摘要：Flash-flood is considered as one of the most common natural disasters in Grenada, a tropical small state island in Caribbean Island.Grenada has several areas which are susceptible to flooding.One of them is Gouyave town which is located in the north-west of Grenada.Its land-use types are highly dominated by green areas, especially in the upper-part of the region.The built-up areas can only be found in the lower-part of Gouyave watershed, near the coastal area.However, there were many land conversions from natural land-use types into built-up areas in the upper-part region.They affected the decrease of water infiltration and the increase of potential run-off, making these areas susceptible to flash-flood.In addition, it is also influenced by the phenomenon of climate change.Changes in extreme temperature increase higher potential of hurricanes or wind-storm, directly related to the potential escalation of flash-flood.To develop effective mitigation strategies, understanding the behavior of flash-flood is required.The purpose of this paper was to observe the behavior of flashflood in Gouyave watershed in various return periods using OpenLISEM software.It was used to develop and analyse the flash-flood characteristics.The result showed that the climatic condition (rainfall intensity) and land-use are influential to the flash-flood event.Flash-flood occurs in 35 and 100 years return period.Flash-flood inundates Gouyave’s area in long duration, with below 1 m flood depth.The flood propagation time is slow.This condition is also influenced by the narrower and longer of Gouyave basin shape.To develop flash-flood reduction strategies, the overall understanding of flash-flood behavior is important.If the mitigation strategy is adapted to their behavior, the implementation will be more optimum.
其他摘要：Flash-flood is considered as one of the most common natural disasters in Grenada, a tropical small state island in Caribbean Island. Grenada has several areas which are susceptible to flooding. One of them is Gouyave town which is located in the north-west of Grenada. Its land-use types are highly dominated by green areas, especially in the upper-part of the region. The built-up areas can only be found in the lower-part of Gouyave watershed, near the coastal area. However, there were many land conversions from natural land-use types into built-up areas in the upper-part region. They affected the decrease of water infiltration and the increase of potential run-off, making these areas susceptible to flash-flood. In addition, it is also influenced by the phenomenon of climate change. Changes in extreme temperature increase higher potential of hurricanes or wind-storm, directly related to the potential escalation of flash-flood. To develop effective mitigation strategies, understanding the behavior of flash-flood is required. The purpose of this paper was to observe the behavior of flash-flood in Gouyave watershed in various return periods using OpenLISEM software. It was used to develop and analyse the flash-flood characteristics. The result showed that the climatic condition (rainfall intensity) and land-use are influential to the flash-flood event. Flash-flood occurs in 35 and 100 years return period. Flash-flood inundates Gouyave’s area in long duration, with below 1 m flood depth. The flood propagation time is slow. This condition is also influenced by the narrower and longer of Gouyave basin shape. To develop flash-flood reduction strategies, the overall understanding of flash-flood behavior is important. If the mitigation strategy is adapted to their behavior, the implementation will be more optimum.
