Impacts of Flood Simulation in 3D and SWAT Environment of Terengganu River Catchment

Flood is a natural hazard influenced by climatic and anthropogenic factors. The Terengganu River
catchment is located near the South China Sea has been flooding during heavy monsoon season with
strong rain-bearing winds to the interior coastal zones of Kuala Terengganu. The ArcSWAT2012
extension of ArcGIS10.3 and ArcScene10.3 has been used to design 3D models simulations to
predict flood risk event through the stream flow and elevation data derived from ASTER DEM. The
Hydrologic Response Units (HRUs) provided the sub-basins parameters which are overlaid with the
real-time simulations to determine which sub-basins are affected by flood risk. The flood animation is
developed for mitigation and quick decision making for safety and evacuation of flood victims in the
Terengganu River catchment. The 3D simulations produce flood risk zones models which illustrate the
affected zones by the flood. The 25 sub-basins parameters have distinct characters which influence
the stream flow, soils, slopes and land cover. That represent areas affected by flood in Kuala
Terengganu. The 25 sub-basins parameters have unique characteristics that influence the river flow,
land cover, soil and slopes. One of the effective ways of flood monitoring is to see it physically
occurring or happening in real-time. The solution is to set the model at the simulation in the 3D
environment. The Terengganu River catchment was successfully delineated and simulated using the
sub-basins to identify zones that are affected by the flood risk. The impacts of flood risk usually take
place during the monsoon period, especially in Peninsular Malaysia. The Terengganu catchment is
liable to flooding during the period of monsoon. The average rainfall during flash flood reaches to
3000mm of rain, with more than 24 hours of a continuous heavy rain shower. The flood event mostly
affects peninsular Malaysia from Decembers to January.