The protective role of natural and engineered defence systems in coastal hazards

Prepared for the State of Hawai'i and the Kaulunani Urban and Community Forestry Program of the Department of Land and Natural Resources:

This report reviews the role of vegetation and engineered defenses for protecting people against tsunamis, hurricanes, cyclones and typhoons. It focuses on the quantitative studies that have been undertaken to assess the effectiveness of natural defenses such as coastal vegetation, including sand dunes upon which much coastal vegetation grows, for protecting human communities from tsunami wave(s). The majority of the work focuses on mangroves.

The report provides a broad literature review of historic and empirical evidence for a protective role of vegetation as a natural defence system against coastal hazards. The background literature on various type of engineered defence systems designed to protect the coast against coastal hazards and their performance in historical cases are also reviewed. The report also provides a review of the storm surge effects of hurricanes, cyclones and typhoons, rather than the wind effects.