DETROIT, M.I. (WWTI) — Water levels on the Great Lakes are expected to rise as temperatures increase this spring.

According to the U.S. Army Corps of Engineers, water levels on the Great Lakes remain above their long-term averages except for Lake Superior.

As of April 1, Lake Ontario was 20 inches above its 2021 level and Erie was nearing its 2021 level. Water levels on all other Great Lakes were lower than one year prior.

Additionally, over the next week, the Great Lakes basin is also expected to receive an average of 1.25 inches of precipitation, with isolated pockets of over 1.5 inches in the eastern Lake Ontario region.

Due to increased precipitation and warming temperatures, USACE predicted that by May 1, Lake Ontario will rise six inches, Lake St. Clair will increase two inches and a four-inch rise will be seen on Lakes Superior, Michigan-Huron and Erie.

Predictions also indicate that Lake Ontario’s outflow through the St. Lawrence River will remain above average through the month of April. Outflows will also be above average on the St. Clair River and Niagara River.

Specific water level rates are listed in the chart below:

OntarioErieSt. ClairMichigan-HuronSuperior
Water level for April 1, 2022
Difference from level on
April 1, 2021 (inches)
Difference from long-term
monthly average of April (inches)
Projected net change by
May 1, 2022 (inches)

All values for specific days in the chart above are based on a three-day daily average around the specified date.

Measured water levels are still-water surface elevations over the entire lake surface. Levels at specific locations may differ substantially.

The USACE warned that Great Lakes, connecting channels and St. Lawrence River users should keep informed of current conditions before undertaking any activities affected by changing water levels. Mariners should utilize navigation charts and refer to current water level readings.