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

Abstract

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 Qu ebec, 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.

Coastal Vulnerability to Erosion Using a Multi-Criteria Index: A Case Study of the Xiamen Coast

“…Indexes of coastal forcing (CF) consist of [30] significant wave height and storms. Indexes of coastal infrastructure (CI) include [5,58,59] the values of roads, values of buildings and population activity. Indexes of disaster reduction (DR) comprise [24] fiscal revenue and GDP per capita.…”

“…This study uses this range to identify potential losses due to coastal erosion. Previous studies [57,58,[61][62][63] have indicated that the range of erosion is the erosion rate multiplied by time. The average rate of coastal erosion in Xiamen is 1 m/a [51].…”

“…(1) Coastal geomorphology: Coastal geomorphology refers to the surface type of a coastal zone. Different surface types in coastal zones respond differently to coastal erosion; for example, sandy coasts are more vulnerable to erosion than rocky coasts [6,21,30,58]. The surface types of coastal zones are divided into two categories, namely, natural surface types (rocky coasts, gravel coasts and sandy coasts) and artificial surface types (seawall, port and revetment).…”

“…The total value is equal to the length of the evaluation unit multiplied by its relative value. 7Values of roads and buildings: Roads and buildings are important components of coastal infrastructure [5,58,59,69], and coastal erosion can damage roads and buildings.…”

“…(1) The changes in tidal range and relative sea level rise in the study area are very small; thus, they cannot be used to differentiate among variations in evaluation units. (2) The extent of possible erosion effects must be determined, as according to previous studies [57,58,[61][62][63], the range that may be affected by coastal erosion extends 100 m from the coastline landward. (3) Due to the low resolution of the road and building space in previous studies [30,74], this study uses eCognition Developer 8.7 to extract the GF-2 raster to obtain high-resolution data and the big data Baidu population density heat map to obtain high-resolution population activity density data.…”