Lake Michigan approaching record water levels

WIS. (WFRV) — Since its low point in 2013, water levels in Lake Michigan have been on a stead rise over the last several years. This is increasing the potential for lakeshore flooding and erosion along Lake Michigan and the bay of Green Bay.

“So the water levels are high right now and the first thing to understand about the great lakes water levels is that they undergo cycles. They are natural variations. Sometimes they’re high and sometimes they’re low and these are over several years where you go from a high to a low level. And if you look at a long history which we have of many decades of water levels you can see that clearly in the record.” -Paul Roebber UW-Milwaukee Professor of Atmospheric Science

There are several factors that play a role in the water levels such as precipitation over and around the lake as well as evaporation.

“The drainage basins are extremely large for the great lakes as you can imagine so it doesn’t have to be raining right over the lake for you to have runoff to go into the lake eventually to raise the lake levels. Precipitation drives about 90 percent of the variation of the water levels so if you get more snow in the winter time or rain in the summertime you generally will see the lake levels rise.”

The last record high set in the Michigan-Huron system was in te mid-1980s when water levels reached 582.35 feet. That was close to 3.5 feet above the long-term average.

“You can talk about conditions in which the levels above the long-term average can be several feet above that average. The impact of that is that you can have a lot of shoreline erosion. Here in the Milwaukee area we ve a lot of places that are sort of on the bluffs over the shore and you get a lot of erosion on those bluffs. People who have houses and other things close to those bluffs are concerned obviously because of that erosion so that’s one of the big impacts.

Water levels in the Lake Michigan-Huron system are expected to be near 581 feet for the month of May. The National Weather Service also monitors the water levels closely and is prepared to issue various alerts to warn the public of potential dangers.