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the area of impervious surface would decrease infiltration of precipitation, thus increase runoff (Dunne and Leopold, 1978; Gordon et al., 1992; Leopold 1994). Impervious surfaces are anthropogenic features through which water cannot infiltrate into the soil such as roads, driveways, sidewalks, parking lots, rooftops and etc. Increased runoff from impervious surface is a major concern in urban areas (Scholz, 2004). These will increase the proportion to the cover of impervious surface in a watershed hence the water discharge and flood magnitudes is increased. Moreover due to the humid tropical watershed in Malaysia, the rainfall in the Malaysia is quite high therefore the volumes of surface runoff and the incidence of flooding and sedimentation of receiving water bodies have been greatly increased. The objectives of this study are: (1) to quantify impervious surface changes; (2) to study the impact of urbanization (impervious surface changes) to urban water cycle. Â Remote Sensing is a data sources for monitoring urban growth and its environmental impact. Remote sensing techniques have been used in this study for quantifying the impervious surface changes by integrating ASTER satellite imagery with in-situ data. The changes area which has occurred in an urbanized watershed can be explicitly quantified using a post-classification comparison approach of impervious surface change detection from remote sensing images. Then, further study on impacts by relating the changes in impervious surface to the responses of the rainfall events using a Geographic Information System (GIS)-based hydrologic model. Â Furthermore, related urbanization data study area analysed which the satellite derived runoff are compared with in-situ stream flow at urbanized watershed in Peninsular Malaysia for ten years period (2000-2010). |