Lake’s relentless rise takes a toll on coastline

Lake levels are rising significantly, and evidence can be seen along the Port Washington shoreline. Not only is there little sand to be found on the city’s north and south beaches, Mile Rock is virtually an island, water in the marina is closer to the top of the pilings and docks than it has been in years and erosion concerns have prompted officials to move some benches away from the bluff’s edge.

And it’s not likely things will change anytime soon. 

The Army Corps of Engineers reports that Lake Michigan’s water level is expected to be significantly higher than usual through October and seven to 10 inches higher than last year.

“These are the highest levels since the record was set in 1986,” Keith Kompoltowicz, chief of watershed hydrology at the Army Corp’s Detroit District, said Tuesday.

In April, he said, Lake Michigan was at 580.61 feet above sea level. The record high is 581.46 feet.

Those levels are only six to nine inches lower than the record high lake level,  Kompoltowicz said.

Given that it has only been six years since record lows were recorded on Lake Michigan, he said, the quick rebound is unusual.

“The amount of time it’s taken the lake to go from those record lows to average and then above average levels is quite astounding,” Kompoltowicz said. “Things don’t tend to happen very quickly on lakes.”

In the 24 months after Lake Michigan hit its record low in 2013, he noted, the lake experienced one of the largest increases in water levels since the Corps began keeping records in 1918.

But, Kompoltowicz said, lakes Michigan, Huron and Ontario are not expected to reach record levels this summer, while lakes Superior and Erie are forecast to break records.

The fact that water levels are high isn’t news to Port officials.

Recreation Director Kiley Schulte said that in the last year her department has had to move benches away from the edge of the bluff at Upper Lake Park due in part to erosion.

And, she said, there’s little beach for people to enjoy so far.

“People worry about the beach,” she said. “We have two beaches, and we’re hoping they’re there this summer.”

After all, Schulte said, while people wanting to take a dip to cool off have the option of visiting the city’s pool, it’s just not the same.

“Every community has a pool. The beach sets us apart,” she said. “There are a lot of people who love our beaches. People worry about what’s happening there — will we have a beach?”

Harbormaster Dennis Cherny said Monday that a seiche — when winds and atmospheric pressure cause lake levels to oscillate — last week increased the lake level 18 inches for a time.

And for the first time, people had to walk up, not down, the ramps leading from shore to the floating docks in the marina, he said.

“It was strange,” Assistant Harbormaster Lisa Rathke said. 

Now, Cherny said, they are level.

Cherny noted that the water is within six inches of the top of the pilings in the marina, where normally the lake is 24 to 30 inches from the top.

“If it goes over the pilings, there’s a risk that the piers will get off their track and get hung up on the pilings,” he said. “To solve that, we would need to weld extensions onto those pilings.”

And that, he said, would be costly, noting there are 124 pilings.

But, Cherny told the Harbor Commission Monday that he’s not ready to push the panic button yet.

“You don’t know until it’s here,” he said.

The reason for high lake levels is simple — a combination of a snowy winter and wet spring, along with a fair amount of runoff and little evaporation — Kompoltowicz said.

“In Wisconsin, you had one of the heaviest snowfalls in recently years,” he said. “Recently, we’ve had significant rain events.”

Rainfall, snow, runoff and evaporation combine to form what’s known as the net basin supply, Kompoltowicz said, and the net basin supply has been above average for four of the last six years. That’s because the precipitation and runoff components have been higher than the amount of evaporation.

The impact of rising lake levels will be seen in many lakeshore communities, Kompoltowicz said.

“Instances of coastal flooding and erosion are made worse,” he said. “Beach-goers are going to see smaller beaches.”

Shoreline property owners are expressing concerns about the loss of their land, Kompoltowicz said, and communities are worried about erosion, especially of the bluffs that overlook the lake, as waves eat away at the toe of the bluffs.

Kompoltowicz would not say whether climate change is at work.

“Climate change is a long-term shift,” he said. “We tend to focus on what’s happening right now and over the next six months.”

But, he said, unless the weather changes radically, high lake levels will be here to stay for some time.

“The conditions that would lead to lower levels are a hot, dry summer followed by a cool, dry fall and a cold, snowless winter,” he said, noting that would not only decrease precipitation levels but also lead to higher evaporation rates.

But for Schulte, the high lake levels are a warning.

“It’s a testament to how much we need to take care of our environment and deal with things like climate change,” she said.