ABSTRACT
Increase in urbanization leads to higher impervious areas and correspondingly with high intensity and long duration rainfall leads to larger peaks and reduced time to peak in flood hydrograph, causing severe flooding in the urban areas. Especially, coastal urban areas are more vulnerable to flooding under combined influence of heavy rainfall and high tides. Coastal urban cities in most parts of the world are vulnerable to flooding, which may lead to immense loss of life, property and livelihoods of its inhabitants. Due to the complexity of the problem, an integrated approach of numerical modelling coupled with geo spatial techniques of Remote Sensing (RS) and Geographic Information System (GIS) is required for appropriate flood assessment and remedial measures. In this paper, an integrated approach of flood assessment in coastal urban watershed using numerical models and geo-spatial techniques has been described. Further, the various aspects of urban flooding, modelling and theoretical developments are discussed and the flood assessment of coastal urban watersheds are demonstrated using two case studies with integrated approach of numerical modelling and geo-spatial techniques.
