Illinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinois Unpublished Material raster digital data http://www.isgs.illinois.edu Recommended Publishing Citation:llinois Height Modernization Program, Illinois State Geological Survey, and Cook County Board of Commissioners, 2002–2014, Illinois LiDAR county database: Illinois State Geological Survey http://crystal.isgs.uiuc.edu/nsdihome/webdocs/ilhmp/ (accessed September 18, 2014) This Digital Surface Model (DSM) data was produced all or in part from LiDAR information as of 2008. The LiDAR derived DSM covers Cook County, Illinois and include inland streams, rivers, lakes ponds and tidal features. These data are appropriate for use in local and regional analysis. This data set has a vertical accuracy of 9.14 centimeters RMSEz, horizontal accuracy of 0.67 meters and point spacing of 1.0 meters. Digital Elevation Models (including terrain and surface models) are raster data sets created from whole LiDAR point cloud data sets (LAS files). The LAS files are the standard LiDAR file format which contains the raw point cloud data, these data are normally classified and distinguished between points on the ground, water or elevated features such as buildings, trees, towers, bridges, etc.. These LAS files are processed into elevation models to create gridded rasters. The first returns can be used to map the top reflective surface (Digital Surface Models - DSM), these normally include open terrain areas, as well as the tops of buildings, trees, towers, and other features elevated above the bare earth. The last returns are used to map the bare-earth terrain (Digital Terrain Models - DTM), these are normally produced with irregularly-spaced points rather than the uniform grid structure of a Digital Elevation Model (DEM), Digital Terrain Models will often include breaklines to help define edges of water bodies. These acquisitions of the LiDAR data and its derivatives were made possible by a grant from the National Geodetic Survey for the National Height Modernization Program. The program is in place to enable states access to accurate, reliable heights using global positioning satellite (GPS) technology in conjunction with traditional leveling, gravity, and modern remote sensing technologies. LiDAR data and its derivatives assist in real-world uses around the state of Illinois such as; highway engineering, flood prediction, agricultural land management, mining subsidence, monitoring archaeological features, locating sinkholes and applied geologic science. The data do not replace the need for detailed site-specific studies. The information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. The information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. none 20081121 20081123 20081125 20081126 20081128 20081129 20090411 20090412 20090413 20090414 ground condition Complete Unknown -88.2 -87.5 42.1 41.4 None Light Detection and Ranging LiDAR Bare Earth Point Cloud Digital Elevation Model DEM Elevation Surface Model Digital Surface Model DSM Hillshade None US Illinois Department of Transportation Illinois Cook County None 2008 Cook County LiDAR derivatives are proprietary data that belongs to the County of Cook and MUST NOT be distributed without the county's consent. ISGS information must be obtained directly from the ISGS or from an authorized distributor. Be aware that ISGS information obtained from an unauthorized third party may have been altered subsequent to original distribution, or may no longer be current. Any access to these data, Web sites, computer systems, electronic services, and electronic networks is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. Cook County LiDAR derivatives are proprietary data that belongs to the County of Cook and MUST NOT be distributed without the county's consent. ISGS information is the property of and copyrighted by the Board of Trustees of the University of Illinois with all rights reserved. University copyright policy is stated in the General Rules Concerning University Organization and Procedure, Article III, Section 4. A link is provided in the Cross References section. Individuals or entities may make fair use of copyrighted ISGS material, such as reproducing a single figure or table, or using a brief text quotation, without obtaining formal permission, but in all cases the Illinois State Geological Survey must be credited as the source of the material. To reproduce ISGS information beyond the fair use standard, permission must be obtained from the ISGS Information Office, 615 East Peabody Drive, Champaign, Illinois 61820, 217-333-4747, isgs@isgs.illinois.edu. License fees and a license agreement may be required, depending on the proposed usage. Any use of these data is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. Map information is to be used at a scientifically and cartographically appropriate scale, that is, at a scale no greater than indicated on the map or as described in the documentation of the map or map data. Map information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. Map information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. The data do not replace the need for detailed site-specific studies. Merrick & Co., Illinois State Geological Survey, Illinois Department of Transportation, Cook County Board of Commissioners Illinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinois mailing and physical address

615 E. Peabody

Champaign IL 61820 USA 217-333-4747 info@isgs.illinois.edu Monday thru Friday, 8am - 5pm 217-785-0211 http://www.cam.illinois.edu/viii/VIII-1.1.htm http://www.isgs.illinois.edu http://www.vpaa.uillinois.edu/policies/web_privacy.cfm http://www.uillinois.edu/trustees/rules.cfm#sec34 Due to repeated inspection, the accuracy of the attributes in this dataset are assessed to be excellent. Refer also to the Disclaimer of Warranties and Accuracy of Data section of the Legal Notices of Terms and Conditions section of the University of Illinois Web Privacy Policy. A link is provided in the Cross References section. All data have had QAQC visual and statistical testing using observations performed to compare the derivative products (breaklines, classified LAS, DEM and DSM/DTM) as well as aerial photography to check for the logical consistency of the data. Complete The final DTM met or exceeded 0.67056000 meters (2.2 feet) horizontal accuracy at the 95 percent confidence level (Accuracy = RMSEr x 1.7308) 0.67 meters National Standard for Spatial Data Accuracy The final DTM met or exceeded 0.18288000 meters (0.6 feet) vertical accuracy at the 95 percent confidence level in open terrain (Accuracy = RMSEr x 1.9600) 9.14 cm RMSEz National Standard for Spatial Data Accuracy 1) Acquisition of digital elevation data A Light Detection and Ranging (LiDAR) system was used to collect elevation data to develop the Digital Terrain Model (DTM) and the Digital Surface Model (DSM). The LiDAR system used rapidly transmits pulses of light that reflect off the terrain and other height objects. The return pulse is converted from photons to electrical impulses and collected by a high-speed data recorder. Since the formula for the speed of light is well known, time intervals from transmission to collection are derived. Time intervals are then converted to distance based on positional information obtained from ground/aircraft GPS receivers and the on-board Inertial Measurement Unit (IMU) that record the attitude (pitch, roll, and heading) of the aircraft. The LiDAR system collects positional (x,y) and elevation (z) data at pre-defined intervals. The resulting LiDAR data is a dense network of elevation postings. The accuracy of LiDAR data is a function of flying height, laser beam diameter (system dependent), the quality of the GPS/IMU data, and postprocessing procedures. Accuracies better than 7cm (vertically) were achieved from initial testing of Merrick's system. Merrick used a topographic LiDAR mapping system based on the Leica GeoSystems ALS50 platform. The system integrates a laser Altimeter, an Applanix POS/AVIMU Inertial Measurement Unit (IMU), GPS flight management and other sub-systems. This integrated system is capable of 45KHz operation at a 75 degree Field of View (FOV). The system configuration includes extended altitude range up to 4,700m at 75 degrees, target signal intensity capture, and three return capture. The sensor is capable of generating five returns, however, the first three returns generate the maximum collection and Merrick's sensor has been configured to maximize these first three returns. This advanced sensor has the capability to collect terrain data at a swath width of over two miles. The accuracy of laser generated terrain data exceeds 15cm Root Mean Square Error (RMSE), altitude. All airborne GPS reference base stations identified for use in controlling the project were submitted to Cook County for review and approval. Generally, a single base station was required to cover a 25-mile flight radius. For the Cook County project, a minimum of two (2) GPS base stations were utilized for redundancy on any given flight day. The base station points selected were High Accuracy Reference Network (HARN), bluebooked National Geodetic Survey (NGS) control points. Base stations were established on these points before any airborne data were collected, and were tied to the Cook County control network. GPS position data was recorded at one-second intervals, or epochs, throughout the entire mission. All LiDAR flight planning, reporting, and data processing met FEMA specifications/requirements available at: <http://www.fema.gov/library/file?type=publishedFile&file=lidar_4b.pdf&fileid=42a04d30-a0b8-11db-b057-000bdba87d5b> In-flight data was logged to hard drives, which provides for immediate viewing of post mission data. Data quality, coverage, and other mission critical information were reviewed immediately to determine if re-flights are necessary. The basic parameters for Merrick's LiDAR system were as follows: Operating Altitude: 500 to 4,700 meters Elevation accuracy: <15cm RMSE (Alt dependent) Horizontal accuracy: <15cm RMSE (Alt dependent) GPS receiver: Novatel Millennium Laser repetition rate: 100 Hz to 150KHz Scan angle: 5 - 75 degrees Swath width: Variable Scan Frequency: Variable (scan angle dependent) Return Pulse: Up to three (pulse rate dependent) Intensity: Yes (up to three) Full calibration/verification of the LiDAR sensor is verified on a regular basis (monthly) at Jefferson County Airport in Broomfield, Colorado, Merrick's LiDAR Operations facility. The site has over 500 GPS centimeter class accuracy control points, which include runways, taxiways, buildings, rooftops, and other features. Points are both surface and photo identifiable targets. In addition to GPS control, a rigorous photogrammetric solution was obtained utilizing photography flown at a scale 1"=600', which is utilized for stereo surface validation and 6-inch orthophoto reference. Flights were performed over the calibration site across the full dynamic range for altitude; scan rate, and pulse rates from four cardinal directions and encompassed the full swath width of the on-ground scan over the GPS control surface data. Post-processed data was incorporated into Merrick’s proprietary software where cross sectional profiles were measured and analyzed for flight line coherence and flight line ground truth coherence. Additionally, an analysis was performed, which correlates the entire control network to the LiDAR data for adherence to the project map specification. Any project variables which deviated from the normal calibration results were investigated and resolved before final processing of data. Calibration validation was also performed at the project location to assure anomalies had not occurred en route to the site or during data collection. Typically, a limited survey is performed at the local airport to ensure mission performance. Proper calibration also allows errors to be evaluated and adjusted (if necessary) during post-processing and projection of DEM surface data to the project control. The density that the elevations were sampled by LiDAR was 10'. Actual results vary since the density of the mass points will be greater in areas where flight lines overlapped and possibly less in those areas where mass points were removed to accommodate breaklines. The Cook County LiDAR flight plan consisted of a total of 167 flight lines (138 North/South flight lines, 20 dense cross-flights and 9 Central Business District (CBD) cross-flights. This calculates to approximately 3,786 flight miles (3,375 North/South Countywide flight miles, 387 dense cross-flight miles, and 27 CBD cross-flight miles). Cross flights were deemed necessary in order to minimize the problem commonly referred to as shadowing by high relief urban features in the CBD. Flights were flown perpendicular to urban features as was practical in order to minimize this effect and to ensure the preservation of data density throughout the area. Data was then merged to produce a higher density in the narrow alleys between high relief buildings. Additionally, Merrick acquired flight lines that were parallel to Lake Michigan and extended inland from Lake Shore Drive to encompass the "Loop" area. ISGS Secondary Processing: 1. Thorough QAQC check was completed to ensure and evaluate the quality of the data delivered and that all the specifications have been met in accordance to the contract and national specifications set for LiDAR data. 2. Through ArcGIS 10.1 the following steps were completed to created Terrain and hillshade products: a. LAS to Mulitpoint conversion using 3D analyst tools.ASPRS Classifications were used below: 1-Unclassified 2-Ground 3-Low Vegetation 4-Medium Vegetation 5-High Vegetation 6-Building 8-Model Key Points 9-Water b. Terrains are then created and pyramids are calculated. c. Terrain to Raster tool was used in 3D Analyst. The parameters of data type float, natural neighbors method, sampling distance is cell size and the point spaceing value from the LiDAR data. d. Hillshades are created from the above rasters with a Z value of 2. 3. These derivatives were checked again visually for errors. If any errors were perceived corrections were coordinated with vendor and products were updated with corrections. 4. When product was finalized then metadata was completed before making data available. 20090414 Unknown Raster coordinate pair 0.001 0.001 survey feet North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222 NAD_1983_HARN_StatePlane_Illinois_East_FIPS_1201_Feet North American Vertical Datum of 1988 0.01 feet Explicit elevation coordinate included with horizontal coordinates 20140923 Illinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinois mailing and physical address

615 East Peabody Drive

Champaign IL 61820 US 217-333-4747 isgs@isgs.illinois.edu Monday through Friday 8:00 AM to 5:00 PM (Central Time) FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 The access constraints as stated for the data apply also to the metadata. Refer to the Access Constraints section of the Identification Information section. The use constraints as stated for the data apply also to the metadata. Refer to the Use Constraints section of the Identification Information section. 20130301 12273000 FGDC CSDGM Metadata FALSE file://\\ISGS-VOLCANO\lidarproducts\counties\cook\cook_dsm Local Area Network cook_dsm 002 1003131.500774 1205628.500774 1749872.619706 1998827.619706 1 Projected GCS_North_American_1983_HARN Linear Unit: Foot_US (0.304801) NAD_1983_HARN_StatePlane_Illinois_East_FIPS_1201_Feet <ProjectedCoordinateSystem xsi:type='typens:ProjectedCoordinateSystem' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns:xs='http://www.w3.org/2001/XMLSchema' xmlns:typens='http://www.esri.com/schemas/ArcGIS/10.1'><WKT>PROJCS[&quot;NAD_1983_HARN_StatePlane_Illinois_East_FIPS_1201_Feet&quot;,GEOGCS[&quot;GCS_North_American_1983_HARN&quot;,DATUM[&quot;D_North_American_1983_HARN&quot;,SPHEROID[&quot;GRS_1980&quot;,6378137.0,298.257222101]],PRIMEM[&quot;Greenwich&quot;,0.0],UNIT[&quot;Degree&quot;,0.0174532925199433]],PROJECTION[&quot;Transverse_Mercator&quot;],PARAMETER[&quot;False_Easting&quot;,984250.0],PARAMETER[&quot;False_Northing&quot;,0.0],PARAMETER[&quot;Central_Meridian&quot;,-88.33333333333333],PARAMETER[&quot;Scale_Factor&quot;,0.999975],PARAMETER[&quot;Latitude_Of_Origin&quot;,36.66666666666666],UNIT[&quot;Foot_US&quot;,0.3048006096012192],AUTHORITY[&quot;EPSG&quot;,3443]],VERTCS[&quot;NAVD_1988&quot;,VDATUM[&quot;North_American_Vertical_Datum_1988&quot;],PARAMETER[&quot;Vertical_Shift&quot;,0.0],PARAMETER[&quot;Direction&quot;,1.0],UNIT[&quot;Foot_US&quot;,0.3048006096012192]]</WKT><XOrigin>-17463800</XOrigin><YOrigin>-46132600</YOrigin><XYScale>137244822.07846552</XYScale><ZOrigin>-100000</ZOrigin><ZScale>3048.0060960121923</ZScale><MOrigin>-100000</MOrigin><MScale>10000</MScale><XYTolerance>0.0032808333333333331</XYTolerance><ZTolerance>0.0032808333333333331</ZTolerance><MTolerance>0.001</MTolerance><HighPrecision>true</HighPrecision><WKID>3443</WKID><LatestWKID>3443</LatestWKID></ProjectedCoordinateSystem> 32 FALSE None 1 GRID TRUE continuous floating point -3.4028235e+038 20140205 10003700 20160330 14271900 150000000 5000 1.0 FGDC Illinois State Geological Survey (ISGS), a division of the Prairie Research Institute of the University of Illinois mailing and physical address

615 East Peabody Drive

Champaign IL 61820 USA 217-244-2414 isgs@isgs.illinois.edu Refer to the Legal Notices of Terms and Conditions of the University of Illinois Web Privacy Policy (there is a link in the Cross References section) for policy statements regarding the following: Disclaimer of Liability Disclaimer of Warranties and Accuracy of Data Disclaimer of Endorsement Disclaimer for External Links Disclaimer of Duty to Continue Provision of Data Security Choice of Law By obtaining these data you agree to the provisions of the University of Illinois Web Privacy Policy, regardless of the manner in which the information was obtained. other no compression applied http://www.isgs.uiuc.edu/nsdihome/webdocs/ilhmp/ http://www.isgs.uiuc.edu/nsdihome/webdocs/ilhmp/ Windows 7 CD-ROM none no fees The data are intended for use with GIS software. The ISGS uses ESRI ArcGIS software, however, ESRI formats can be imported into many different GIS software packages. It is expected that customers who obtain these data have the technical expertise to use GIS software. The ISGS does not provide software support of any kind. GRID Raster ISGS Raster Grid Values Raster Grid Values ISGS Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.1.1.3143 IL_Cook_DSM_2008 Recommended Publishing Citation: Illinois Height Modernization Program, Illinois State Geological Survey, and Cook County, 2002–2016, Illinois Height Modernization Program (ILHMP): LiDAR data: Illinois State Geological Survey http://clearinghouse.isgs.illinois.edu/ (accessed March 30, 2016) 1 -88.264436 -87.516946 42.154305 41.468283 These acquisitions of the LiDAR data and its derivatives were made possible by a grant from the National Geodetic Survey for the National Height Modernization Program. The program is in place to enable states access to accurate, reliable heights using global positioning satellite (GPS) technology in conjunction with traditional leveling, gravity, and modern remote sensing technologies. LiDAR data and its derivatives assist in real-world uses around the state of Illinois such as; highway engineering, flood prediction, agricultural land management, mining subsidence, monitoring archaeological features, locating sinkholes and applied geologic science. The data do not replace the need for detailed site-specific studies. The information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. The information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. <DIV STYLE="text-align:Left;"><DIV><P><SPAN>This Digital Surface Model (DSM) data was produced all or in part from LiDAR information as of 2008. The LiDAR derived DSM covers Cook County, Illinois and include inland streams, rivers, lakes ponds and tidal features. These data are appropriate for use in local and regional analysis. This data set has a vertical accuracy of 9.14 centimeters RMSEz, horizontal accuracy of 0.67 meters and point spacing of 1.0 meters. Digital Elevation Models (including terrain and surface models) are raster data sets created from whole LiDAR point cloud data sets (LAS files). The LAS files are the standard LiDAR file format which contains the raw point cloud data, these data are normally classified and distinguished between points on the ground, water or elevated features such as buildings, trees, towers, bridges, etc.. These LAS files are processed into elevation models to create gridded rasters. The first returns can be used to map the top reflective surface (Digital Surface Models - DSM), these normally include open terrain areas, as well as the tops of buildings, trees, towers, and other features elevated above the bare earth. The last returns are used to map the bare-earth terrain (Digital Terrain Models - DTM), these are normally produced with irregularly-spaced points rather than the uniform grid structure of a Digital Elevation Model (DEM), Digital Terrain Models will often include breaklines to help define edges of water bodies.</SPAN></P></DIV></DIV> Merrick & Co., Illinois State Geological Survey, Illinois Department of Transportation, Cook County Board of Commissioners Light Detection and Ranging LiDAR Bare Earth Point Cloud Digital Elevation Model DEM Elevation Surface Model Digital Surface Model DSM Hillshade <DIV STYLE="text-align:Left;"><DIV><P><SPAN>Cook County LiDAR derivatives are proprietary data that belongs to the County of Cook and MUST NOT be distributed without the county's consent. ISGS information is the property of and copyrighted by the Board of Trustees of the University of Illinois with all rights reserved. University copyright policy is stated in the General Rules Concerning University Organization and Procedure, Article III, Section 4. A link is provided in the Cross References section. Individuals or entities may make fair use of copyrighted ISGS material, such as reproducing a single figure or table, or using a brief text quotation, without obtaining formal permission, but in all cases the Illinois State Geological Survey must be credited as the source of the material. To reproduce ISGS information beyond the fair use standard, permission must be obtained from the ISGS Information Office, 615 East Peabody Drive, Champaign, Illinois 61820, 217-333-4747, isgs@isgs.illinois.edu. License fees and a license agreement may be required, depending on the proposed usage. Any use of these data is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. Map information is to be used at a scientifically and cartographically appropriate scale, that is, at a scale no greater than indicated on the map or as described in the documentation of the map or map data. Map information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. Map information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. The data do not replace the need for detailed site-specific studies.</SPAN></P></DIV></DIV> Raster Dataset dataset EPSG 7.11.2 2 1 0 1003131.500774 1749872.619706 1003131.500774 1998827.619706 1205628.500774 1998827.619706 1205628.500774 1749872.619706 1104380.000774 1874350.119706 67499 3.000000 82985 3.000000 cook_dsm 3387.458496 34.332344 32 20160330