A New Method for Reclamation Planning in Coastal Areas Based on Vulnerability Assessment to Typhoon Storm Surge Inundation

Abstract:

Rapid urban expansion in mega-cities (cities with populations over 10 million) leads to increased land demand and vulnerability to hazards as often significant numbers of people are economically and social disadvantaged. An effective way to create new flat land for further development is land reclamation and this has reached 511.71 km² in the period of 1990 – 2009 along the Shanghai coast. This, in turn, leads to a potential increase in the vulnerability of the new coastal area to natural hazards. This is typically represented by typhoon storms that have the potential to be the most destructive natural hazard and therefore pose a significant threat to both infrastructure and livelihood in Shanghai. Due to insufficient knowledge of vulnerability of land use to typhoon storms and current planning, the reclaimed land is becoming one of the most vulnerable parts of the coastal low-land. While it is tempting to claim there is an increasing vulnerability to typhoon-inundation in Shanghai, this must be weighed against the socio-political response, where it is likely that city authorities will undertake rational land use planning to protect the reclamation from the inundation, sea level rise, and ground subsidence. Therefore, this research present a new method for reclamation planning based on vulnerability assessment to typhoon- inundation. First, MIKE21 was used to simulate the inundation scenario of two typhoon events in 1997 and 2007 respectively. Then, the vulnerability of 7 land use types with a set of hazard-proxies to these two typhoon inundations was assessed and verified by a new stage-damage curve system. Based on the above vulnerability assessment, this research will provide a planning tool for reclamation along Shanghai coastal area. This work is part of a larger study on the response of vulnerability to land use and land cover change.