Product: These lidar data are part of a 8 county project in the NorthWest of Illinois. This data are processed Classified LAS 1.4 files, formatted to 14482 individual 1000 meter x 1000 meter tiles; used to create intensity images, 3D breaklines and hydro-flattened DEMs as necessary. Geographic Extent: Jo Daviess, Stephenson, Carroll, Ogle, Whiteside, Lee, Rock Island, and Henry Counties Illinois, covering approximately 5318 square miles. Dataset Description: Illinois 8 county 2019 Lidar Dataset Description: Block 3_IL_8 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 37,739 individual 2000 US survey feet x 2000 US survey feet tiles, and 37,738 tiled Intensity Imagery, and 37,739 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. Tile 2075_1735 is located within a water body with no reflectance measured within the tile boundary, so no intensity image was produced for that tile. 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 37,739 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 -- ISGS QAQC comments: Almost all of the buildings have been classified as vegetation. These points should be classified as class 1 but was not corrected. There are Erroneous High and Low points found in a North - South swath over the Whiteside and Carroll counties and an East - West strip in Jo Daviess county. There are flight lines that are out of tolerance. -- Ground Conditions: Lidar was collected in late 2019, early 2020 and late 2020 while no snow was on the ground, and rivers levels fluctuated. 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 76 ground control points that were used to calibrate the lidar to known ground locations established throughout the Block 3_IL_8 County project area. An additional 219 independent accuracy checkpoints, 127 in Bare Earth and Uraban landcovers (127 NVA points), 92 in tall Grass/tall weeds/crops, Brush lands/short trees, Forested categories (92 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data.