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St. Marys rapids flows, water levels expected to rise in August

Water supplies in the Lake Superior basin were near average for the month of July
St Marys Rapids stockMP
The St. Mary's River rapids are pictured in this file photo. Michael Purvis/SooToday

The International Lake Superior Board of Control is advising anglers as well as other users of the St. Marys rapids that flow and water levels will increase this month.

As of Friday, the flow of the rapids is expected to be approximately 923 cubic meters per second (m3/s).

The increased flow is expected to cause some flooding of low-lying areas including the recreation trails on Whitefish Island.

Meanwhile, water supplies in the Lake Superior basin were near average in July.

The lake rose 4 cm last month, which is near the seasonal long-term average of 5 cm for July. Lake Michigan-Huron saw drier than average water supplies for the month and declined by 2 cm.

As of the beginning of August, the water level for Lake Superior is 10 cm above the seasonal long-term average while the Lake Michigan-Huron level is up 21 cm.

Pending weather ad water supply conditions for the month, the Lake Superior Board of Control also noted that the lake could rise as much as 8 cm though its seasonal decline is also a possibility to begin in August.