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About Us

This site is a service of the Great Lakes Commission, an interstate compact agency that promotes the orderly, integrated and comprehensive development, use and conservation of the water and related natural resources of the Great Lakes basin and St. Lawrence River. It provides public access to map-based tools and GIS data layers for the region that support fact-based decision-making.

For more information about the Great Lakes Commission please visit

We welcome your opinion. Please contact us with your questions, ideas and suggestions.