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Water Well Database

The County Well Index (CWI) is a data base that contains information for over 533,000 water-wells drilled in Minnesota. The data are derived from water-well contractors' logs of geologic materials encountered during drilling. Confirmed locations and interpreted geologic well records are available for over 340,000 of the wells. Available data also include casing, screen and pump information.

CWI is now Web accessible at CWI ONLINE. The data base can be searched and files printed. Files cannot be downloaded.

Due to the Homeland Security Act of 2002, wells supplying public water systems will not be displayed in CWI Online. If you need access to this information, contact Mike Baker at the MN Department of Health 651-201-4651. This restriction also applies to downloadable files.

If a CD or downloadable file is required, contact the MGS Map Sales Office. Please print the order form to mail a request.

Frequently asked questions about CWI. This FAQ does not include information about the web based CWI. Please refer to the help files for CWI Online.

Attribute definitions for unit stratigraphy and well use can be found in the linked pdf files.

NOTICE: Changes were made to CWI stratigraphic nomenclature on August 1, 2014.