This dataset contains the historical estimated congestion for over 1,000 traffic segments, starting in approximately March 2018. Older records are in https://data.cityofchicago.org/d/77hq-huss. The most recent estimates for each segment are in https://data.cityofchicago.org/d/n4j6-wkkf.

The Chicago Traffic Tracker estimates traffic congestion on Chicago’s arterial streets (non-freeway streets) in real-time by continuously monitoring and analyzing GPS traces received from Chicago Transit Authority (CTA) buses. Two types of congestion estimates are produced every 10 minutes: 1) by Traffic Segments and 2) by Traffic Regions or Zones. Congestion estimates by traffic segments gives observed speed typically for one-half mile of a street in one direction of traffic. Traffic Segment level congestion is available for about 300 miles of principal arterials.

Congestion by Traffic Region gives the average traffic condition for all arterial street segments within a region. A traffic region is comprised of two or three community areas with comparable traffic patterns. 29 regions are created to cover the entire city (except O’Hare airport area). There is much volatility in traffic segment speed. However, the congestion estimates for the traffic regions remain consistent for a relatively longer period. Most volatility in arterial speed comes from the very nature of the arterials themselves. Due to a myriad of factors, including but not limited to frequent intersections, traffic signals, transit movements, availability of alternative routes, crashes, short length of the segments, etc. Speed on individual arterial segments can fluctuate from heavily congested to no congestion and back in a few minutes.

The segment speed and traffic region congestion estimates together may give a better understanding of the actual traffic conditions.

The Chicago Park District issues swim advisories at beaches along Chicago's Lake Michigan lakefront based on E. coli levels. This dataset shows predicted E. coli levels based on an experimental analytical modeling approach.

This dataset contains the current estimated congestion for the 29 traffic regions. For a detailed description, go to: http://bitly.com/TeqrNv.

The Chicago Traffic Tracker estimates traffic congestion on Chicago’s arterial streets (non-freeway streets) in real-time by continuously monitoring and analyzing GPS traces received from Chicago Transit Authority (CTA) buses. Two types of congestion estimates are produced every 10 minutes: 1) by Traffic Segments and 2) by Traffic Regions or Zones. Congestion estimates by traffic segments gives observed speed typically for one-half mile of a street in one direction of traffic. Traffic Segment level congestion is available for about 300 miles of principal arterials. Congestion by Traffic Region gives the average traffic condition for all arterial street segments within a region. A traffic region is comprised of two or three community areas with comparable traffic patterns. 29 regions are created to cover the entire city (except O’Hare airport area).

There is much volatility in traffic segment speed. However, the congestion estimates for the traffic regions remain consistent for a relatively longer period. Most volatility in arterial speed comes from the very nature of the arterials themselves. Due to a myriad of factors, including but not limited to frequent intersections, traffic signals, transit movements, availability of alternative routes, crashes, short length of the segments, etc. Speed on individual arterial segments can fluctuate from heavily congested to no congestion and back in a few minutes. The segment speed and traffic region congestion estimates together may give a better understanding of the actual traffic conditions.

This dataset contains the current estimated speed for about 1250 segments covering 300 miles of arterial roads. For a more detailed description, go to: http://bit.ly/Q9AZAD.

The Chicago Traffic Tracker estimates traffic congestion on Chicago’s arterial streets (nonfreeway
streets) in real-time by continuously monitoring and analyzing GPS traces received from Chicago Transit Authority (CTA) buses. Two types of congestion estimates are produced every ten minutes: 1) by Traffic Segments and 2) by Traffic Regions or Zones. Congestion estimate by traffic segments gives the observed speed typically for one-half mile of a street in one direction of traffic.

Traffic Segment level congestion is available for about 300 miles of principal arterials. Congestion by Traffic Region gives the average traffic condition for all arterial street segments within a region. A traffic region is comprised of two or three community areas with comparable traffic patterns. 29 regions are created to cover the entire city (except O’Hare airport area).
This dataset contains the current estimated speed for about 1250 segments covering 300 miles of arterial roads.
There is much volatility in traffic segment speed. However, the congestion estimates for the traffic regions remain consistent for relatively longer period. Most volatility in arterial speed comes from the very nature of the arterials themselves. Due to a myriad of factors, including but not limited to frequent
intersections, traffic signals, transit movements, availability of alternative routes, crashes, short length of the segments, etc. speed on individual arterial segments can fluctuate from heavily congested to no congestion and back in a few minutes. The segment speed and traffic region congestion estimates
together may give a better understanding of the actual traffic conditions.

This dataset contains the historical estimated congestion for the 29 traffic regions, starting in approximately March 2018. Older records are in https://data.cityofchicago.org/d/emtn-qqdi. The most recent estimates for each segment are in https://data.cityofchicago.org/d/t2qc-9pjd.

The Chicago Traffic Tracker estimates traffic congestion on Chicago’s arterial streets (non-freeway streets) in real-time by continuously monitoring and analyzing GPS traces received from Chicago Transit Authority (CTA) buses. Two types of congestion estimates are produced every 10 minutes: 1) by Traffic Segments and 2) by Traffic Regions or Zones. Congestion estimates by traffic segments gives observed speed typically for one-half mile of a street in one direction of traffic. Traffic Segment level congestion is available for about 300 miles of principal arterials. Congestion by Traffic Region gives the average traffic condition for all arterial street segments within a region. A traffic region is comprised of two or three community areas with comparable traffic patterns. 29 regions are created to cover the entire city (except O’Hare airport area). There is much volatility in traffic segment speed. However, the congestion estimates for the traffic regions remain consistent for a relatively longer period. Most volatility in arterial speed comes from the very nature of the arterials themselves. Due to a myriad of factors, including but not limited to frequent intersections, traffic signals, transit movements, availability of alternative routes, crashes, short length of the segments, etc. Speed on individual arterial segments can fluctuate from heavily congested to no congestion and back in a few minutes. The segment speed and traffic region congestion estimates together may give a better understanding of the actual traffic conditions. Current estimates of traffic congestion by region are available at http://bit.ly/103beCf.

311 Service Requests received by the City of Chicago. This dataset includes requests created after the launch of the new 311 system on 12/18/2018 and some records from the previous system, indicated in the LEGACY_RECORD column.

For purposes of all columns indicating geographic areas or locations, please note that requests of the type 311 INFORMATION ONLY CALL often are entered with the address of the City's 311 Center.

This dataset displays location for vehicles that have been towed and impounded by the City of Chicago within the last 90 days. Illegally parked vehicles, abandoned vehicles and vehicles used for illegal activities may be towed by the Chicago Police Department, the Department of Streets and Sanitation, the Department of Revenue, Aviation and the office of the City Clerk. After a tow request is issued, an inventory number is assigned by the Department of Streets and Sanitation and a truck is dispatched to tow the requested vehicle to a City auto pound. Disclaimer: This dataset includes vehicles towed or relocated by the City of Chicago; it does not include vehicles towed by a private towing company.

Background Information:
Auto Pound Locations (http://j.mp/kG5sgF).
Tow Process Overview (http://j.mp/lfBOEP).
Common Towing Questions (http://j.mp/imFYlp).
Parking and Standing Violations (http://j.mp/ifW8Uj).
Related Applications: Find Your Vehicle (http://j.mp/lWn0S7).

The Chicago Park District issues swim advisories at beaches along Chicago's Lake Michigan lakefront based on E. coli levels. This map shows predicted E. coli levels -- with bubble size corresponding to predicted level -- and whether the predicted E. coli level was at least 235 Colony Forming Units (CFU) per 100 ml of water (red bubbles).

This map updates daily and its predictions depend on data from https://data.cityofchicago.org/Parks-Recreation/Beach-Lab-Data/2ivx-z93u. It will show no predictions from midnight until the new day's predictions have been generated.

The Chicago Park District maintains weather sensors at beaches along Chicago's Lake Michigan lakefront. These sensors generally capture the indicated measurements hourly while the sensors are in operation during the summer. During other seasons and at some other times, information from the sensors may not be available. See https://data.cityofchicago.org/id/qmqz-2xku for a dataset with similar measurements on the lake water, itself.

The Chicago Park District maintains weather sensors at beaches along Chicago's Lake Michigan lakefront. These sensors generally capture the indicated measurements hourly while the sensors are in operation during the summer. During other seasons and at some other times, information from the sensors may not be available. See https://data.cityofchicago.org/id/qmqz-2xku for a dataset with similar measurements on the lake water, itself. The sensor locations are listed at https://data.cityofchicago.org/d/g3ip-u8rb.

The Chicago Park District maintains sensors in the water at beaches along Chicago's Lake Michigan lakefront. These sensors generally capture the indicated measurements hourly while the sensors are in operation during the summer. During other seasons and at some other times, information from the sensors may not be available. See https://data.cityofchicago.org/d/k7hf-8y75 for a dataset with land-based weather measurements at selected beaches. The sensor locations are listed at https://data.cityofchicago.org/d/g3ip-u8rb.

Please note that sensor locations change with the Park District’s operational needs, primarily related to water quality. For more information on beach operations, please see https://www.chicagoparkdistrict.com/parks-facilities/beaches.

Count of applications by Community Area

This filtered view contains applications for preapprovals for Additional Dwelling Units (ADUs) that have been successfully processed and have an "Issued" status.

See the full dataset for all applications and more information about the ADU program.

Applications for preapprovals for Additional Dwelling Units (ADUs) received by the Department of Housing pursuant to the December 2020 ADU Ordinance. After issuance of an ADU preapproval, the owner must obtain a building permit from the Department of Buildings before constructing an ADU.

For a map of the eligible areas, please see https://data.cityofchicago.org/d/n8dk-kjjn.

For more information about ADUs in Chicago, visit http://www.chicago.gov/ADU.

Map of property currently or historically owned and managed by the City of Chicago. Please see https://www.chicago.gov/landsales for information on purchasing land from the City of
Chicago.

Note, 4/14/2023: Please see the end of this description for newly added columns. -- Property currently or historically owned and managed by the City of Chicago. Information provided in the database, or on the City’s website generally, should not be used as a substitute for title research, title evidence, title insurance, real estate tax exemption or payment status, environmental or geotechnical due diligence, or as a substitute for legal, accounting, real estate, business, tax or other professional advice. The City assumes no liability for any damages or loss of any kind that might arise from the reliance upon, use of, misuse of, or the inability to use the database or the City’s web site and the materials contained on the website. The City also assumes no liability for improper or incorrect use of materials or information contained on its website. All materials that appear in the database or on the City’s web site are distributed and transmitted "as is," without warranties of any kind, either express or implied as to the accuracy, reliability or completeness of any information, and subject to the terms and conditions stated in this disclaimer.

The following columns were added 4/14/2023:

- Sales Status
- Sale Offering Status
- Sale Offering Reason
- Square Footage - City Estimate
- Land Value (2022) -- Note: The year will change over time.

Map of foreclosed rental properties registered with the Department of Housing under the Keep Chicago Renting ordinance.

Foreclosed rental properties registered with the Chicago Department of Housing under the Keep Chicago Renting ordinance.

Prior to 12/12/2022, Owner and Owner Management Agent addresses could not be registered through the registration site so no City, State, or ZIP columns were present in this dataset. Because all previously existing records had Chicago addresses for Owner and Owner Agent, the City and State columns were populated when added to this dataset but ZIP values are only available from 12/12/2022 forward.

The Property Address is always in Chicago.

Public alerts for the Chicago Department of Public Health's (CDPH) Health Alert Network (HAN).

The HAN provides CDPH with the capacity for quick, efficient, reliable, and secure web-based communication with CDPH staff, providers of medical care, laboratories, first responders and other local public health agencies and partners. The HAN facilitates CDPH’s day-to-day activities, including outbreak detection, investigation, and emergency response.

This dataset is published as a convenience to complement the HAN site, itself. While alerts generally are published promptly, for uses involving risk to health and/or life, please contact the HAN team directly to discuss other methods of receiving alerts.

The contents of this dataset, the HAN site, and CDPH's Web site are not intended to be substitutes for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Professional medical advice should not be ignored because of something you have read on this data portal or any CDPH site.

The Chicago Park District maintains weather sensors at beaches along Chicago's Lake Michigan lakefront. These sensors generally capture the indicated measurements hourly while the sensors are in operation during the summer. During other seasons and at some other times, information from the sensors may not be available. See https://data.cityofchicago.org/id/qmqz-2xku for a dataset with similar measurements on the lake water, itself.

The Chicago Park District maintains weather sensors at beaches along Chicago's Lake Michigan lakefront. These sensors generally capture the indicated measurements hourly while the sensors are in operation during the summer. During other seasons and at some other times, information from the sensors may not be available. See https://data.cityofchicago.org/id/qmqz-2xku for a dataset with similar measurements on the lake water, itself.

The Chicago Park District maintains weather sensors at beaches along Chicago's Lake Michigan lakefront. These sensors generally capture the indicated measurements hourly while the sensors are in operation during the summer. During other seasons and at some other times, information from the sensors may not be available. See https://data.cityofchicago.org/id/qmqz-2xku for a dataset with similar measurements on the lake water, itself.