Institutional requirements for watershed cumulative effects assessment and management: Lessons from a Canadian trans-boundary watershed

Watersheds are under increasing stress from the cumulative environmental effects of water and land use disturbances caused by both anthropogenic and natural causes. Yet, while the science of watershed cumulative effects assessment and management (CEAM) is advancing much less is known about the institutional and capacity requirements to implement and sustain watershed CEAM. Based on lessons from a transboundary watershed in western Canada this paper presents eight institutional requirements, or requisites, for the implementation of watershed-based CEAM. We suggest that effective watershed CEAM requires government leadership to move beyond the current inward focus on project approvals toward an outward focus on the cumulative effects of all disturbances in a watershed; complementary monitoring programs at the project and watershed scale, and a means to ensure the sharing of monitoring data across watershed stakeholders; and a nested planning framework to coordinate watershed planning objectives with individual project impact assessment and decision making. Results of this paper show that simply scaling up from individual project-based assessments to the watershed scale exposes many institutional constraints that can impede CEAM action.

► Project scale assessment is inadequate to manage cumulative effects in watersheds.
► We identify eight requisites for effective watershed-based CEAM.
► A lead agency is needed to set watershed targets and coordinate CEAM.
► Watershed CEAM requires complementary monitoring at the project and watershed scale.
► Terms of reference for project assessment must be developed in a watershed context.