What is a seiche?

SANDUSKY — The seiche event on Jan. 13 that lowered the lake on the western side of Lake Erie and raised it on the eastern side wasn't unusual. But it was uncommon for it to happen in the middle of winter, said experts participating in a U.S. Army Corps of Engineers Learn about Lake Erie Seiche information session. It took place Thursday at Toledo's main public library building, which was also offered by internet video. A seiche is an interesting wind phenomenon that occurs on Lake Erie. Winds on Lake Erie typically blow in from the west. When there's a strong wind, it can lower lake levels on the western side of the lake by several feet and raise them by several feet on the eastern side, in the Buffalo, New York, area. Recent examples of seiche events on Lake Erie include on Jan. 13, Dec. 24, 2022, and Nov. 15, 2020. When a seiche occurs, it can lower the water so much on the west side that boats in Toledo will rest on the lake bottom while the rise of water in the east can cause flooding in Buffalo. On Jan. 13, water rose 4.83 feet in Buffalo. The big 2020 seiche caused almost 14 feet of difference between the eastern and western lake elevations. While seiches commonly can occur late in the year, in the past, ice cover has tended to block water movement for much of the winter, shutting down seiches. That may be changing due to the current trend of less ice cover in the winter on Lake Erie, experts said Thursday. "Historically, the largest seiches tend to occur in the November/December time frame when the lake is wide open. With the lake remaining open later in the winter, we can expect seiches to occur throughout the winter," commented Weston Cross, a coastal engineer for the Buffalo District of the U.S. Army Corps of Engineers. Similarly, engineer Colleen O'Connell said, "From my experience, Lake Erie usually 80% or more ice cover in January. So I think having such an event mid-winter is unusual. (About) 30 to 40 years ago, I think you would see Lake Erie completely ice-covered during the winter." As the Register recently reported, Lake Erie in recent years has had less ice cover, a trend that might be connected to the warming attributed to climate change. Drawdowns of water levels on the western side of the lake can mess with water intakes used by coastal cities, said Madeleine Dewey, an engineer who works as a coastal planner for the Army Corps of Engineers. A certain amount of water needs to be above the intake, Dewey said. Seiches can be dangerous because conditions can change pretty quickly, and lives have been lost when people were swept off piers and jetties, Dewey said. Residents on the western side have enjoyed seeing the exposure of shipwrecks on the west side of the lake. But they should keep in mind that water comes flowing back when a seiche occurs, Dewey said. "That water is going to be sloshing back at some point," Dewey said. The water surges associated with seiches also can cause major shoreline erosion, she said. The Army Corps of Engineers has been working on a seiche study that draws on water levels measured at 14 different locations on Lake Erie over a period of more than 30 years, Dewey said. The final report is still in the works and is not publicly available yet, but it should be released this spring and it will be posted online, she said.