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What is the “Rule Curve Evaluation”?

The water levels of Rainy Lake and the Namakan Chain of lakes are regulated within upper and lower limits set by the International Joint Commission (IJC) – these limits are known as a “Rule Curve” that is meant to maintain sufficient water levels for a wide variety of uses and interests.  With the latest rule curve having been set in 2000, the IJC committed to reviewing those upper and lower limits in 2015.  The IJC establishes minimum and maximum discharge requirements in order to avoid “emergency conditions” as much as possibl appointed a Rainy and Namakan Lakes Rule Curves Study Board (Study Board) in August 2015.  This Study Board will provide the IJC with scientifically supported recommendations for the modification or retention of the 2000 Rainy and Namakan Lakes rule curves, considering the extensive research that has been done since 2009 and prior on the hydrologic, hydraulic, cultural, economic and environmental risk factors. The geographic scope of this study comprises Rainy Lake and the Namakan Chain of lakes, the connecting channels and the Rainy River downstream of Rainy Lake to Lake of the Woods, and the riparian areas adjacent to these water bodies.