Keith Kompoltowicz, chief of watershed hydrology for the Corps of Engineers’ Detroit District, said Lakes Michigan and Huron are expected to be 7-9 inches higher in spring 2018 compared to this past spring.
Lakes Huron and Michigan are measured as one unit by the Corps of Engineers.
According to the data, all of the Great Lakes are expected to remain above long-term averages when it comes to water levels through the spring. Lake Ontario is expected to be close to its long-term average, while the rest of the Great Lakes are expected to be significantly above averages.
Kompoltowicz said instances of erosion and shoreline flooding have occurred on all of the Great Lakes within the past few years.
“Anytime you get those higher-than-average levels, the waves break closer and closer to infrastructure and shoreline protection,” he explained. “Erosion and shoreline flooding will continue under these circumstances.”
Kompoltowicz said the corps is working on updated forecasts for the Great Lakes’ levels, which will include predictions for next month through May 2018.
“It’s certainly a concern for those with property along the Great Lakes, and the Great Lakes are very powerful bodies of water, which can stir up large waves very quickly,” he said.
Drew Gronewold, a hydrologist with the Great Lakes Environmental Research Laboratory, said water levels are part of a cyclical process. The Great Lakes normally rise in the spring as snow melts, peak in August or July, and then decrease in November and October as water evaporates from the lakes at a high rate.
Water levels usually hit a low for the year in the winter months. If that process continued with average snowfall, average runoff in the spring and average evaporation in the fall, then water levels would stay around the same, Gronwold said.
Since early 2013, precipitation in the Great Lakes region has been above average and evaporation has been below average. Gronewold said this is the cause behind the increase in water levels since 2013.
If there is an abundant snowfall this winter and wet conditions in the spring, it is possible that Lakes Michigan and Huron could approach the record high levels of 1986.