Flood Risk Management in Cities

While bayside areas, which enjoy coastal natural environment, amenity, scenic landscapes, and so on, are typically attractive residential areas, they are very often vulnerable to flooding too. Unfortunately, flood risk is gradually increasing in Asian cities. In particular, the Tokyo metropolitan area is known as a high-risk metropolis. Building flood risk resilience while keeping the attractiveness of the bayside area is a critical issue in Tokyo. The objective of this study is to analyze the trade-off between benefits from the ocean and flood risk as a first step to increase urban resilience. To quantify the trade-off, this study uses the hedonic approach. We first review related hedonic studies and discuss which hedonic model is suitable to apply in our analysis. Subsequently, we perform a hedonic analysis of condominium prices and quantify the benefits from ocean-related variables, including ocean view and proximity to the ocean, and the negative effects from the flood risk. Here, a spatial additive multilevel model is used. The analysis results reveal that the flood risk is highly underestimated while the benefits from the ocean are appropriately evaluated in the target area.