Critical intersections of flow: Connecting waters among the Laurentian Great Lakes

The various physical alterations of connecting waters that affect natural water flow cycles and habitat quality. An analysis of the state of water quality and ecosystem services in the rivers (St. Marys, St. Clair, Detroit, Niagara, St. Lawrence), fluvial lake (St. Clair), and strait (Mackinac) that connect and drain the Laurentian Great Lakes was conducted by the Great Lakes Science Advisory Board of the International Joint Commission (Canada, United States of America). Although these boundary waters are defined under the Great Lakes Water Quality Agreement and are associated with lakewide management plans, they have historically received inadequate attention regarding surveillance and monitoring. As a result, the data and knowledge bases for connecting waters are far less complete than for the open water and nearshore regions of the lakes, given the intensity of threats and the ecosystem services that intersect in connecting waters. This commentary reviews and discusses the current status of monitoring infrastructure and activities in the Great Lakes connecting waters. Several specific recommendations are made to support development of integrated connecting water research and practice: the development of highly qualified personnel trained to conduct research on large moving waters; establishment of well-equipped and staffed research vessels with appropriate sampling gear; support for shore-based university and agency laboratories to focus on a mix of long-term reference stations and experimental studies; expanded use of real-time monitoring systems using evolving technologies; and increase in Indigenous community technical capacity for environmental monitoring and management to collectively improve ecological and human health knowledge and management in a more coordinated fashion.