Shoreline erosion and relative sea level rise are increasing the risk of flooding and storm damage to Highway 2 as it approaches the Town of Souris in PEI. Climate change with the associated rising sea levels, reduced ice cover and changing storm patterns threaten to exacerbate this problem. The risk of flooding and temporary closure of Highway 2 at this location will increase over time. These considerations, along with the erosion and inundation observed during the 2016 storms, led to a decision by the Province to protect the highway. With increasing concern over the effects of climate change, there is an increased interest in developing durable, resilient shore protection works. Various approaches have been used to protect the causeway infrastructure including Gabion baskets, armourstone, and a timber crib and steel pile wall. These efforts have supported local economic growth, such as the expansion of the Souris Beach Gateway Park, new commercial outlets and a playground. Traditional armouring approaches, however, require periodic and sometimes costly maintenance over the long term. In some situations, this armouring approach can also accelerate erosion and deplete a beach of valuable sand. With that in mind, a project to implement a naturalized infrastructure installation in PEI was initiated in 2018. Two intertidal reefs were designed by the provincial government to increase the resilience of the beach and dune system while protecting the causeway and park infrastructure
The Town of Souris, Prince Edward Island (PEI), is a coastal community that is dependent on tourism and fishing. Similar to PEI’s other coastal communities, Souris has been forced to deal with the storms and wave action that have been eroding its sandstone shoreline and threatening its infrastructure. The causeway into the town is a vital conduit for the local economy and is a popular beach for tourists. Climate change with the associated rising sea levels, reduced ice cover, and changing storm patterns threaten to exacerbate this problem. In order to improve protection of the PEI portion of the Trans-Canada Highway (Hwy 2), PEI Transportation Infrastructure and Energy (PEI-TIE) worked with Coldwater Consulting Ltd. to develop and construct a two-part shore protection scheme that combined hard protection for the highway infrastructure with beach restoration works that would improve the resilience of the beach and dune system: 1. A timber/piled seawall was constructed parallel to Highway 2. This seawall allows for protection of the highway, while also extending the existing promenade along the top of the seawall. The wall was set back from the beach face to allow adequate space for beach restoration. 2. Dune restoration and shoreline stabilization works were undertaken to restore and strengthen the existing sand beach – dune system. The beach restoration works included the construction of two inter-tidal reefs. This is the first time that inter-tidal reefs have been used on the Island. An example of ‘building with nature’, the sandstone reef structures provide two primary functions: wave attenuation, dampening the effects of storm waves on the beach area and highway infrastructure; and, creating an area of calmer water on the landward side of the reefs where sand that is moving along the shore area will slow down and deposit and, over time, accumulate and cause the beach to grow / extend offshore towards the reefs. The result is increased beach width and protection of the dunes and coastal / highway infrastructure.