The main objective of this thesis is to assess the effectiveness of Nature-based Solutions in reducing flood risk in the Galveston Bay by means of wave attenuation. The methodology to answer these questions consists of both literature review and numerical modelling. The wave height reducing capabilities of marsh vegetation, seagrass meadows and oyster reefs are described and assessed quantitatively. Their limitations and optimizations strategies are investigated and applied to the Galveston Bay, Texas.