Coastal erosion is a problem throughout Unama'ki (Cape Breton) and will only get worse as climate change progresses. Sea level rise, increasingly powerful storms, and the storm surges that come with them endanger culturally, economically, and ecologically important coastal areas, and even people’s homes.
In Cape Breton, it is not just the Atlantic coast we have to worry about. We also have the Bras d’Or Lakes, an estuary often referred to as an “inland sea,” located in the centre of the island. It has recently been designated a UNESCO Man and the Biosphere Reserve site. This designation acknowledges that human activity is part of the reality of conservation; this could not be truer for the Bras d’Or Lakes. Apart from its importance to industry, economy, and recreation, it has huge cultural significance to the Mi’kmaq people of Unama’ki.
Our project site, Malagawatch, has been a important location for the Mi’kmaq people for thousands of years. It is owned jointly by the five bands, and is home to events and cottages for many people. The shoreline there is receding rapidly, threatening buildings, roads, and shoreline habitat; several large trees have already succumbed to erosion and fallen into the lakes. It is also located next to a cemetery where erosion has threatened to expose graves. As a result, the cemetery was surrounded by armour stone, which has exacerbated erosion on the adjacent, unprotected shoreline.
Our goal is to create a living shoreline to reverse erosion at this site and restore the shoreline of Malagawatch. Living shorelines are a gentler method of erosion control that includes a variety of techniques meant to mimic naturally stable, undisturbed coasts. Common components of living shorelines include planting the shore with a hardy mix of grasses and shrubs, adding biomass to the beach such as coir rolls, and building sills with rock or bags of oyster shells. The plants’ roots stabilize the soil, the biomass protects exposed soil from wind and waves while gradually reducing slope, and sills break up wave energy before the waves reach the shore.
Other methods, including alder mats and bio-logs placed at the toe of the slope, can be used as well. This method not only protects and stabilizes the shoreline but also restores habitat for shoreline species while avoiding the negative impacts of traditional shoreline protection measures (e.g. rock barriers).
It is important that this work is done with the full support and understanding of the Mi'kmaq people who are the stewards of the Lakes and Unama'ki. The first step is to gather knowledge and input from the aboriginal community about Malagwatch, the history of the shoreline there, and how the possible solutions to erosion may be applied in a way that aligns with their values and desires. The first meeting will be held in September to gather this information. Additional information will be gathered on an ongoing basis from this Facebook page and additional future meetings. This will inform the work of a consultant specializing in shoreline preservation and researchers from Cape Breton University who will begin working on the project later. Living shorelines are more ecologically friendly, less costly, and more robust to the effects of climate change than armourstone or bulkheads. Living shoreline projects in New England have been shown to survive high energy storm events better than the popular armour stone and bulkheads, which can be damaged and cause erosion behind them (citation). Many of the materials used (e.g. hay, hardwood cuttings, plants) can be purchased for low cost or harvested near the site. Finally, once living shorelines are established, they become stronger over time with minimal maintenance. Salt marsh plants naturally spread, increasing soil stabilization. They also accumulate sediment, gradually raising the elevation of the site with time. This combats both sea level rise and erosion. The use of oyster bags or segmented rock sills offshore combats wave energy and accumulates sediment without destroying habitat or eliminating wildlife access. Our hope is that this project will preserve the coastal habitat as well as the cultural use and heritage of Malagawatch.