Mapping of sections of watercourses whose migration is sensitive to the flow changes anticipated due to climate change
The aim of the project is to develop a method for identifying sections of watercourses whose migration is sensitive to climate change.
Project details
Principal(s) investigator(s)
Context
In Quebec, watercourse migration is a component of river dynamics that is increasingly attracting the attention of the general public, the media and government bodies. Recent regulatory amendments to the Environment Quality Act have made the Ministère de l’Environnement et de la lutte contre les changements climatiques, de la faune et des parcs (MELCCFP) responsible for delineating and approving watercourse migration maps.
Moreover, it has long been recognized that climate change will affect hydrological regimes and watercourse morphological dynamics, yet few resources are currently available to help anticipate likely changes in watercourse migration, which is known as geomorphic sensitivity. The current methods for mapping short-term migration zones (M50) are based on the estimation of average historical migration rates projected for a 50-year period. This approach makes it possible to target and map mobile stretches of river that are partly affected by variability due to climate change, but the identification of those whose migration rates will be altered in a future climate is not currently being considered.
This project is part of the QClim’Eau initiative, a collaboration between the Ministry of the Environment, Climate Change, Wildlife, and Parks (MELCCFP) and Ouranos.
Objective(s)
The aim of the project is to develop a method for identifying river sections in southern Quebec whose migration is sensitive to climate change, and then to map them.
Methodology
The project is based on the extraction of specific power values using geographic information system tools to optimize the analysis for long river corridors, followed by their interpretation in order to anticipate morphodynamic changes linked to disturbances in the hydrosystem.
The project’s phases are as follows:
Identification of specific power thresholds over which watercourses are mobile in several physiographic contexts in Quebec
Use of these thresholds applied to current and future hydrological conditions to determine anticipated changes in watercourse migration in southern Quebec
Large-scale specific power calculations for current conditions and future climate conditions for recurring morphogenetic flows
Mapping of the distribution of specific power values for 3 to 5 catchments
Development of recommendations on the mapping approach to be used when changes in mobility are anticipated
Expected results
The project will contribute to the development of the MELCCFP’s mapping of watercourse migration zones by proposing adjustments and considerations based on the nature of anticipated mobility changes in future climates. The mapping produced will also be relevant to the production of migration warnings by the Ministère des Transports et de la mobilité durable.
Benefits for adaptation
Benefits for adaptation
Improved mapping of flood zones and migration zones, taking the impacts of climate change on watercourse migration into account, will enable more appropriate land use planning and better risk prevention.
Funding
716200
