What will Lake Huron’s shoreline look like in 100 years? Here’s the map

Shoreline change is a problem plaguing many Great Lakes communities as locals watch parts of it slide into the water.

Now the Maitland Valley Conservation Authority in southwestern Ontario has produced much-needed maps showing the massive impact of these shifts in temperature and weather – large parts of Lake Huron’s shoreline could be submerged in 100 years, including cottages, waterfronts and a marina.

“It’s really the most shocking thing for me to see,” Patrick Huber-Kidby said of land already gone.

Huber-Kidby is a supervisor of planning and regulation at the Conservation Authority, located along the southeastern edge of Lake Huron north of London.

The maps are for municipalities and the province to have better information for future planning, and they also share them with the public

Huber-Kidby said homeowners, slumlords and others who live on the lake “have seen how much land has disappeared: 10, 20 meters in some areas. It’s a piece of land as deep as some people’s allotment lots that’s gone now, that’s in the lake.”

See the map here.

To build the map, the authority spent three years consulting geoscientists and engineers, collecting detailed elevation information and wave modeling.

Putting a price on shoreline hazard

Reactions from people on the coast have been mixed, Huber-Kidby said.

Some landowners and cottagers are looking for ways to slow down erosion and ask, “What can I plant, how can I build, what can I do to make this not a problem for me in the future?”

Others are “rather passive,” he said, acknowledging that it’s a dynamic coastline moving inland.

“They just say, ‘Well, based on the maps, it looks like I’ve got another 20 years, 30 years, maybe another 50 years with my cottage. That’s all.

“The best thing is actually to get out of danger,” he said. “In an ideal scenario, there’s room for those cottages to just move back in. As the land disappears into the lake, there’s room to literally pick up the cottage and move it back, out of that danger.”

Investigators are trying to pin down the dollar value of what’s at risk. They aggregate property values ​​for land, buildings and infrastructure to get a picture of the expected tens of millions of dollars within the erosion hazard line.

Water level up, lake ice down

The bluffs along southeastern Lake Huron — one of the areas most likely to be hit hardest by rapid erosion — were created thousands of years ago by glaciers and are slowly being eroded by waves, said Chris Houser, vice president for research and innovation at the university. from Windsor.

“We’re just at this point where we’ve developed on them. As they accelerate, we’ll see that damage.”

Those waves are more likely to pound the shoreline for two reasons:

• Rising water brings waves closer to land, leading to flooding and property damage. As the water level rises, Huber-Kidby said, “All expectations are that new records will be set in the future.”
• Lake ice: “Each year we see less and less lake ice that usually protects the shoreline from winter storms,” ​​Houser said.

Huber-Kidby agrees.

“In the winter, when they have that natural protection less of the year, they get hit by more waves. They get hit by more energy — and as a result, they erode more,” he said.

Bringing new voices to the table

With an improved map and updated data, Huber-Kidby hopes the region will be better equipped to make good decisions.

While municipalities and cottage associations have traditionally been considered stakeholders, he said the conservation authority is trying to bring new voices to the table by reaching out to indigenous communities, educators, researchers, engineers and other groups.

“A number of families have been around for several generations,” so could have valuable input, Huber-Kidby said.

“They’re on these shores. They’ve seen these storms. They’re really at the forefront of seeing these impacts.”

Getting a snapshot of a possible rapid bluff retreat is a priority, while other conservation authorities are reaching out to Maitland Valley to replicate their modeling.

Huber-Kidby said the difference had to do with predicting climate change.

“It’s a real part of the mapping; it affects where lines are on the map. Historically, climate change was there, but a paragraph at the end of a report — it’s not good enough anymore.”

For now, a card in hand can aid in the path forward.

“These systems are dynamic,” says Houser, who studies changes on Lake Erie’s north shore to get a snapshot of how sediment moves.

“So we can harden the coastline, we can plant dune grass, we can come up with nature-based solutions. But it will still change.

“Are the lakes going to increase because there’s going to be more precipitation? Are the lakes going to decrease because we’re going into an ever-increasing drought? We don’t know,” he said.

“What we should be able to do is say, ‘This is a very dynamic coast. It will change in the future.’ We need to make sure that we’re … working on that coast, that we’re living on that coast, in a way that recognizes that change.