Communities can adapt to sea level rise using a variety of solutions. The challenge is to implement ideas that are appropriate for the community, and are designed with community involvement. When the public is given the knowledge of basic adaptation concepts, they are empowered to be involved in the process. They are empowered to re-imagine their communities and tell stories of adaptation.
Considerable effort has been taken by the Provincial government, regional bodies, and local municipalities to define steps towards adaptation. The first step involves defining the risks associated with sea level rise. This involves modeling coastal hazards, determining overland flooding potential, and finally, estimating the direct and indirect social, economic and environmental risks. This step is typically led by governments and conducted by experts with public input. Public engagement is required to communicate risks to the greater public – storytelling is an accessible approach for this task.
The BC Sea Level Rise Primer identifies four broad approaches to adaptation: protect, accommodate, retreat, and avoid. All four approaches may be used together in a variety of ways to offer protection to coastal communities. A brief description of each approach is provided below:
1. Protect - Maintain the existing landscape and land use through structural measures. This may be appropriate depending on what's at risk, but it can also be very costly and can interrupt community landscapes and ecosystems.
2. Accommodate - Continue coastal living but strike a balance between land use and structural and non-structural measures to
achieve solutions that make landscapes resilient to future water levels.
3. Retreat - Execute strategic decisions to abandon and/or relocate assets and land use from coastal hazard areas.
4. Avoid - Plan to minimize development or certain land uses in coastal hazard areas.
These approaches may be translated into a variety of designs, tools, and planning measures for communities to protect and accommodate themselves in the future. After sea level rise risks are defined and communicated using hazard and risk maps, adaptation concepts can be considered and brought into the storytelling process. Brief descriptions are given below of the range of adaptation approaches and solutions.
Primary protection systems
Primary flood protection concepts provide the first line of defense against some or all coastal hazards, e.g. sea level, tide, storm surge, and wave effects. Concepts range widely from traditional earthen dikes to natural beach/dune protection. These concepts are not limited to only engineered structures and can include staged raising of the landscape or affecting land use to allow certain areas to flood during extreme events.
Communities can imagine incorporating primary protection concepts through:
Developing coastal trail networks with raised landscapes and bio-engineered erosion protection and wave energy dissipation;
Staged raising of coastal roads and adjacent buildings;
Coastal public/park spaces without permanent structures that would be closed and flooded during extreme tidal storm surge events; and
Traditional dikes and sea walls in areas where accommodation is not appropriate and business assets need to be protected.
Large scale engineered barriers, such as popular examples from the Netherlands and the United Kingdom, are likely not appropriate for the social, environmental, political, and economic contexts of our region and would likely provide less opportunities for communities to thrive through adaptation. These concepts should be considered very carefully if deemed necessary.
Secondary protection systems
Dikes may breach, sea walls will crack, and the big storm might be bigger than we estimated. Secondary protection systems provide protection against overland flooding on streets and near buildings to minimize risks. Secondary concepts are generally focused at neighbourhood and house/building scales. The purpose of these concepts are to minimize risks from floodplain waters which in inland communities may be shallow and slow moving or deep and fast near the coastal/riverfront communities.
These concepts can involve:
traditional tools such as variable Flood Construction Levels (FCLs) which raise structures on fill;
adaptive methods such as wet floodproofing which protects structures from floodwater damage by allowing water around the structure;
collaborative landscape planning and design where community features such as roads, medians, and sidewalks can define overland flood paths away from critical facilities;
Integrated community development plans that take advantage of planned in-fills (such as pre-construction site loading) to raise landscapes.
Redundancies & resilient design
Resilient systems have redundancies that provide additional protection when things don’t behave as expected. Redundancies with respect to adaptation to sea level rise will involve site specific considerations which should be easy to implement and empower people to further protect themselves. Temporary barriers (especially passive ones that raise by themselves) could provide redundant protection for specific facilities or for those who feel they are especially vulnerable.
New designs will also be required for future homes and buildings so that structures may be adaptive to changes in streetscape elevation. For example, in an urban context, the transition of streetscape elevations over time will need to be considered as streetscape elevation may change to act as an internal dam network. In response to this transition multi-family dwellings may be required to have high ceilings on the ground floor. The extra height would ensure that if the internal floor was raised to accommodate access to a raised streetscape the space would still be habitable.
Policy & regulation
Most local, regional, provincial policies and regulations that dictate how our communities are built were written in a world before adaptation to sea level rise was considered. Policy and regulatory review is a slow process; however, it is necessary and must be sped up to prevent maladaptation in our communities.
The Province of British Columbia is taking steps to update flood hazard guidelines but a closer look at the Local Government Act, Community Charter, Vancouver Charter, BC Building Code, Strata Property Act, Environmental Management Act, local Official Community Plans, Zoning Bylaws and Subdivision and Standards Bylaws is necessary. Policies, bylaws, and regulations on form and character, height, energy use, and industrial design need to be re-examined so that our future communities are low carbon and resilient to the impacts of sea level rise.
Emergency planning & response
Adapting to sea level rise will not just involve technical responses. Social planning in the form of emergency planning for families, vulnerable populations, neighbourhoods, business and industry, and farmers will also be required.
Robust emergency planning and response programs will enhance social and economic resilience within communities. Emergency planning will also mitigate environmental incidents should floodwaters overwhelm coastal business and industry. Emergency planning will need to consider and support:
the lead up to an anticipated event through storm surge forecasting, communication, education, evacuation signage, and industrial facility shutdown procedures;
responses during the flood event. Information and communication about closed roads and areas as well as evacuation procedures in extreme instances may be needed; and
post-emergency actions such as the restoration of services, assessment of damage, and the assessment of emergency planning actions and coastal infrastructure performance.