The escalating challenge of coastal flooding in low-lying areas like San Francisco Bay demands new solutions. As sea levels rise and storms intensify, traditional levees face growing challenges. A new study, however, points to promising nature-based 'horizontal levees'.
These hybrid structures, composed of wetland buffers that slope out before conventional levees, can reduce floodwater overtopping by up to 30%. They also support valuable marsh habitat, offering dual benefits for coastal flood risk reduction.
Unlike conventional levees, horizontal levees feature a gradual, vegetated slope. This natural buffer efficiently absorbs wave energy, reducing pressure on the main levee. A hydrodynamic model, simulating San Francisco Bay storms, confirmed their effectiveness.
The study emphasizes that broader, gently sloped wetland areas are most effective for wave attenuation. Beyond mitigating coastal flooding, these systems offer numerous co-benefits: filtering pollutants, supporting wildlife, and serving as carbon sinks. San Francisco Bay's unique landscape is an ideal testing ground for this innovative solution.
