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Floods are a natural calamity that causes loss of human life and destruction of property. They are caused by riverine, coastal and storm surges, cyclones, and tsunami waves. The primary causes of urban floods are an unusual rise in quantum of rainfall, extreme man-made changes in land-use–land-cover patterns, and consequent detrimental hydrological impacts. There are different methods available for flood estimation like rational formulae and empirical methods for approximate estimation of flood peak discharge, but they cannot be applied widely, and their application is confined to a particular region. The current study first discusses the causes of urban floods and then assesses the appropriate flood modeling methods that can be effectively used for urban catchments. Flood modeling methods deployed internationally and nationally in major- and medium-sized cities are discussed, and the research gap is identified. The advantages and demerits of each method are analyzed, and the parameters involved are also identified. An integrated modeling approach is chosen for this case study. In India, only coastal megacities have been considered for flood modeling studies thus far. There have been no research studies conducted on medium-sized urban catchment areas using an integrated modeling approach. Therefore, the present article reviews all the features of a novel integrated flood modeling approach which can be adopted for a medium-sized dendritic pattern ungauged urban catchment area.

The main objective of the present study is to enhance the accessibility facilities for local public to educational centers in Tiruchirappalli City. For this approach, the existing K-12 schools, Census tracts and road network were spatially plotted using the techniques of geospatial system. Spatial accessibility index is computed using Three-step floating catchment area (3SFCA) method. The findings indicate (39%) of catchment area has been shortage of education facilities. The index of 3SFCA and its spatial pattern has been compared, validated using enhanced two-step floating catchment area (E2SFCA) method. The incorporated Gaussian weight of 3SFCA clearly reduces the high estimate of demand problem of the study area. Through 3SFCA and E2SFCA, the number of wards observed to be shortage is 14 and 26 respectively. Overall, the analysis concludes that 3SFCA is an effective method in spatial planning of educational facilities. In future, this study enables the urban planners and decision makers to maximize spatial accessibility by establishing a new facility and improve the existing facilities in shortage region.