Potential Ecological Effects of the Proposed GRAND Canal Diversion Project on Hudson and James Bays

Abstract

The GRAND Canal scheme, which by the construction of a dike across James Bay would divert 61% of Hudson Bay's freshwater budget south, has ecological implications for the North. The formation of ice in Hudson Bay could increase as its pycnocline develops earlier in the spring and deepens in the summer and ice breakup is delayed because of the removal of the warm James Bay outflow in the spring. A reduction in primary productivity could result because of changes in the pycnocline's development, the removal of nutrients normally associated with spring's melting ice and a decrease in stable stratification periods as the dike removes the dampening action of James Bay on tidal and wind-generated disturbances. Changes in nutrient content and freshwater circulation out of Hudson Bay could potentially affect productivity downstream on the Labrador Shelf, and changes in productivity and ice pack within Hudson Bay would detrimentally affect fishes and marine mammals. Changes to coastal staging areas in both bays would most likely destroy a major portion of the North American migratory bird population. A resurgence of interest in the GRAND Canal scheme necessitates further research to provide data for the many unanswered questions concerning the potential ecological impacts of the diversion.

Key words: GRAND Canal, diversion, Hudson Bay, James Bay, pycnocline, phytoplankton, productivity, ecological impact, climate modification