“This winter has been extreme on many levels,” said Keith Kompoltowicz, a hydrologist for the U.S. Army Corps of Engineers. “All of this will impact the water levels of the Great Lakes. We’ve had near-record-setting snowfall for many places across the Great Lakes basin.”
The Corps of Engineers reported Wednesday that the increased snowfall and record ice coverage have led to a positive trend for the lakes. According to Kompoltowicz, Lake Michigan’s average water level for February was 577.26 feet — 13 inches higher than a year ago, but still about 13 inches below the long-term average.
“We have rebounded significantly since setting that record low,” he said.
Over the next six months, the lake is expected to rise another 14 inches. But if the region has a wet, rainy spring, the rise could be as much as 22 inches, Kompoltowicz said.
One factor leading to the corps’ positive water forecast is a solid snowpack. They say the Lake Michigan basin’s snow-water equivalent — a measure of how much water is in the snow and ice — is about 4-8 inches, all of which could make its way into the big lake.
“There is a lot of water in the snow sitting on the ground, waiting to melt,” Kompoltowicz said. “It’s the highest it has been in the past decade. … The snow-water equivalent is 30 percent higher than the average in the past decade.”
“According to the Midwest Climate Center, much of the Great Lakes region experienced below-normal temperatures,” Kompoltowicz said. “Given the cold temperatures, that leads to extensive ice coverage on the Great Lakes.”
This coverage has contributed to increased water levels, since it inhibits evaporation.
“This winter is certainly more severe than the past few winters,” Great Lakes Environmental Research Laboratory scientist George Leshkevich said.
Leshkevich said Lake Michigan is about 92 percent covered, shy of a record set in 1977 when it was 93.1 percent covered by ice. He said it’s the first time since 1994 that four of the five Great Lakes have been 90 percent or more ice-covered.
Leshkevich noted that the 40-year average for ice coverage on Lake Michigan for February is 32 percent. The average for last month was about 77 percent.
With all the snow and ice waiting to turn to liquid, experts warn that flooding could be prevalent in the coming weeks.
“Across the southern part of the Great Lakes basin, there is quite a high threat of flooding as the snow begins to melt as we move into the spring,” Kompoltowicz said. “Any additional rainfall on top of the snowpack would add to the flood threat.”
The hydrologist added that ice could cause problems if the ice breakup on rivers that feed the lakes becomes clogged.
With this threat looming, Ottawa County officials met recently to prepare for flooding. They’ve urged residents to prepare by clearing roof drains and catch basins, and shoveling snow from the foundations of their homes.
The Ottawa County Emergency Management department also encourages residents to keep checking waterways and drains nearby during the spring season.