar to known ground locations\nestablished throughout the WI Kenosha-Racine Counties and IL 4 County QL1\nproject area. An additional 195 independent accuracy checkpoints, 116 in Bare\nEarth and Urban landcovers (116 NVA points), 79 in Tall Grass and Brushland/Low\nTrees categories (79 VVA points), were used to assess the vertical accuracy of\nthe data. These checkpoints were not used to calibrate or post process the\ndata.
\n\nUsers should be aware that temporal changes may have\noccurred since this dataset was collected and that some parts of these data may\nno longer represent actual surface conditions. Users should not use these data\nfor critical applications without a full awareness of its limitations.\nAcknowledgement of the U.S. Geological Survey would be appreciated for products\nderived from these data.
\n\nThese LAS data files include all data points collected. No\npoints have been removed or excluded. A visual qualitative assessment was\nperformed to ensure data completeness. No void areas or missing data exist. The\nraw point cloud is of good quality and data passes Non-Vegetated Vertical\nAccuracy specifications.
Link Source: Illinois Geospatial Data Clearinghouse\u00a0
", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://data-lakecountyil.opendata.arcgis.com/documents/lakecountyil::2017-countywide-lidar-point-cloud", "format": "Web Page", "mediaType": "text/html", "title": "ArcGIS Hub Dataset"}, {"@type": "dcat:Distribution", "accessURL": "https://clearinghouse.isgs.illinois.edu/node/1654", "format": "ArcGIS GeoServices REST API", "mediaType": "application/json", "title": "ArcGIS GeoService"}], "identifier": "https://www.arcgis.com/home/item.html?id=48abf909942840319f9c60926a411597", "issued": "2021-01-12T18:22:54.000Z", "keyword": ["Topography", "Contours", "LiDAR Breaklines", "LiDAR Point Cloud", "Elevation", "Lake County Illinois", "DEM", "Digital elevation model", "2017 Digital Elevation Model", "2017 Lidar"], "landingPage": "https://data-lakecountyil.opendata.arcgis.com/documents/lakecountyil::2017-countywide-lidar-point-cloud", "license": "https://www.arcgis.com/sharing/rest/content/items/89679671cfa64832ac2399a0ef52e414/data", "modified": "2022-03-23T20:20:29.000Z", "publisher": {"name": "Lake County Illinois GIS"}, "spatial": "-88.2150,42.1580,-87.7810,42.4930", "theme": ["geospatial"], "title": "2017 Countywide LiDAR Point Cloud"}