High resolution terrain height data and landuse information are the two important inputs required to realistically budget floodplain storage and conveyance and the spatial distribution of resistance parameters. Rational formula / SCS curve number can be used to estimate the surface runoff from the urban catchments. Using the DEM generated from Lidar/ground survey, slopes of the study area can calculated. Delineation of suitable subcatchments of basin can be carried out using the DEM. Distribution of the peak flow rates along the drainage network at different nodes can be estimated. The estimated peak runoff rate shall be compared with carrying capacity of storm water drains to judge whether estimated runoff will flood the area or not. The extent of flooding can be estimated using two-dimensional
hydrodynamic modeling.