How P.E.I. is exploring new ways to protect the coastline from future Fionas

With record damage to P.E.I.'s coastline in the wake of post-tropical storm Fiona, the provincial government and researchers are looking at new ways of protecting the Island shoreline.

One project is showing promise: offshore reefs, installed first at the Souris causeway and in 2022, at the West Point lighthouse.

They are part of a monitoring project by UPEI's school of climate change and adaptation that istracking erosion at eight key infrastructure sites across Prince Edward Island.

A drone flies over each site twice a year, to record any changes to the shoreline, and in some cases, how armouring and other shoreline protection measures are holding up from year to year.

"I think a large part of this is the province investing money in different armouring solutions for infrastructure. So whether that's protecting a road or a bridge, for example," said drone pilot Andy MacDonald.

"By flying these sites twice a year, we're able to get a good idea of how the infrastructure is holding up, and maybe any changes that need to happen moving forward."

The other sites are: Cape Traverse, Cedar Dunes Provincial Park andWest Point lighthouse, Crowbush golf course, Grand Tracadie beach, Jacques Cartier Provincial Park, Miminegash harbour, and the Panmure Island causeway.

Most of themhave some form of hard armouring, or rock wall protection.

"We've seen a lot of changes, especially following Fiona, and that's a good learning opportunity for this. We're going to experience more of these extreme weather events," said UPEI master's student Catherine Kennedy.

"We've seen very large losses, and I think we're learning a lot of lessons about how we should be moving forward, and where we should, or should not, be considering these hard armoury installations."

'Mitigating the inevitable'

Kennedy said the UPEI research is showing the hard armouring does not stand up to severe weather events such as Fiona, where in many cases the force of the stormpushed the water over the rock walls.

"Hard armoury really does not protect the coast. It's temporarily mitigating the inevitable really," Kennedy said.

"We really should only see it as temporary, and I think we should really only be prioritizing it in areas with this critical coastal infrastructure, so areas with wharves and bridges."

"Then in areas where it's more private property or parks, we wouldn't really be recommending the use of these ongoing."

Offshore reefs

Two of the infrastructure sites are protected by offshore reefs, which Kennedy said are showing interesting results.

She called the two artificial reefs installed at the Souris causeway in 2018 a "hybrid option,"because they use large piles of rocks engineered in place, but they are sandstone, so are more natural than imported rock.

"We've seen the beach building back in that area," Kennedy said.

"It's certainly encouraging to see that, and that's an important place. It does have a bridge that is critical infrastructure."

Following the success in Souris, six intertidal reefs were installed in 2022 along the shoreline in front of the West Point lighthouse and Cedar Dunes Provincial Park.

Brian Thompson, a director with the province's Department of Transportation and Infrastructure, said it's important to explore new ways of protecting the shoreline, especially in the wake of increasing storms, such as Fiona.

He said the intertidal reefs, when positioned properly and built at the right separation and distances from the shore and from each other, slow down the current and allowsediment to drop out of the water column, and build up the beach.

These projects do cost a lot of money, but our province and our communities are worth a lot of money. Brian Thompson, Department of Transportation and Infrastructure

Thompson said the province also uses hard armouring in certain situations, andrecently installed 750 metres of hard armouring along a section of road at North Cape.

"At some locations, there's no opportunity to build the shoreline out towardan intertidal reef. We may have infrastructure like a roadway that parallels a cliff, and in that case, hard armouring is the best option," Thompson said.

"It's a known engineering approach that has proven itself worthy over time, and we're very comfortable in using that in appropriate locations."

Thompson said his department is working on several new shoreline protection projects this winter, including at the Panmure Island causeway, more work at West Point and a new saltwater marsh project at the Souris causeway.

"We're going to keep learning as time goes on, and we're not going to be afraid to use innovative engineering approaches to address climate change challenges," Thompson said.

"These projects do cost a lot of money, but our province and our communities are worth a lot of money."