Great Lakes levels to top or be near record highs well into 2020, Army Corps predicts
Despite below-average precipitation and seasonal decline, Great Lakes water levels remained near record highs in November, the U.S. Army Corps of Engineers reported.
After a year of some of the worst flooding ever in parts of the Midwest, concern is rising that the spring of 2020 may see more high water in areas that still are struggling after deluges.
The levels findings the corps released this week come after the Great Lakes Basin saw its wettest 60-month period ending Aug. 31 in 120 years of record-keeping, according to corps records.
The continued high levels signal that winter storms could bring more coastal flooding and erosion. Storms also could cause ice floes and jams, which could clog channels that empty into the lakes, affecting water flow and leading to flooding, experts say.
The mean levels for lakes Superior, Michigan, Huron, Erie, St. Clair and Ontario were about a foot higher than the same month in 2018, according to the monthly bulletin from the Army Corps' Detroit office.
The November mean water levels were: Superior, 603.05 feet; Michigan-Huron, 581.56; St. Clair, 576.48; Erie, 573.10; Ontario, 246.19.
The report showed those levels all were within 1-2 feet of record highs set in 1945, 1985 and 1986.
At the same time, preliminary estimates indicate each lake had below-average precipitation in November.
"Precipitation was closest to normal in the Lake Michigan-Huron basin, estimated at about 78% of its average," researchers said. "Totals were the lowest, as compared to average, in the Lake Ontario basin, at only 41% of average."
However, despite the drier conditions, "all basins except Lake Superior received above average water supplies," the analysis said. "This is likely due to the influence of
enhanced runoff from the wet weather in October."
The lakes entered or continued their seasonal decline in November, the corps said. That trend is slated for all of the lakes expect Erie, which was expected to remain at the same level in December, then drop off in January.
High levels eroded shorelines across the state last summer. The damage has prompted state officials to streamline the permitting process to place sandbags along lakeshore property.
Flooding ravaged much of the Missouri and Mississippi River basins and their tributaries earlier this year, reaching record levels and overwhelming levees in many places. This fall, parts of the Missouri River were slightly above flood stage at a time of the year when river levels traditionally run low, the Associated Press reported.
Areas along the Missouri River in parts of Nebraska, Kansas, Iowa and Missouri were particularly ravaged in the early spring, damaging hundreds of homes and businesses.
In Michigan, state lawmakers Thursday asked Gov. Gretchen Whitmer to declare a state of emergency for the Lake Michigan shoreline after high lake levels damaged property and triggered erosion this year.
“What we’re witnessing along the lakeshore has been truly heartbreaking,” said state Rep. Bradley Slagh, R-Zeeland, said. “Homes and businesses have been damaged or destroyed by the effects of wind and water. Even state parks and local roadways have been tremendously impacted by the brunt of rising water levels of Lake Michigan.”