As the climate continues to change, rising seas must be met with adaptive management strategies to protect coastal communities. Nature-based solutions, such as the preservation and restoration of reefs and marshes, have been shown to reduce flooding and storm surge intensity. These coastal habitats can offer more long-term and cost-effective management than traditional methods such as seawalls. However, there has not yet been a quantitative assessment of such nature-based solutions specific to the California coastline. The San Francisco Bay shoreline, which will account for approximately two-thirds of all flooding impacts in California, faces a particular need to address this growing concern.
This project aimed to design and test a model, using available data and observations, to depict wave action and rising water levels along the San Francisco Bay coastline. This model was used to assess how well the existing tidal marshes and mudflats reduce the impacts of flooding as well as to identify and assess future options for flood protection in other areas of the San Francisco Bay.
The researchers found dense vegetation is effective in reducing waves and flooding, which means it should be a high priority in nature-based flood defenses. Marshes with higher elevation relative to sea level would be the most effective in reducing waves and flooding.
This data will be used to quantify the economic value of preserving these coastal habitats, which can aid future coastal planning in San Francisco and the broader west coast. As coastal California communities continue to seek effective and affordable solutions for coastal resilience, such models and data will be beneficial in suggesting guidelines for successful flood reduction solutions.