Development of a GIS coastal land-use planning tool for coastal erosion adaptation based on the exposure of buildings and infrastructure to coastal erosion, Québec, Canada

This study presents the development of a geographic information system (GIS) land-use planning tool for coastal areas based on the calculated exposure to coastal erosion of buildings and infrastructure. Responding to the needs of land-use planners, who are involved in the project from the beginning, this tool facilitates identification of adaptation solutions based on coastal sensitivity to erosion. All buildings, roads, railways, aqueducts, sewer systems, hiking trails and bicycle routes were mapped at high resolution, and an exposure value was assigned to each for seven time horizons between 2015 and 2100. The calculations were based on three parameters: (1) the distance between the structure and the shoreline or coastline; (2) the most likely shoreline or coastline migration rate for each coastal geomorphology behaviour unit (CGBU); and (3) the maximum event retreat measured during a storm for each type of coast. This method was applied to Baie des Chaleurs in Québec, Canada. The area comprises 11 municipalities with a total of 105 km of coast. The approach not only produces current and future portraits of building and infrastructure exposed to erosion, but also provides an original land-use planning and intervention tool for coastal areas.