A comprehensive review of compound inundation models in low-gradient coastal watersheds

Extreme coastal flooding poses a major threat to human life and infrastructure. Low-gradient coastal watersheds can be vulnerable to flooding from both intense rainfall and storm surge. Here we present a comprehensive review of the most recent studies that quantify extreme flooding using variations of a compound inundation model. A compound inundation model may consist of different numerical models, observed data, and/or a combination of these. The definitions, advantages, and limitations of each joining technique are discussed with the goal of enabling and focusing subsequent research. Future investigation should focus on the development of a tight-coupling procedure that can accurately represent the complex physical interactions between storm surge and rainfall-runoff. A more accurate compound flood forecast tool can help decision-makers, stakeholders and authorities converge on better coastal resiliency measures that can potentially save human lives, aid in the design of structures and communities, and decrease property damage.