On behalf of three Aboriginal communities in the oil sands region of northern Alberta, we completed scientific reviews of the water quality, hydrology and fisheries components of several major environmental impact assessments for oil sands mines and SAGD projects. In some cases, tributaries of the Athabasca River were proposed for diversion, removal or closed-circuiting to allow for the advancement of projects. We have also worked with Fisheries and Oceans Canada in reviewing the design of fish habitat (No Net Loss) compensation lakes, watershed management frameworks, and other aspects of oil sands project design that impact local watersheds and fish. Provided recommendations for additional mitigation.