2000

AN OVERVIEW OF HYDROLOGY AND WATER RESOURCES ASSESSMENT AND MANAGEMENT FOR SMALL TROPICAL ISLAND

Tony Falkland, Mohd Nor Mohd Desa
ECOWISE Environmental, ACTEW Corporation, Fyshwick Canberra, Australia
Humid Tropics Centre (HTC) Kuala Lumpur

Small tropical islands are found in the pacific, Indian and Atlantic Oceans and adjacent seas. Many are part of developing countries and have scarce natural land-based resources. In particular, the water resources of islands are often very limited. On many small islands, surface water resources are very limited or non-existent and groundwater resources occur only in the form of thin freshwater lenses. Small tropical islands are vulnerable to natural disasters and the impacts of human activities. Seawater intrusion due to over-pumping of groundwater and pollution of surface and groundwater from population centers, agriculture and other activities are increasing problems. In recent years, applied research projects on selected small tropical islands have helped to obtain much needed local data and information about the hydrology and water balance of selected islands, there is much scope for further work on small islands. This paper presents an overview of the hydrology and water resources. While this has added to our understanding of hydrological processes and the water balance of selected islands, there is much scope for further work on small islands. This paper presents an overview of the hydrology and water resource management of small islands. Factors affecting the occurrence of freshwater resources, and water balance principles are introduced. Water resource assessment methods, examples of appropriate water resource development approaches and selected water management practices are discussed. The impacts of climate change and sea level rise scenarios are examined. Finally, opportunities for research, training, co-operation in the field of small island hydrology are presented.

FLOOD ESTIMATION FOR A SELECTED CATCHMENT IN TIOMAN ISLAND

Mohd Nor M.D.,N.M, Shaffy M.
Humid Tropics Centre (HTC) Kuala Lumpur

Several synthetic methods for flood estimation have appeared in the literature. Apparently all tend to give different results due to the different parameters and variables used to derive the empirical relationships. We applied 6 methods to determine time of concentrations. This time of concentrations are used to determine the design floods of various return periods. It is found that the Modified Snyder Method is most suitable for the Tioman Island. However, further check needs to be carried out using rainfall runoff model.