A synoptic assessment of water quality in two Great Lakes connecting channels.

We conducted a probabilistic water quality assessment of two Great Lakes connecting channels, the St. Marys River, and the Lake Huron-Lake Erie Corridor (HEC) in 2014-2015. We compared the condition of the channels to each other and to the up- and down-river Great Lakes with data from an assessment of the Great Lakes nearshore conducted in 2015. We assessed the condition of each channel as good, fair, or poor by applying the most protective water quality thresholds for the down-channel lake. Condition in the St. Marys River rated mostly fair for total phosphorus (TP) and mostly good for chlorophyll