International Lake Superior Board of Control

Lake Superior and Lake Michigan-Huron water levels continue to decline, but are still well above average and the risk of high-water impacts remains.  Lake Superior outflows continue to be set in consideration of high levels upstream and downstream.

Lake Superior generally remained stable over the course of the month, which is typical for this time of year. Lake Michigan-Huron declined 4 cm (1.6 in) over the course of the month, which is the average water level decline in August.

Basin conditions were generally wetter than average in July. As a result, water levels rose on Lake Superior and remained stable on Lake Michigan-Huron.

Basin conditions were generally near average or drier than average in June, around both Lake Superior and Lake Michigan-Huron. As a result, water levels did not rise as much as they typically do in June.

While conditions around Lake Superior were drier than average in May, conditions were again wetter than average on Lake Michigan-Huron, driven by a couple of significant rainfall events in the middle and at the end of the month.

Conditions across the Great Lakes were generally drier this past month and the water levels of both Lake Superior and Lake Michigan-Huron rose less than they typically do in April. Nonetheless, an exceptional volume of water remains in the system.