Groves within the Forest Preserve District of Cook County. To view or use these shapefiles, compression software and special GIS software, such as ESRI ArcGIS, is required.

Public art located in Chicago parks. To view or use this KMZ file, compression software, such as 7-Zip, and special GIS software, such as Google Earth, are required. To download this file, right-click the "Download" link above and choose "Save link as."

The Chicago Park District tests water samples at beaches along Chicago's Lake Michigan lakefront, which it tests for E. coli in order to monitor swimming safety. Multiple samples may be taken from a beach and samples may be tested by culture, DNA testing, or both.

What do these numbers mean?

The modeling prediction numbers forecast real-time Escherichia coli (E. coli) bacteria levels present in the water. The Chicago Park District (CPD) in partnership with the US Geological Survey, has developed statistical prediction models by using weather data pulled from CPD buoys (https://data.cityofchicago.org/d/qmqz-2xku) and weather stations (https://data.cityofchicago.org/d/k7hf-8y75). E. coli is an indicator species for the presence of disease-causing bacteria, viruses, and protozoans that may pose health risks to the public.

The culture based testing numbers indicate E. coli levels present in the water. This method requires 18-24 hours of processing to receive results. US Environmental Protection Agency (USEPA) recommends notifying the public when E. coli bacteria levels are above the federal water quality Beach Action Value (BAV), which is 235*CFU. When bacteria levels exceed 235 CFU, a yellow or red flag will be implemented. This standard is used at beaches throughout the Great Lakes region. For more information please refer to the USEPA Recreational Water Quality Criteria.

The rapid testing method (qPCR analysis) is a new method that measures levels of pathogenic DNA in beach water. Unlike the culture based test that requires up to 24 hours of processing, the new rapid testing method requires a few hours for results. The Chicago Park District can use results of the rapid test to notify the public when levels exceed UPEPA recommended levels. US Environmental Protection Agency (USEPA) recommends notifying the public when DNA bacteria levels are above the federal water quality Beach Action Value (BAV), which is 1000*CCE. When DNA bacteria levels exceed 1000 CCE, a yellow or red flag will be implemented. For more information please refer to the USEPA Recreational Water Quality Criteria (http://water.epa.gov/scitech/swguidance/standards/criteria/health/recreation).

* The unit of measurement for Escherichia coli is Colony Forming Units (CFU) per 100 milliliters of water.
*The unit of measuring DNA is Enterococci Calibrator Cell Equivalents (CCE) per 100 milliliters of water.

The Chicago Park District tests water samples at beaches along Chicago's Lake Michigan lakefront, which it tests for E. coli in order to monitor swimming safety. Multiple samples may be taken from a beach and samples may be tested by culture, DNA testing, or both.

What do these numbers mean?

The modeling prediction numbers forecast real-time Escherichia coli (E. coli) bacteria levels present in the water. The Chicago Park District (CPD) in partnership with the US Geological Survey, has developed statistical prediction models by using weather data pulled from CPD buoys (https://data.cityofchicago.org/d/qmqz-2xku) and weather stations (https://data.cityofchicago.org/d/k7hf-8y75). E. coli is an indicator species for the presence of disease-causing bacteria, viruses, and protozoans that may pose health risks to the public.

The culture based testing numbers indicate E. coli levels present in the water. This method requires 18-24 hours of processing to receive results. US Environmental Protection Agency (USEPA) recommends notifying the public when E. coli bacteria levels are above the federal water quality Beach Action Value (BAV), which is 235*CFU. When bacteria levels exceed 235 CFU, a yellow or red flag will be implemented. This standard is used at beaches throughout the Great Lakes region. For more information please refer to the USEPA Recreational Water Quality Criteria.

The rapid testing method (qPCR analysis) is a new method that measures levels of pathogenic DNA in beach water. Unlike the culture based test that requires up to 24 hours of processing, the new rapid testing method requires a few hours for results. The Chicago Park District can use results of the rapid test to notify the public when levels exceed UPEPA recommended levels. US Environmental Protection Agency (USEPA) recommends notifying the public when DNA bacteria levels are above the federal water quality Beach Action Value (BAV), which is 1000*CCE. When DNA bacteria levels exceed 1000 CCE, a yellow or red flag will be implemented. For more information please refer to the USEPA Recreational Water Quality Criteria (http://water.epa.gov/scitech/swguidance/standards/criteria/health/recreation).

* The unit of measurement for Escherichia coli is Colony Forming Units (CFU) per 100 milliliters of water.
*The unit of measuring DNA is Enterococci Calibrator Cell Equivalents (CCE) per 100 milliliters of water.

KML file of trails within the Forest Preserve District of Cook County. To view or use these files, special GIS software such as Google Earth is required.

KML file of fishing lakes in Cook County with contours. To view or use these files, special GIS software such as Google Earth is required

Buildings located in Chicago parks. To view or use this KMZ file, compression software, such as 7-Zip, and special GIS software, such as Google Earth, are required. To download this file, right-click the "Download" link above and choose "Save link as."

Facilities and features in Chicago parks. For more information, visit http://www.chicagoparkdistrict.com/facilities/search/. To view or use this KMZ file, compression software, such as 7-Zip, and special GIS software, such as Google Earth, are required. To download this file, right-click the "Download" link above and choose "Save link as."

KML file of shelters within the Forest Preserve District of Cook County. To view or use these files, special GIS software such as Google Earth is required.

KML file of groves within the Forest Preserve District of Cook County. To view or use these files, special GIS software such as Google Earth is required

The Chicago Park District maintains 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/tz6n-cnmj for a filtered view of this dataset that hides some off-season and other records without generally useful data.

The Chicago Park District issues swim advisories at beaches along Chicago's Lake Michigan lakefront based on predicted E. coli levels. This dataset shows the predictions and whether a swim advisory was issued due to the predicted E. coli level being at least 235 Colony Forming Units (CFU) per 100 ml of water.
The data used to make the predictions can be found in https://data.cityofchicago.org/d/qmqz-2xku and https://data.cityofchicago.org/d/k7hf-8y75. The measured E. coli levels determined later can be found in https://data.cityofchicago.org/d/2ivx-z93u.