The Public Land Survey System (PLSS) is the way land in the United States is subdivided, it forms the foundation of Cook County's cadastral system for identifying and locating land records. Tax parcels are identified using township and section notation, in a modified format. The PLSS serves as a way for users to navigate the parcel geodatabase. This PLSS feature data set is intended to correspond to tax pages on the Cook County Tax Maps. They should not be used for measurement or surveyor purposes. In addition, the parcel attributes PINA (area/township) and PINSA (subarea/section) do not necessarily correspond to the PLSS township and section polygon in which a given parcel resides. The PLSS data is modeled as a single composite network coverage that encompasses townships (area), sections (subarea), quarter sections, and half quarter section. Tax map pages, which typically correspond to half quarter sections (in an east-west split), are modeled as a region subclass in the LANDFABRIC layer. If an indigenous people's reserve was present on the tax map, it was digitized to create subpolygons of the half-quarter section, and those polygons were attributed with the name of the reserve. Within this PLSS data set, a half-quarter section is the smallest polygon unit, except in cases where an Indigenous People's Reserve line is present. The cadastral data for Cook County have previously not been digital nor automated. This project is the initial automation for this information. This database was designed to represent a continuous, non-overlapping spatial database accounting for all land area in Cook County.The PLSS is updated as needed.

This Address Point feature class contains one point for every address in Survey Township 21 (Township 38 N, Range 15 E; see ccgisdata - Survey Township (Area) 2014).

The Public Land Survey System (PLSS) forms the foundation of Cook County's cadastral system for identifying and locating land records. Tax parcels are identified using township and section notation, in a modified format. This PLSS feature data set is intended to correspond to tax pages in the Cook County Assessor's Tax Map book (current as of tax year 2000 for 66% of the County and as of tax year 2001 for the remaining 33% of the County), and should not be used for measurement or surveyor purposes. In addition, the parcel attributes PINA (area/township) and PINSA (subarea/section) do not necessarily correspond to the PLSS township and section polygon in which a given parcel resides. The PLSS data is modeled as a single composite network coverage that encompasses townships (area), sections (subarea), quarter sections, and half quarter section.

Cook County, Illinois Department of Transportation and Highways expanded GIS data for highway road assets including striping, curbs, raised medians, linear reference system (LRS), mile markers, mileposts, traffic signals, construction projects, bridges and survey monumentation.

This Address Point feature class contains one point for every address in Survey Township 04 (Township 42 N, Range 12 E; see ccgisdata - Survey Township (Area) 2014).

This Address Point feature class contains one point for every address in Survey Township 31 (Township 35 N, Range 13 E; see ccgisdata - Survey Township (Area) 2014).

This data set includes property locations and attached spatial data for all Cook County parcels. Spatial matching was based on parcel centroids. Older properties may be missing latitude and longitude data because they are not contained in the most recent parcel shape layer. Brand new properties may be missing a mailing/property address because the postal service has not yet assigned the property an address. Data attached to each PIN is the most recent available. For example, Census tract data is drawn from the 2014-2018 5-year American Community Survey. The code and sources used to construct this data can be located on GitLab. See data notes for link.

2017 Cook County 1 ft. elevation contours for PLSS Township Area 08. Data is derived from 2017 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets.Details about creating the one foot contours:The contours were processed by the Cook County GIS Department in order to add contour classifications as Index Contours (every 5 feet), Intermediate Contours (every 1 foot), Index Depression Contours, and Intermediate Depression Contours. To create the classification Cook County GIS used the Identify Contour tool in ArcPro. The input was the contour feature and the 2017 DEM that was delivered along with the LiDAR data. Details about the LiDAR Acquisition: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 15,414 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 dataDetails about the DEM: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 raw lidar point cloud data were used to create classified lidar LAS files, Reflectance Images, 3D breaklines, 1 foot contours, and hydro-flattened DEMs as necessary.

This Address Point feature class contains one point for every address in Survey Township 17 (Township 39 N, Range 14 E; see ccgisdata - Survey Township (Area) 2014).

The following dataset includes "Active Benchmarks," which are provided to facilitate the identification of City-managed standard benchmarks. Standard benchmarks are for public and private use in establishing a point in space. Note: The benchmarks are referenced to the Chicago City Datum = 0.00, (CCD = 579.88 feet above mean tide New York). The City of Chicago Department of Water Management’s (DWM) Topographic Benchmark is the source of the benchmark information contained in this online database. The information contained in the index card system was compiled by scanning the original cards, then transcribing some of this information to prepare a table and map. Over time, the DWM will contract services to field verify the data and update the index card system and this online database.This dataset was last updated September 2011. Coordinates are estimated. To view map, go to https://data.cityofchicago.org/Buildings/Elevation-Benchmarks-Map/kmt9-pg57 or for PDF map, go to http://cityofchicago.org/content/dam/city/depts/water/supp_info/Benchmarks/BMMap.pdf. Please read the Terms of Use: http://www.cityofchicago.org/city/en/narr/foia/data_disclaimer.html.

2017 Cook County 1 ft. elevation contours for PLSS Township Area 29. Data is derived from 2017 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets.Details about creating the one foot contours:The contours were processed by the Cook County GIS Department in order to add contour classifications as Index Contours (every 5 feet), Intermediate Contours (every 1 foot), Index Depression Contours, and Intermediate Depression Contours. To create the classification Cook County GIS used the Identify Contour tool in ArcPro. The input was the contour feature and the 2017 DEM that was delivered along with the LiDAR data. Details about the LiDAR Acquisition: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 15,414 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 dataDetails about the DEM: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 raw lidar point cloud data were used to create classified lidar LAS files, Reflectance Images, 3D breaklines, 1 foot contours, and hydro-flattened DEMs as necessary.

This Address Point feature class contains one point for every address in Survey Township 10 (Township 41 N, Range 13 E; see ccgisdata - Survey Township (Area) 2014).

This Address Point feature class contains one point for every address in Survey Township 15 (Township 39 N, Range 12 E; see ccgisdata - Survey Township (Area) 2014).

2017 Cook County 1 ft. elevation contours for PLSS Township Area 11. Data is derived from 2017 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets.Details about creating the one foot contours:The contours were processed by the Cook County GIS Department in order to add contour classifications as Index Contours (every 5 feet), Intermediate Contours (every 1 foot), Index Depression Contours, and Intermediate Depression Contours. To create the classification Cook County GIS used the Identify Contour tool in ArcPro. The input was the contour feature and the 2017 DEM that was delivered along with the LiDAR data. Details about the LiDAR Acquisition: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 15,414 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 dataDetails about the DEM: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 raw lidar point cloud data were used to create classified lidar LAS files, Reflectance Images, 3D breaklines, 1 foot contours, and hydro-flattened DEMs as necessary.

2022 Cook County 1 ft. elevation contours for PLSS Township Area 10 Data is derived from 2022 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets. Abstract: One-foot interval contours are generated from a two-foot two-pass gridded surface created from the ground (class = 2) and road surface (class = 11) classified lidar points and the hydro breaklines. 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).

2017 Cook County 1 ft. elevation contours for PLSS Township Area 22. Data is derived from 2017 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets.Details about creating the one foot contours:The contours were processed by the Cook County GIS Department in order to add contour classifications as Index Contours (every 5 feet), Intermediate Contours (every 1 foot), Index Depression Contours, and Intermediate Depression Contours. To create the classification Cook County GIS used the Identify Contour tool in ArcPro. The input was the contour feature and the 2017 DEM that was delivered along with the LiDAR data. Details about the LiDAR Acquisition: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 15,414 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 dataDetails about the DEM: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 raw lidar point cloud data were used to create classified lidar LAS files, Reflectance Images, 3D breaklines, 1 foot contours, and hydro-flattened DEMs as necessary.

This Address Point feature class contains one point for every address in Survey Township 26 (Township 37 N, Range 15 E; see ccgisdata - Survey Township (Area) 2014).

2017 Cook County 1 ft. elevation contours for PLSS Township Area 16. Data is derived from 2017 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets.Details about creating the one foot contours:The contours were processed by the Cook County GIS Department in order to add contour classifications as Index Contours (every 5 feet), Intermediate Contours (every 1 foot), Index Depression Contours, and Intermediate Depression Contours. To create the classification Cook County GIS used the Identify Contour tool in ArcPro. The input was the contour feature and the 2017 DEM that was delivered along with the LiDAR data. Details about the LiDAR Acquisition: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 15,414 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 dataDetails about the DEM: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 raw lidar point cloud data were used to create classified lidar LAS files, Reflectance Images, 3D breaklines, 1 foot contours, and hydro-flattened DEMs as necessary.

This Address Point feature class contains one point for every address in Survey Township 01 (Township 42 N, Range 9 E; see ccgisdata - Survey Township (Area) 2014).

2022 Cook County 1 ft. elevation contours for PLSS Township Area 20 Data is derived from 2022 lidar. If you plan on downloading this dataset it is recommended to use the File Geodatabase option. The shapefile format may not work for larger datasets. Abstract: One-foot interval contours are generated from a two-foot two-pass gridded surface created from the ground (class = 2) and road surface (class = 11) classified lidar points and the hydro breaklines. 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).