5-Appendix I Metadata for Sample Feature Class.txt

Identification_Information:

Citation:

Citation_Information:

Originator: Cook County Government Bureau of Technology, Geographic Information Systems (GIS) Division Publication_Date: 20230426 Title: Cook County 2022 Classified las Geospatial_Data_Presentation_Form: las data Description:

Abstract: LIDAR-derived binary (.las) files containing classified points of all returns. We have eighteen (18) classifications: Unclassified, Ground, Low Veg (0.5-5ft), Medium Veg (5-20ft), High Veg (>20ft), Building, Low Noise, Water, Rail, Road Surface, Wire-Guard (Shield), Wire-Conductor (Phase), Transmission Tower, Wire-Structure Connector, Bridge Decks, High Noise, Overhead Structure and Ignore Ground. Unless otherwise stated, the lidar mapping requirements and deliverables will meet the Quality Level One (QL1) standards as outlined in the USGS NGP Lidar Base Specification 2021, Revision A. The increased lidar density requirement for this project will be met by achieving an Aggregate Nominal Point Density (ANPD) of greater than or equal to 20 points per square meter (>20ppsm), or less than or equal to twenty-two centimeters (<0.22m) Aggregate Nominal Point Spacing (ANPS). Tile sizes are 2500ft x 2500ft.

Purpose:

This task is for providing a spring 2022 leaf-off and snow-free high-density lidar survey over an Area of Interest (AOI) of approximately 1,199 square miles covering Cook County, Illinois (and its surrounds). Derivative products include Digital Terrain Model (DTM), Digital Surface Model (DSM), and one-foot contours. Lidar data captured through this project will be the basis for the creation, update and capture of other separately remotely sensed planimetric data including updates to roads, 3D buildings and footprints, tree inventory, hydrographic features and to provide an accurate Digital Terrain Model (DTM) for annually captured orthoimagery. The County intends to use this data for change detection from previous mission data for assessment purposes and to ensure adherence to building code enforcement. Its uses also include, ecology management, engineering, urban planning and transportation studies, watershed delineation and to provide improved flood and disaster modeling and mitigation efforts.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20220405 Ending_Date: 20220629 Currentness_Reference: ground condition Status:

Progress: Complete Maintenance_and_Update_Frequency: Unknown Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -88.293792697899 East_Bounding_Coordinate: -87.4974076898388 North_Bounding_Coordinate: 42.1780983106989 South_Bounding_Coordinate: 41.441394670546 Keywords:

Theme:

Theme_Keyword_Thesaurus: None Theme_Keyword: Breaklines Theme_Keyword: Elevation Data Theme_Keyword: Lidar Theme_Keyword: DSM Theme_Keyword: Intensity Place:

Place_Keyword_Thesaurus: None Place_Keyword: Cook County, Illinois Access_Constraints: No restrictions apply to these data.

Use_Constraints: None.

Data_Quality_Information:

Logical_Consistency_Report: Data covers the entire area specified for this project.

Completeness_Report: 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.

Positional_Accuracy:

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report:

Vertical (absolute) accuracy of the lidar data will meet AccuracyZ = 0.6ft (18.2cm) at 95% confidence (RMSEZ = 0.3ft [9.25cm]) in accordance with the National Standard for Spatial Data Accuracy (FGDC-STD-007.3-1998) when tested against an independent source of higher accuracy using a minimum of twenty (20) checkpoints that fall within well-defined open terrain.

Lineage:

Process_Step:

Process_Description: Lidar data was collected using Optech Galaxy Prime sensor. The raw data was verified in MARS software for complete coverage of the project area, and boresighted to align the flightlines. Raw data files were parsed into manageable client-specific tiles. These tiles were then processed through automated filtering that separates the data into different classification groups: unclassified points, ground points, low veg, medium veg, high veg, building, low noise, low noise, water, rail, road surface, wire-guard, wire-conductor, transmission tower, wire-structure connector, bridge decks, high noise, overhead structure and ignore ground. The data was next taken into MARS to reclassify the erroneous points that may remain in the lidar point cloud after auto filter. Twenty points per square meter.

Process_Date: 20230426 Process_Contact:

Contact_Information:

Contact_Organization: Cook County Government Bureau of Technology, Geographic Information Systems (GIS) Division Contact_Address:

Address_Type: mailing and physical address Address: 161 North Clark Street, Suite 500 City: Chicago State_or_Province: IL Postal_Code: 60601 Contact_Electronic_Mail_Address: gis@cookcountyil.gov Process_Step:

Process_Description: LiDAR swath data was measured to have an average of 0.224 meter nominal pulse spacing and 20.0 pulses per meter. The method used was counting first return points within each swath, then dividing by the area of the extent of the corresponding swath to get density. NPS was mathematically derived from this density number. This was performed on each swath then averaged to generate the two numbers above. This USGS method does not consider swath sidelap in these calculations.

Process_Date: 20230426 Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Organization: Cook County Government Bureau of Technology, Geographic Information Systems (GIS) Division Contact_Address:

Address_Type: mailing and physical address Address: 161 North Clark Street, Suite 500 City: Chicago State_or_Province: IL Postal_Code: 60601 Contact_Electronic_Mail_Address: gis@cookcountyil.gov Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Point Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Map_Projection:

Map_Projection_Name: NAD 1983 2011 StatePlane Illinois East FIPS 1201 Ft US Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.999975 Longitude_of_Central_Meridian: -88.33333333333333 Latitude_of_Projection_Origin: 36.66666666666666 False_Easting: 984250.0 False_Northing: 0.0 Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation:

Abscissa_Resolution: 0.000000007286249381621703 Ordinate_Resolution: 0.000000007286249381621703 Planar_Distance_Units: foot_us Geodetic_Model:

Horizontal_Datum_Name: D NAD 1983 2011 Ellipsoid_Name: GRS 1980 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257222101 Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988 Geoid2018 Altitude_Resolution: 0.001 Altitude_Distance_Units: feet Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Metadata_Reference_Information:

Metadata_Date: 20230426 Metadata_Contact:

Contact_Information:

Contact_Organization: Cook County Government Bureau of Technology, Geographic Information Systems (GIS) Division Contact_Address:

Address_Type: mailing and physical address Address: 161 North Clark Street, Suite 500 City: Chicago State_or_Province: IL Postal_Code: 60601 Country: USA Contact_Electronic_Mail_Address: gis@cookcountyil.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998