Landslide susceptibility and hazard zoning in a portion of the Three Gorges Area, China

Since the water storage of the Three Gorges Reservoir (China) in June 2003, a number of new landslides occurred and existing landslides were reactivated over the slopes facing the reservoir. As a consequence, along with the process of immigration and development, landslides bring significant disadvantage to the reservoir and navigation and cause consequences to people’s life and property. Indeed, landslide susceptibility and hazard assessment is a fundamental step to properly manage the landslide risk, namely the most efficient way to reduce future damages and loss of lives caused by landslides. However, in China standard procedures for susceptibility and hazard zoning maps are currently lacking; this introduces a relevant constraint for risk mitigation measures. JTC-1, the Joint Technical Committee on Landslides and Engineered Slopes, filled this gap on 2008 by proposing the “Guidelines for Landslide Susceptibility, Hazard and Risk Zoning for land-use planning” which provide definitions, terminology and international standards for types, scales, levels and methods of zoning. In this paper, the applicability of landslide susceptibility and hazard zoning at different levels is tested in the densely urbanized area of Wanzhou that belongs to the Three Gorges Area.