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New WQX 3.0 profiles are available at waterqualitydata.us/beta/. These profiles will contain recent USGS data added since March 11, 2024, which marks the beginning of limited accessibility for USGS data. Read more about the 3.0 profiles and associated changes here.

This legacy user interface will continue to function for several weeks. However, this user interface only serves WQX2.2 profiles, which do NOT contain USGS data added after March 11, 2024.

WQP Home >  Providers >  NWIS >  USGS-IL >  USGS-414948087304401

Lake Michigan 4 miles offshore from Chicago (USGS-414948087304401) site data in the Water Quality Portal

Data Provider: NWIS (Learn more about Water Quality Portal Data Providers)

This lake, reservoir, impoundment site, maintained by the USGS Illinois Water Science Center (identifier USGS-IL), has the name "Lake Michigan 4 miles offshore from Chicago" and has the identifier USGS-414948087304401. See more details of this site the the USGS NWIS Web page for this site.

This site is located in Cook County County, Illinois at 41.83021944000000 degrees latitude and -87.5123694000000 degrees longitude using the datum NAD83. The horizontal location collection method was "Mapping grade GPS unit (handheld accuracy range 12 to 40 ft)" and the accuracy is 1 seconds. The source map scale is 1:24000.

To download the metadata about this site along with water quality data, go to the Portal Page and enter "USGS-414948087304401" into the "Site ID" box under Site Parameters

What other monitoring locations are upstream or downstream from this one?

Upstream and downstream locations

This map shows all Water Quality Portal stations that are 10 miles upstream (dashed dark blue) and 10 miles downstream (solid light blue) of this monitoring location (indicated by the large blue circle). The upstream and downstream functionality is provided by the Network Linked Data Index.

When were data collected at this location?

Periods of record for data characteristic groups

For a more detailed breakdown of data, go to the Monitoring Report at the EPA How's My Waterway Application
Characteristic Group Date Range*
Biological, Algae, Cyanobacteria 2023 - 2023
Biological, Algae, Phytoplankton, Photosynthetic Pigments 2023 - 2023
*Date ranges may contain gap years

What other information is available for this location?

Detailed Metadata

For the definitions of the metadata elements, please go to the Water Quality Portal user guide

Location Metadata Value
OrganizationIdentifier USGS-IL
OrganizationFormalName USGS Illinois Water Science Center
MonitoringLocationIdentifier USGS-414948087304401
MonitoringLocationName Lake Michigan 4 miles offshore from Chicago
MonitoringLocationTypeName Lake, Reservoir, Impoundment
LatitudeMeasure 41.83021944000000
LongitudeMeasure -87.5123694000000
SourceMapScaleNumeric 24000
HorizontalAccuracyMeasure/MeasureValue 1
HorizontalAccuracyMeasure/MeasureUnitCode seconds
HorizontalCollectionMethodName Mapping grade GPS unit (handheld accuracy range 12 to 40 ft)
HorizontalCoordinateReferenceSystemDatumName NAD83
CountryCode US
StateCode 17
CountyCode 031
ProviderName NWIS