Water quality data

Visitors can to find and download data from surface water monitoring sites located in Minnesota. Where available, you can also view the conditions of lakes, rivers or streams that have been assessed.

For the best results when using the map-based tools, your computer should:

  • Be using Internet Explorer 5.0 or later.
  • Have the screen resolution set at 1024 by 768 pixels.
  • Have pop-up blockers turned off.

View surface water monitoring sites and data

There are two ways for users to find surface water monitoring sites and data.

The text-based search tool is available for those who prefer it, or those with a slower Internet connection. This tool allows searches by station ID number, county, water body name, watershed, station type, name of organization that collected the data and by project name.

The map-based search tool for surface water monitoring sites and data allows you to use an interactive map to find sites. This tool also allows users to conduct searches by monitoring station name or by watershed.

To learn more about the types of information that can be found when viewing monitoring sites, visit the surface water monitoring sites and data page.

View surface water conditions (assessments)

For some water bodies, enough data has been collected to assess the conditions of the lake, stream or river. These water bodies can be found using a map-based viewer.

The assessments are required under the federal Clean Water Act. They are used to determine whether water bodies meet their intended uses, such as being suitable for fishing or swimming. Use the links that follow to learn more about these assessments.

Downloading data

Water quality data

Monitoring data from lakes and streams in Minnesota is available for download, on a station-by-station basis. Use the map-based search or text-based search to find a station.

Additional information about monitoring data is available on the EDA Help page.

Geographic data

Geographic data from the map-based search tool is also available for download. The data is in a shapefile format, suitable for use with Geographic Information Systems (GIS) software. Shapefiles are available for the following geographic layers:

Data collection and storage

The EDA system provides users with an array of different types of data: water quality measurements from lakes or streams; fish and insect population descriptors that can be useful to determine stream conditions; streamflow measurements; and information from facilities that discharge wastewater. Data is collected by a wide variety of local, state and federal organizations, as well as hundreds of volunteer monitors.

Much of the MPCA’s water clarity data is collected by voluntary citizen monitors. For information on how to participate, visit the Citizen Lake Monitoring Program page or the Citizen Stream Monitoring Program page.

Organizations who would like to collect and submit water quality data should review MPCA protocols and standards available on the Environmental Monitoring page. If you have questions about submitting your data to the MPCA, contact Brian Timerson at 651-296-7898, or submit a question to our comments form.

Water quality data is stored in Minnesota’s STORET database. STORET has two portions — one for data stored before 1998 (legacy STORET) and another for data stored since that time (modernized STORET). The modernized portion provides many more opportunities to store information, or “metadata,” about the measurement results.

Data downloaded from the EDA will be noted for whether it was drawn from legacy or modernized STORET, along with additional distinguishing metadata. Please note that questions about data collected by agencies other than MPCA in the legacy structure can only be answered by those agencies. Monitoring project information contained in the newer structure and displayed through the EDA, will provide the user with enough information to dig deeper for more metadata, as necessary.

The STORET database, designed and supported by the U.S. Environmental Protection Agency, but housed and maintained by the MPCA, is simply a well-organized storage space for water quality data. STORET is not a design for choosing monitoring locations or methods.

Glossary of terms

Listed below are words or terms users will come across when viewing water quality data or assessments.

BOD5 Field pH Temperature
Chlorophyll a Field turbidity Total Kjeldahl nitrogen
Conductivity Index of Biological Integrity Total nitrate/nitrite nitrogen
Dissolved oxygen Pheophytin-a Total phosphorus
E. Coli Sample depth Total suspended solids
Ecoregion Secchi depth Transparency
Fecal coliform Specific conductance