International Lake Superior Board of Control

Anglers and other users of the St. Marys Rapids are advised that on Wednesday morning, May 11, 2022, Gates #9 through #12 will be raised from their current position to a setting of 33 cm (13 in) open for the remainder of the month. Gates #7 and #8 will remain at their current setting of 20 cm (8 in). There will be no change to the setting of Gate #1, which supplies a flow of about 15 m3/s to the channel north of the Fishery Remedial Dike. These gate movements will result in an increase in the flow through the St. Marys Rapids from approximately 85 m3/s (3,000 cfs) to approximately 156 m3/s (5,500 cfs).

Outflows from Lake Superior and into Lake Michigan-Huron continue to be set in consideration of water levels upstream and downstream. The Board expects the total outflow to be 1,910 m3/s (67 tcfs) in May, which is as prescribed by Lake Superior Regulation Plan 2012. The gate setting at the Compensating Works will be maintained at the setting equivalent to one-half gate open (Gates #7 through #10 partially open 20 cm (7.9 in)). There will be no change to the setting of Gate #1, which supplies a flow of about 15 m3/s to the channel north of the Fishery Remedial Dike.

Lake Superior water levels remain below the seasonal long-term average while Lake Michigan-Huron water levels remain above the seasonal long-term average. Lake Superior outflows continue to be set in consideration of water levels upstream and downstream.

Lake Superior and Lake Michigan-Huron water levels are near their seasonal low point and depending on weather and water supply conditions could begin their seasonal spring rise over the coming weeks. The gate setting at the Compensating Works will be maintained at the setting equivalent to one-half gate open (Gates #7 through #10 partially open 20 cm (7.9 in)). There will be no change to the setting of Gate #1, which supplies a flow of about 15 m3 /s to the channel north of the Fishery Remedial Dike.

Weather and water supplies to Lakes Superior and Michigan-Huron were much drier than average in January. Lake Superior water levels remain below the seasonal long-term average while Lake Michigan-Huron water levels remain above the seasonal long-term average.

The Board expects the total outflow to be 1,730 m3/s (61.1 tcfs) in January, which is as prescribed by Lake Superior Regulation Plan 2012. The gate setting at the Compensating Works will be maintained at the setting equivalent to one half gate open (Gates #7 through #10 partially open 20 cm (7.9 in)). There will be no change to the setting of Gate #1, which supplies a flow of about 15 m3/s to the channel north of the Fishery Remedial Dike.

Lake Superior outflows continue to be set in consideration of water levels upstream and downstream. The gate setting at the Compensating Works will be maintained at the setting equivalent to one half gate open (Gates #7 through #10 partially open 20 cm (7.9 in)). There will be no change to the setting of Gate #1, which supplies a flow of about 15 m3/s to the channel north of the Fishery Remedial Dike.

Lake Superior and Lake Michigan-Huron have both continued their seasonal declines in September. As a result of the drier than average conditions, water levels on Lake Superior have gone below the seasonal long-term average for the first time since April 2014.

Anglers and other users of the St. Marys Rapids are advised that the gate setting of the Compensating Works structure at the head of the Rapids will be adjusted on September 27, 2021. The four middle gates (Gates #7 through #10) will be closed and four gates on the US side of the structure (Gates #11 through #14) will be partially opened to a setting of 20 cm (8 in.).