Coastal inundation multi-hazard analysis for a construction site in Malaysia

Establishment of new manufacturing sites in high-technology industries requires considerable investments. These investments need to be safeguarded against the impacts of natural hazards. The March 2011 Tohoku earthquake and tsunami highlighted the tremendous impacts of cascading hazards and emphasised the importance of hazard and risk assessment in the early stages of site selection. A screening study of coastal inundation due to multiple hazards was performed for a potential manufacturing plant at the Batu Kawan Industrial Park in Penang state, Malaysia. The analysis accounted for river floods, rainfall and flash floods, cyclones, tides, storm surges, sea-level rise, and tsunamis. Natural hazards not related to inundation, such as earthquakes and volcanoes, were also briefly evaluated. Where relevant data were available, the hazards were assessed quantitatively. Otherwise, they were assessed qualitatively. The effects of climate changes were discussed for temperature and rainfall and for sea-level rise. The proposed development site elevation of 2.60 m LSD (Land Survey Data Level; 30 cm above mean sea level) will probably be reached by both the 100-year flood and the 100-year combined tide and storm surge. With a well-engineered drainage system the flooding risk is low, but in this low-lying area coincidence with a storm surge or high tide will aggravate the flooding situation. Sea-level rise over the next 100 years for the region is assumed to be less than 0.55 m. The relative levels for the other hazards were found to be lower. There is obviously significant uncertainty associated with the estimated hazard at the return periods considered for design. A further comparison of the various hazard levels is not meaningful without considering also the consequences (i.e. the risk)