| Résumé | (Sommaire disponible en anglais seulement)
Climate change is here, increasing global loss of life and property damage as weather patterns change. We now know that with climate change comes
rising seas -- and that this sea level rise will dramatically affect Canada's southern coastal communities.1 These communities will require resilience and adaptive capacity to ensure their long-term sustainability.
Coastal hazards associated with
sea level rise include:
- Coastal inundation and reduced drainage capacity;
- Coastal erosion;
- Changes to coastal habitats and loss of wetlands such as salt marshes;
- Reduction in coastal sea ice; and
- More frequent and intense
storms, storm surge and wave action.
This Primer provides an introduction to past and future sea level, an overview of four different adaptation strategies, a recommended framework for decision making and finally a total of 21 adaptation tools to
support local adaptation action.
The B.C. Ministry of the Environment commissioned the preparation of this Sea Level Rise Adaptation Primer for Canada's Atlantic and Pacific coasts. Although this Primer was prepared in B.C., legislative
provisions, policies and local government applications discussed in this Primer include B.C., southern Quebec and the Atlantic coasts of New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador. Coastal communities along Hudson Bay
and in the Arctic face a different set of vulnerabilities and were not considered within the context of this research.
Adaptation strategies to sea level rise can be grouped as follows:
Protect is a reactive strategy to protect people, property
and infrastructure from sea level rise and is typically the first response considered. Protecting the coastline through structural mechanisms such as dikes, seawalls and groynes has been the traditional approach to dealing with sea level rise in many
parts of the world. With increasing sea level rise and coastal vulnerability, this strategy may be prohibitively expensive and have limited long-term effectiveness in highly vulnerable locations.
Accommodate is an adaptive strategy that allows
continued occupation of coastal areas while changes are made to human activities and/or infrastructure to adapt to sea level rise. Accommodation can also involve retrofitting a building or making it more resilient to the consequences of sea level
rise. Other accommodation measures may include liability reduction, such as a covenant indemnifying governments from the consequences of coastal hazards regardless of protection works undertaken.
Retreat or Managed Retreat refers to any strategic
decision to withdraw, relocate or abandon private or public assets at risk due to sea level rise and associated coastal hazards. Retreat is an adaptive strategy to limit the use of structural protection, discourage development in areas subject to sea
level rise, and plan for the eventual relocation of buildings and infrastructure to areas with no risk or lesser risk. Avoid involves ensuring new development does not take place in areas subject to coastal hazards associated with sea level rise or
where the risk is low at present but will increase over time. This may involve identifying future 'no build' areas within local government planning documents. A wide range of planning tools may be involved, leading to a decision to avoid development
in areas subject to moderate to high risk. An avoid strategy may involve land acquisition or the transfer of development potential to areas of lower risk.
These adaptation strategies are not mutually exclusive. Two or more strategies may be
applied in different geographic areas by the same local government. The most appropriate strategy for a geographic area may also change over time. To implement these strategies, a wide range of adaptation tools are available.
Adaptation tools
included in this Primer tools should be considered in the context of information gathering, public education and community engagement, all crucial to informed decision-making processes within our democratic system.
Planning tools in this Primer
include local government growth management objectives and policies, mapping of potential coastal hazards, risk management and emergency preparedness.
Regulatory tools include the regulation of subdivision, land use and buildings. These regulatory
tools are generally prescribed by legislation and require the approval of a decisionmaker or 'gatekeeper' responsible for the protection of the public interest.
Land use change or restriction tools focus on the change or restriction of land use
other than through the regulatory functions noted above. Some of these tools are at the disposal of local government and others may be undertaken by private landowners or community groups in order to achieve local government goals.
Structural
tools consist of physical structures on land or in water to protect land and buildings from coastal hazards. A wide range of hard protection and armouring fit in this category.
Non-structural or soft armouring measures include the creation or
restoration of wetlands, building sand dunes, or rehabilitation and beach nourishment. Both sand dunes and beaches are naturally occurring features, created by the interaction of wind, waves and sediment. They serve to dissipate the energy of storm
surges and wave action. These natural features can be mimicked or recreated to provide an adaptive buffer to sea level rise.
Several of these tools are interdependent and should be used in combination. While structural and nonstructural
adaptation tools may appear to represent polar opposites, combining them and creating hybrid shoreline protection systems may result in synergies and cumulative benefits. As one example, living shorelines are hybrid protection systems that use
coastal ecosystems to reduce erosion risk and optimize natural shoreline functions.
An analysis of each adaptation tool is provided in this Primer. The analysis includes a description of the tool, a discussion of implementation methods and an
identification of the enabling legislation, where applicable. Advantages and disadvantages of the tool are also examined using a 'triple bottom line' approach.
In addition to tools available to local governments, insurance and emergency
management are also adaptation tools included in the Primer. Overland flood insurance for residential development, while not a tool available to the public or any level of government in Canada, is discussed as it plays a major role in all other G8
countries. Emergency management is a tool available to communities across Canada, but responsibility for emergency management is shared with senior governments.
Also included in the Primer are appendices consisting of: acronyms; a glossary of
terms; a spreadsheet profiling the adaptation tools; legislative matrices in B.C. and Atlantic Canada; and a wide range of municipal policies and bylaws in Atlantic Canada. The Primer concludes with both an annotated bibliography and a bibliography
organized into four geographical areas: Canada, Quebec, U.S.A., and other international areas. |