This is a watershed shared almost equally between Canada and the U.S., the majority of it being undeveloped and utilized for timber production, hunting, fishing, hiking and other recreational opportunities. The majority of land within the Ontario portion is within Quetico Provincial Park where no development is permitted (logging, mining, hydroelectric development). One community, Lac La Croix First Nation, is within this watershed, on the Canadian side and in Minnesota, there are several headwater communities.

In 2014, Minnesota’s intensive watershed monitoring 10-year cycle began here and was completed in 2015. The MPCA and its partners monitored dozens of lakes and streams to assess water quality and compare it to state standards. Overall, water quality conditions are good to excellent and can be attributed to the forest and wetlands that dominate the land cover; any impairments (TSS, E coli and mercury in fish) are typically limited to the lower reaches where stressors from land use practices may accumulate. Historical and recent forest cover changes, along with urban/industrial development and draining of wetlands are likely stressors affecting biological communities within the watershed. The Stressor ID Report was completed in July 2019, and the WRAPS Report is due in the near future. All of the 245 monitored lakes, except for Blueberry Lake near Ely, had good-to-excellent water quality. The Blueberry Lake
impairment was deemed to be a result of natural conditions. For an overview of work being done in this watershed and to access the full monitoring and assessment report, go to:

In Ontario, as part of the Broadscale Monitoring Program, water quality data have been collected in the Rainy River headwaters from a random sample of lakes in 2010 and 2016. The sub-basin is entirely bedrock with the soil being primarily a thin layer of glacial till. Overall water quality conditions are good to excellent. Only one community at Lac La Croix First Nation and less than a dozen lakes with cottaging development are found here. There is no development within the Quetico Provincial Park portion of the watershed and no hydroelectric facilities or operating mines outside of the park where logging and related road construction is the major development activity. Studies within Quetico have found water chemistry to be primarily influenced by underlying bedrock geology (eg calcium, conductivity, pH). Because of the high proportion of granite bedrock, the watershed tends to have clearer waters that are slightly acidic with low phosphorus levels.

Photo Credit: P. Weber