Gorge Coastal Flood Adaptation Strategy

    What is the Gorge Coastal Flood Adaptation Strategy?

    The Gorge Coastal Flood Adaptation Strategy is a collaborative project between municipalities that border the Gorge and Portage Inlet. Through the strategy, we will better understand the risks of sea level rise and coastal flooding along the Gorge Waterway and Portage Inlet.  

    The strategy will help guide long-term decision-making about how each municipality adapts to rising water levels to protect people, infrastructure, the shoreline and local ecosystems.

    Who is involved with the Gorge Coastal Flood Adaptation Strategy?

    The project is a partnership between the City of Victoria, the Township of Esquimalt, the Town of View Royal, and the District of Saanich, with support from the Capital Regional District 

    We are also engaging with local First Nations, community-based organizations, businesses and residents.

    What is the project area for the Gorge Coastal Flood Adaptation Strategy?

    The project focuses on the shoreline of the Gorge Waterway and Portage Inlet, a six-kilometre long, narrow arm of marine waters from the Johnson Street Bridge to the end of the Portage Inlet. 

    This shoreline is bordered by the City of Victoria, the District of Saanich, the Town of View Royal and the Township of Esquimalt.  

    What types of adaptation options are the project partners considering for the Gorge Coastal Flood Adaptation Strategy?

    Adaptation options include: 

    • Natural and nature-based solutions (e.g., salt marshes or restored shorelines) 
    • Engineered approaches (e.g., sea walls or raised infrastructure) 
    • Policy and planning tools (e.g., land use regulations or floodplain mapping) 
    • Community-based actions (e.g., emergency preparedness or public education) 

    All options will be evaluated based on community values, technical feasibility and long-term effectiveness.

    What changes or construction will the strategy lead to?

    The Gorge Coastal Flood Adaptation Strategy is a long-term planning process. It will inform future decisions about investments, infrastructure upgrades, environmental work and shoreline management to prepare for a changing climate. Adaptation options may be implemented over time by any of the partner municipalities.

    What other studies will inform the Gorge Coastal Flood Adaptation Strategy?

    In 2021, the Capital Regional District, in collaboration with local municipalities, developed the Capital Region Coastal Flood Inundation Mapping Project to better understand regional impacts from coastal storm flooding due to sea level rise and tsunami events. As part of this project, 222 areas were evaluated for coastal storm flooding for different storm surge and sea level rise scenarios. Coastal flood construction levels were developed for some areas.  

    The Gorge was one of the sites selected for detailed flood modelling due to its low-lying topography, potential susceptibility to coastal flooding and relatively high population density.

    How is this project funded?

    The partner municipalities received $350,000 to develop the Gorge Coastal Flood Adaptation Strategy from the Province of B.C.’s Community Emergency Preparedness Fund, under the Disaster Risk Reduction-Climate Adaptation stream.

Sea Level Rise

    How is sea level rise expected to change in the Gorge and Portage Inlet?

    In the Gorge and Portage Inlet, sea levels are projected to rise by half a metre by 2080 and by one metre by 2110. 

    This will increase the risk of coastal flooding, especially during high tides, storms and heavy rainfall. Some low-lying areas may experience more frequent or severe flooding as a result.

    What areas in the Gorge are at risk from sea level rise?

    Low-lying areas along the shoreline, including parks, roads, homes and businesses may face a higher risk of flooding in the future. Technical studies as part of the strategy are helping identify areas that are most vulnerable based on sea level rise projections, storm surge and other factors.

    In addition to sea level rise, what causes flood risk in the Gorge?

    In addition to sea level rise, flooding in the Gorge can be caused by heavy rainfall, storm surge events, king tides, wind, drainage systems and land elevation. These factors can combine to increase the frequency and severity of flooding events.

    What is sea level rise and what causes it?

    Sea level rise refers to the long-term increase in the average level of the ocean. As the climate warms, melting glaciers and ice sheets, along with the expansion of warmer ocean water and changes in ocean circulation, cause sea levels to rise around the world. Locally, other factors like tides, land elevation, wind and storms also influence sea level rise. 

    A warming planet also generates more frequent and severe storms, increasing the risk of overland flooding from heavy rain events. Storms caused by low atmospheric pressure are also accompanied by winds that push waves and water higher onto land, called storm surge. 

    How has the Capital Regional District been impacted by sea level rise so far?

    Global sea levels are rising, but the Capital Regional District has not seen as much change yet. That’s because the land in our area has been gradually rising. This offsets the effect of rising oceans—at least for now. It’s happening because of two natural processes: 

    • Tectonic uplift, caused by the movement of the Earth’s crust along the edges of tectonic plates. 
    • Post-glacial rebound, the slow rise of land that was once compressed under the weight of massive glaciers during the last ice age, about 20,000 years ago.

    But climate change is making sea levels rise faster around the world. Over time, the ocean will likely rise more quickly than the land — which means higher risk of flooding along the coast, including in the Gorge Waterway.

    How is local sea level rise calculated?

    Experts use detailed elevation maps of the shoreline and combine them with global sea level rise projections based on climate models. They also consider high tides, extreme storm surges, and how much the land is rising due to tectonic forces and post-glacial rebound. Together, this information helps create maps that show where flooding may happen in the future so communities can plan and reduce risk.