A Cumulative Impact Assessment for the Great Lakes-St. Lawrence River Basin

Analyzing the cumulative impacts of water withdrawals is an important method for determining the effect of water uses on a given source. Understanding the impacts of individual and cumulative water withdrawals from a water system is essential for water users, managers, and other decision makers. Cumulative impact analysis at the watershed scale, especially at the magnitude of the Great Lakes, is in its infancy, but carries significant promise and far-reaching implications. This is the first assessment of cumulative impacts ever conducted on a scale similar to the Great Lakes-St. Lawrence River Basin anywhere in the world.The cumulative impact assessment will inform decision-making and other regulatory functions. The multiyear, data-intensive process draws on the joint effort of State, Provincial, and Federal agencies and represents a significant step forward in resource management at the watershed scale. It also provides a model for others regions seeking to gain a better understanding of their watershed for management and regulatory purposes.