Two sandstone reefs installed by the Prince Edward Island government along the Souris causeway are having their intended effect. The offshore breakwaters, or intertidal reefs, are designed to protect the causeway—the main route into town—and the picturesque shoreline from the punishing effects of climate change and storm surge events.
Souris residents are excited to see sand building-up along the beach area instead of leaving due to erosion, reports the province. The intertidal reefs were a part of a second phase of a project to protect the shoreline. During the first phase, a seawall was created to protect the beach and causeway.
“Some locations are more challenging and susceptible to the effects of climate change,” said Brian Thompson, director of Land and Environment Division for the Department of Transportation Infrastructure and Energy. “We need to look at alternative, innovative ways to approach these areas.”
The reefs, which were installed last winter as an experimental pilot project at a cost of $115,000, are made of Island sandstone so they blend into the natural environment.
The province worked closely with a local contractor, the town of Souris, as well as the local watershed group, the Souris Wildlife Federation, to study sediment patterns in Colville Bay and come up with the implemented method to reduce coastal erosion that has been threatening the causeway, a critical piece of infrastructure.
The reefs have two functions, providing an obvious barrier between waves and the beach, thus dampening the effects of wave action on the beach and dunes. They also create an area of calmer water on the landward side of the reefs, causing accretion of sand, which should cause the beach to extend over time.
“They are working as we had planned and hoped, it’s quite encouraging,” said Thompson.
The province and Coldwater Consulting intend to apply for an environmental achievement award through the Association of Professional Engineers of Prince Edward Island for the project.
The reefs are working so well, the province is considering similar projects in other areas of the Island.
“We are seeing more frequent and intense storms and, at some locations, alternate engineering approaches need to be explored,” Thompson said. “Everyone, including government, has to find ways to adapt to an ever-changing climate.”