January storms claimed more than a metre of shoreline in Cavendish

Parts of P.E.I. National Park lost more than year's worth of erosion to its shoreline after just two major winter storms this month, Parks Canada says.

Garrett Mombourquette, an acting resource conservation manager with the national park, said there was impact across the park's roughly 65-kilometre shoreline, but was most noticeable in places like Cavendish Campground where between one and two metres of shoreline was lost.

"On average, in Prince Edward Island National Park from 2010 to 2020, we observed an annual rate of erosion in our till substrate of 1.18 metres per year, so we're looking at about one average year's worth of erosion just from these two storms," he said.

There was also some erosion on Robinson's Island, some downed trees on park trails and other damage to infrastructure — including a lost handrail at Stanhope main beach and a downed light pole at Stanhope campground.

Coastal erosion is a natural process and while it is "remarkable," it's not surprising, Mombourquette said. 

"Erosion is common and something that we're used to adapting to and monitoring in Prince Edward Island National Park. Of course, with the reduction of near-shore ice in recent years, we're noticing an increasing proportion of coastal erosion during the winter months," he said.

Mombourquette said park officials last winter observed the fewest days with near-shore ice present since they began monitoring it in 2014. 

"Wave energy that comes from these storms is slowed down or attenuated, and so we typically like to see near-shore ice be present because it acts as a natural barrier that prevents the accelerating rate of erosion," he said.

As the rate of erosion accelerates, so too will the need to consider relocating or retreating coastal assets, he said.

"Over time, we'll get a better sense and a clearer picture of what the impacts of climate change will be."