Dewberry 20190305 Lidar point cloud Product: These lidar data are processed Classified LAS 1.4 files, formatted to 5,527 individual 2500 ft x 2500 ft tiles; used to create Reflectance Images, 3D breaklines and hydro-flattened DEMs as necessary. Geographic Extent: Cook county, Illinois covering approximately 1239 square miles. Dataset Description: WI Kenosha-Racine Counties and IL 4 County QL1 Lidar project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a derived nominal pulse spacing (NPS) of 1 point every 0.35 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2. The data was developed based on a horizontal projection/datum of NAD83 (2011), State Plane, U.S Survey Feet and vertical datum of NAVD88 (GEOID12B), U.S. Survey Feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 5,527 individual 2500 ft x 2500 ft tiles, as tiled Reflectance Imagery, and as tiled bare earth DEMs; all tiled to the same 2500 ft x 2500 ft schema. Ground Conditions: Lidar was collected April-May 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, Ayers established a total of 66 ground control points that were used to calibrate the lidar to known ground locations established throughout the WI Kenosha-Racine Counties and IL 4 County QL1 project area. An additional 195 independent accuracy checkpoints, 116 in Bare Earth and Urban landcovers (116 NVA points), 79 in Tall Grass and Brushland/Low Trees categories (79 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v1.2 Harris GmAPD Mapping LiDAR Sensor 1 per detector (4096 detectors 0.5 4 0.35 8 7620 240 15 17.7 50 0.46 0.138 1064 1 0.05 3810 55 National Geodetic Survey (NGS) Geoid12B 0.939 0.189 114 0.101 116 0.104 79 1.4 6 The Withheld bit was not used as it is not applicable to a Geiger-mode sensor. The Overlap bit was not used as it is not applicable to a Geiger-mode sensor. 16 1 Processed, but Unclassified 2 Bare Earth Ground 3 Low Vegetation 4 Medium Vegetation 5 High Vegetation 6 Buildings 7 Low Noise 9 Water 10 Ignored Ground 17 Bridge Decks 18 High Noise 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 Reflectance Images, Breaklines and Raster DEM. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened Digital Elevation Model (DEM) with a 2 foot cell size. These lidar point cloud data were used to create Reflectance Images, 3D breaklines, and hydro-flattened DEMs as necessary. USGS Contract No. G16PC00020 CONTRACTOR: Dewberry SUBCONTRACTOR: Harris Corporation Lidar data were acquired and calibrated by Harris Coporation. All follow-on processing was completed by the prime contractor. 20170416 20170507 ground condition Complete None planned -88.201498 -87.746460 42.507332 42.149198 1020000 1142500 2127500 1997500 None Model LAS Point Cloud Remote Sensing Elevation Data Lidar None Illinois Cook County No restrictions apply to these data. 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. Data covers the entire area specified for this project. 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. 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 (0.64 ft) at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm (0.33 ft) in the “bare earth” and "urban" land cover classes. The NVA was tested with 114 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 (0.64 ft) 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. 0.101 Tested 0.101 meters NVA at a 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA). The NVA of the raw lidar point cloud swath files was calculated against TINs derived from the final calibrated and controlled swath data using 114 independent checkpoints located in Bare Earth and Urban land cover classes. Ayers Associates 20170501 vector digital data and tabular digital data Eau Claire, WI Ayers Associates None N/A/ 1640 Online 20170507 ground condition NEIL_GCP This data source was used (along with airborne GPS/IMU data) to georeference the lidar point cloud data. The boresight for each lift was done individually as the solution may change slightly from lift to lift. The following steps describe the Raw Data Processing and Boresight process: 1) Technicians processed the raw data to LAS format flight lines using the final GPS/IMU solution. This LAS data set was used as source data for boresight. 2) Technicians first used F.L.W. Mapping, Inc. proprietary and commercial software to calculate initial boresight adjustment angles based on sample areas selected in the lift. These areas cover calibration flight lines collected in the lift, cross tie and production flight lines. These areas are well distributed in the lift coverage and cover multiple terrain types that are necessary for boresight angle calculation. The technician then analyzed the results and made any necessary additional adjustment until it is acceptable for the selected areas. 3) Once the boresight angle calculation was completed for the selected areas, the adjusted settings were applied to all of the flight lines of the lift and checked for consistency. The technicians utilized commercial and proprietary software packages to analyze how well flight line overlaps match for the entire lift and adjusted as necessary until the results met the project specifications. 4) Once all lifts were completed with individual boresight adjustment, the technicians checked and corrected the vertical misalignment of all flight lines and also the matching between data and ground truth. The relative accuracy was less than or equal to 7 cm RMSEz within individual swaths and less than or equal to 10 cm RMSEz or within swath overlap (between adjacent swaths). 5) The technicians ran a final vertical accuracy check of the boresighted flight lines against the surveyed check points after the z correction to ensure the requirement of NVA = 19.6 cm 95% Confidence Level (Required Accuracy) was met. Point classification was performed according to USGS Lidar Base Specification 1.4, and breaklines were collected for water features. Bare earth DEMs were exported from the classified point cloud using collected breaklines for hydroflattening. NEIL_GCP 20170507 Harris Corporation Jen Nix mailing and physical

1395 Troutman Blvd.

Palm Bay FL 32905 USA (321) 984 6110 (321) 984 6110 jnix02@harris.com Monday - Friday 8 a.m. to 4 p.m. (Central Time) If unable to reach the contact by telephone, please send an email. You should get a response within 24 hours. LAS Point Classification: The point classification is performed as described below. The bare earth surface is then manually reviewed to ensure correct classification on the Class 2 (Ground) points. After the bare-earth surface is finalized, it is then used to generate all hydro-breaklines through heads-up digitization. All ground (ASPRS Class 2) lidar data inside of the Lake Pond and Double Line Drain hydro flattening breaklines were then classified to water (ASPRS Class 9) using TerraScan macro functionality. A buffer of 0.35 m was also used around each hydro-flattened feature to classify these ground (ASPRS Class 2) points to Ignored ground (ASPRS Class 10). All Lake Pond Island and Double Line Drain Island features were checked to ensure that the ground (ASPRS Class 2) points were reclassified to the correct classification after the automated classification was completed. All overlap data was processed through automated functionality provided by TerraScan to classify the overlapping flight line data to approved classes by USGS. The overlap data was classified using standard LAS overlap bit. These classes were created through automated processes only and were not verified for classification accuracy. Due to software limitations within TerraScan, these classes were used to trip the withheld bit within various software packages. These processes were reviewed and accepted by USGS through numerous conference calls and pilot study areas. All data was manually reviewed and any remaining artifacts removed using functionality provided by TerraScan and TerraModeler. Global Mapper us used as a final check of the bare earth dataset. GeoCue was then used to create the deliverable industry-standard LAS files for both the All Point Cloud Data and the Bare Earth. F.L.W. Mapping, Inc. proprietary software was used to perform final statistical analysis of the classes in the LAS files, on a per tile level to verify final classification metrics and full LAS header information. 20180515 Point Transverse Mercator (State Plane Illinois East FIPS 1201) 0.999975 -88.333333 36.666666 984250.0 0.000000 coordinate pair 0.01 0.01 U.S. Survey Feet North American Datum of 1983 Geodetic Reference System 80 6378137 298.257222101 North American Vertical Datum of 1988 0.01 U.S Survey Feet Explicit elevation coordinate included with horizontal coordinates 20190305 Dewberry mailing and physical

1000 N Ashley Drive, Suite 801

Tampa FL 33602 USA (813)225-1325 FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998